remove load_dotenv from test file

- Ollama CI: fail the step immediately if model pull fails after 3
  retries instead of silently proceeding to tests
- Azure OpenAI file search: add the same vector-store readiness polling
  that was applied to the non-Azure OpenAI tests, preventing eventual
  consistency race conditions

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.github/scripts/check_team_membership.js

@@ -0,0 +1,61 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+/**
+ * Resolve the issue author and check their team membership.
+ *
+ * @param {object} opts
+ * @param {object} opts.github - Octokit REST client from actions/github-script
+ * @param {object} opts.context - GitHub Actions context
+ * @param {object} opts.core - GitHub Actions core toolkit
+ * @param {string} opts.teamSlug - Team slug to check membership against
+ * @param {string|number} opts.issueNumber - Issue number to resolve author for
+ * @returns {Promise<{author: string|null, isTeamMember: boolean}>}
+ */
+async function checkTeamMembership({ github, context, core, teamSlug, issueNumber }) {
+  let author = context.payload.issue?.user?.login;
+  if (!author) {
+    const { data: issue } = await github.rest.issues.get({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      issue_number: Number(issueNumber),
+    });
+    author = issue.user?.login;
+  }
+
+  if (!author) {
+    core.setFailed('Could not determine issue author (user may be deleted).');
+    return { author: null, isTeamMember: false };
+  }
+
+  try {
+    await github.rest.teams.getByName({
+      org: context.repo.owner,
+      team_slug: teamSlug,
+    });
+  } catch (error) {
+    core.setFailed(`Team lookup failed for ${teamSlug}: ${error.message}`);
+    throw error;
+  }
+
+  let isTeamMember = false;
+  try {
+    const teamMembership = await github.rest.teams.getMembershipForUserInOrg({
+      org: context.repo.owner,
+      team_slug: teamSlug,
+      username: author,
+    });
+    isTeamMember = teamMembership.data.state === 'active';
+  } catch (error) {
+    if (error.status === 404) {
+      core.info(`Author ${author} is not a member of team ${teamSlug}.`);
+      isTeamMember = false;
+    } else {
+      core.setFailed(`Team membership lookup failed for ${author}: ${error.message}`);
+      throw error;
+    }
+  }
+
+  return { author, isTeamMember };
+}
+
+module.exports = checkTeamMembership;

.github/tests/test_check_team_membership.js

@@ -0,0 +1,178 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+/**
+ * Tests for check_team_membership.js.
+ *
+ * Run with: node --test .github/tests/test_check_team_membership.js
+ */
+
+const { describe, it } = require('node:test');
+const assert = require('node:assert/strict');
+
+const checkTeamMembership = require('../scripts/check_team_membership.js');
+
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+function createMocks({ payloadIssue = undefined, apiUser = 'api-user', teamState = 'active' } = {}) {
+  const core = {
+    _infoMessages: [],
+    _failedMessages: [],
+    info(msg) { this._infoMessages.push(msg); },
+    setFailed(msg) { this._failedMessages.push(msg); },
+  };
+
+  const context = {
+    payload: { issue: payloadIssue },
+    repo: { owner: 'test-org', repo: 'test-repo' },
+  };
+
+  const github = {
+    rest: {
+      issues: {
+        get: async () => ({
+          data: { user: apiUser ? { login: apiUser } : null },
+        }),
+      },
+      teams: {
+        getByName: async () => ({}),
+        getMembershipForUserInOrg: async () => ({
+          data: { state: teamState },
+        }),
+      },
+    },
+  };
+
+  return { core, context, github };
+}
+
+const BASE_OPTS = { teamSlug: 'my-team', issueNumber: '123' };
+
+
+// ---------------------------------------------------------------------------
+// Author resolution
+// ---------------------------------------------------------------------------
+
+describe('author resolution', () => {
+  it('resolves author from event payload', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'payload-user' } },
+    });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, 'payload-user');
+  });
+
+  it('resolves author via API when payload issue is absent', async () => {
+    const { github, context, core } = createMocks({ apiUser: 'api-user' });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, 'api-user');
+  });
+
+  it('resolves author via API when payload issue user is null (deleted account)', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: null },
+      apiUser: 'fetched-user',
+    });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, 'fetched-user');
+  });
+
+  it('handles deleted account when API also returns null user', async () => {
+    const { github, context, core } = createMocks({ apiUser: null });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, null);
+    assert.equal(result.isTeamMember, false);
+    assert.ok(core._failedMessages.some(m => m.includes('deleted')));
+  });
+});
+
+
+// ---------------------------------------------------------------------------
+// Team lookup
+// ---------------------------------------------------------------------------
+
+describe('team lookup', () => {
+  it('fails the job when team lookup errors', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'user1' } },
+    });
+    const error = new Error('Bad credentials');
+    github.rest.teams.getByName = async () => { throw error; };
+
+    await assert.rejects(
+      () => checkTeamMembership({ github, context, core, ...BASE_OPTS }),
+      (err) => err === error,
+    );
+    assert.ok(core._failedMessages.some(m => m.includes('Team lookup failed')));
+  });
+});
+
+
+// ---------------------------------------------------------------------------
+// Team membership
+// ---------------------------------------------------------------------------
+
+describe('team membership', () => {
+  it('returns true for active team member', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'member' } },
+      teamState: 'active',
+    });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.isTeamMember, true);
+  });
+
+  it('returns false for pending team member', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'pending-user' } },
+      teamState: 'pending',
+    });
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.isTeamMember, false);
+  });
+
+  it('treats 404 membership response as non-member without failing', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'outsider' } },
+    });
+    const notFoundError = new Error('Not Found');
+    notFoundError.status = 404;
+    github.rest.teams.getMembershipForUserInOrg = async () => { throw notFoundError; };
+
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.isTeamMember, false);
+    assert.equal(core._failedMessages.length, 0);
+    assert.ok(core._infoMessages.some(m => m.includes('not a member')));
+  });
+
+  it('fails the job on non-404 membership errors', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'user1' } },
+    });
+    const serverError = new Error('Internal Server Error');
+    serverError.status = 500;
+    github.rest.teams.getMembershipForUserInOrg = async () => { throw serverError; };
+
+    await assert.rejects(
+      () => checkTeamMembership({ github, context, core, ...BASE_OPTS }),
+      (err) => err === serverError,
+    );
+    assert.ok(core._failedMessages.some(m => m.includes('membership lookup failed')));
+  });
+
+  it('fails the job on membership errors without status code', async () => {
+    const { github, context, core } = createMocks({
+      payloadIssue: { user: { login: 'user1' } },
+    });
+    const networkError = new Error('ECONNREFUSED');
+    github.rest.teams.getMembershipForUserInOrg = async () => { throw networkError; };
+
+    await assert.rejects(
+      () => checkTeamMembership({ github, context, core, ...BASE_OPTS }),
+      (err) => err === networkError,
+    );
+    assert.ok(core._failedMessages.some(m => m.includes('membership lookup failed')));
+  });
+});

.github/workflows/issue-triage.yml

@@ -0,0 +1,199 @@
+name: Issue Triage
+
+on:
+  workflow_dispatch:
+    inputs:
+      issue_number:
+        description: Issue number to triage
+        required: true
+        type: string
+
+permissions:
+  contents: read
+  issues: write
+  id-token: write
+
+concurrency:
+  group: issue-triage-${{ github.repository }}-${{ github.event.issue.number || inputs.issue_number || github.run_id }}
+  cancel-in-progress: true
+
+env:
+  DEVFLOW_REPOSITORY: ${{ vars.DF_REPO }}
+  DEVFLOW_REF: main
+  TARGET_REPO_PATH: ${{ github.workspace }}/target-repo
+  DEVFLOW_PATH: ${{ github.workspace }}/devflow
+
+jobs:
+  team_check:
+    runs-on: ubuntu-latest
+    outputs:
+      is_team_member: ${{ steps.check.outputs.is_team_member }}
+      issue_number: ${{ steps.issue.outputs.issue_number }}
+      repo: ${{ steps.issue.outputs.repo }}
+    steps:
+      - name: Resolve issue metadata
+        id: issue
+        shell: bash
+        env:
+          ISSUE_NUMBER_EVENT: ${{ github.event.issue.number }}
+          ISSUE_NUMBER_INPUT: ${{ inputs.issue_number }}
+        run: |
+          set -euo pipefail
+
+          if [[ "${GITHUB_EVENT_NAME}" == "issues" ]]; then
+            issue_number="${ISSUE_NUMBER_EVENT}"
+          else
+            issue_number="${ISSUE_NUMBER_INPUT}"
+          fi
+
+          if [[ ! "$issue_number" =~ ^[1-9][0-9]*$ ]]; then
+            echo "Could not determine issue number; for workflow_dispatch runs, the 'issue_number' input is required." >&2
+            exit 1
+          fi
+
+          echo "issue_number=${issue_number}" >> "$GITHUB_OUTPUT"
+          echo "repo=${GITHUB_REPOSITORY}" >> "$GITHUB_OUTPUT"
+
+      - name: Checkout scripts
+        uses: actions/checkout@v6
+        with:
+          sparse-checkout: .github/scripts
+          fetch-depth: 1
+          persist-credentials: false
+
+      - name: Check issue author team membership
+        id: check
+        uses: actions/github-script@v8
+        env:
+          TEAM_NAME: ${{ secrets.DEVELOPER_TEAM }}
+          ISSUE_NUMBER: ${{ steps.issue.outputs.issue_number }}
+        with:
+          github-token: ${{ secrets.GH_ACTIONS_PR_WRITE }}
+          script: |
+            const checkTeamMembership = require('./.github/scripts/check_team_membership.js');
+            const { author, isTeamMember } = await checkTeamMembership({
+              github,
+              context,
+              core,
+              teamSlug: process.env.TEAM_NAME,
+              issueNumber: process.env.ISSUE_NUMBER,
+            });
+            core.setOutput('is_team_member', isTeamMember ? 'true' : 'false');
+            if (isTeamMember) {
+              core.info(`Author ${author} is a team member; skipping auto-triage.`);
+            } else {
+              core.info(`Author ${author} is not a team member; proceeding with triage.`);
+            }
+
+  triage:
+    runs-on: ubuntu-latest
+    needs: team_check
+    if: ${{ needs.team_check.outputs.is_team_member == 'false' }}
+    environment: integration
+    timeout-minutes: 60
+
+    steps:
+      # Safe checkout: base repo only.
+      - name: Checkout target repo base
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+          persist-credentials: false
+          path: target-repo
+
+      # Private DevFlow (maf-dashboard) checkout.
+      - name: Checkout DevFlow
+        uses: actions/checkout@v6
+        with:
+          repository: ${{ env.DEVFLOW_REPOSITORY }}
+          ref: ${{ env.DEVFLOW_REF }}
+          token: ${{ secrets.DEVFLOW_TOKEN }}
+          fetch-depth: 1
+          persist-credentials: false
+          path: devflow
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.13"
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v7
+        with:
+          version: "0.11.x"
+          enable-cache: true
+
+      - name: Install DevFlow dependencies
+        working-directory: ${{ env.DEVFLOW_PATH }}
+        run: uv sync --frozen
+
+      - name: Azure CLI Login
+        uses: azure/login@v2
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+
+      - name: Classify issue relevance
+        id: spam
+        working-directory: ${{ env.DEVFLOW_PATH }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          SK_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
+          AGENT_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
+          ISSUE_REPO: ${{ needs.team_check.outputs.repo }}
+          ISSUE_NUMBER: ${{ needs.team_check.outputs.issue_number }}
+        run: |
+          uv run python scripts/classify_issue_spam.py \
+            --repo "$ISSUE_REPO" \
+            --issue-number "$ISSUE_NUMBER" \
+            --repo-path "${TARGET_REPO_PATH}" \
+            --apply-labels
+
+      - name: Stop after spam gate
+        if: ${{ steps.spam.outputs.decision != 'allow' }}
+        shell: bash
+        env:
+          SPAM_DECISION: ${{ steps.spam.outputs.decision }}
+        run: |
+          echo "Stopping: spam gate decided: ${SPAM_DECISION}"
+          exit 1
+
+      - name: Reproduce reported issue
+        if: ${{ steps.spam.outputs.decision == 'allow' }}
+        id: repro
+        working-directory: ${{ env.DEVFLOW_PATH }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GH_COPILOT_TOKEN: ${{ secrets.GH_COPILOT_TOKEN }}
+          SK_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
+          AGENT_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
+          ISSUE_REPO: ${{ needs.team_check.outputs.repo }}
+          ISSUE_NUMBER: ${{ needs.team_check.outputs.issue_number }}
+          # Model-provider settings for generated repro code. Never enter the
+          # agent prompt; consumed by SDK constructors via os.environ. Azure
+          # OpenAI and Foundry auth via AAD from the azure/login step above.
+          OPENAI_API_KEY: ${{ secrets.OPENAI__APIKEY }}
+          OPENAI_CHAT_COMPLETION_MODEL: ${{ vars.OPENAI__CHATMODELID }}
+          OPENAI_CHAT_MODEL: ${{ vars.OPENAI__RESPONSESMODELID }}
+          OPENAI_MODEL: ${{ vars.OPENAI__RESPONSESMODELID }}
+          OPENAI_EMBEDDING_MODEL: ${{ vars.OPENAI_EMBEDDING_MODEL_ID }}
+          AZURE_OPENAI_ENDPOINT: ${{ vars.AZUREOPENAI__ENDPOINT }}
+          AZURE_OPENAI_CHAT_COMPLETION_MODEL: ${{ vars.AZUREOPENAI__CHATDEPLOYMENTNAME }}
+          AZURE_OPENAI_CHAT_MODEL: ${{ vars.AZUREOPENAI__RESPONSESDEPLOYMENTNAME }}
+          AZURE_OPENAI_MODEL: ${{ vars.AZUREOPENAI__RESPONSESDEPLOYMENTNAME }}
+          AZURE_OPENAI_EMBEDDING_MODEL: ${{ vars.AZURE_OPENAI_EMBEDDING_DEPLOYMENT_NAME }}
+          FOUNDRY_PROJECT_ENDPOINT: ${{ vars.FOUNDRY_PROJECT_ENDPOINT }}
+          FOUNDRY_MODEL: ${{ vars.FOUNDRY_MODEL }}
+          FOUNDRY_AGENT_NAME: ${{ vars.FOUNDRY_AGENT_NAME }}
+          FOUNDRY_AGENT_VERSION: ${{ vars.FOUNDRY_AGENT_VERSION }}
+          FOUNDRY_MODELS_ENDPOINT: ${{ vars.FOUNDRY_MODELS_ENDPOINT || '' }}
+          FOUNDRY_MODELS_API_KEY: ${{ secrets.FOUNDRY_MODELS_API_KEY || '' }}
+          FOUNDRY_EMBEDDING_MODEL: ${{ vars.FOUNDRY_EMBEDDING_MODEL || '' }}
+          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
+          ANTHROPIC_CHAT_MODEL: ${{ vars.ANTHROPIC_CHAT_MODEL_ID }}
+        run: |
+          uv run python scripts/trigger_issue_repro.py \
+            --repo "$ISSUE_REPO" \
+            --issue-number "$ISSUE_NUMBER" \
+            --github-username "$GITHUB_ACTOR"

.github/workflows/python-integration-tests.yml

@@ -157,6 +157,8 @@ jobs:
       ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
       ANTHROPIC_CHAT_MODEL: ${{ vars.ANTHROPIC_CHAT_MODEL_ID }}
       LOCAL_MCP_URL: ${{ vars.LOCAL_MCP__URL }}
+      OLLAMA_MODEL: qwen2.5:1.5b
+      OLLAMA_EMBEDDING_MODEL: nomic-embed-text
     defaults:
       run:
         working-directory: python
@@ -171,6 +173,43 @@ jobs:
         with:
           python-version: ${{ env.UV_PYTHON }}
           os: ${{ runner.os }}
+      - name: Install Ollama
+        run: curl -fsSL https://ollama.com/install.sh | sh
+        working-directory: .
+      - name: Cache Ollama models
+        uses: actions/cache@v4
+        with:
+          path: ~/.ollama/models
+          key: ollama-models-qwen2.5-1.5b-nomic-embed-text-v1
+      - name: Start Ollama and pull models
+        run: |
+          # Stop any Ollama instance auto-started by the install script
+          pkill ollama || true
+          sleep 2
+          ollama serve &
+          for i in $(seq 1 30); do
+            if curl -sf http://localhost:11434/api/tags > /dev/null 2>&1; then
+              break
+            fi
+            sleep 1
+          done
+          # Pull models with retry for transient 429 rate limits
+          for model in qwen2.5:1.5b nomic-embed-text; do
+            pulled=false
+            for attempt in 1 2 3; do
+              if ollama pull "$model"; then
+                pulled=true
+                break
+              fi
+              echo "Retry $attempt for $model (waiting 15s)..."
+              sleep 15
+            done
+            if [ "$pulled" != "true" ]; then
+              echo "ERROR: Failed to pull $model after 3 attempts"
+              exit 1
+            fi
+          done
+        working-directory: .
       - name: Start local MCP server
         id: local-mcp
         uses: ./.github/actions/setup-local-mcp-server
@@ -271,7 +310,7 @@ jobs:
           -m integration
           -n logical --dist worksteal
           -x
-          --timeout=360 --session-timeout=900 --timeout_method thread
+          --timeout=480 --session-timeout=900 --timeout_method thread
           --retries 2 --retry-delay 5
           --junitxml=pytest.xml
       - name: Upload test results
@@ -336,6 +375,53 @@ jobs:
           path: ./python/pytest.xml
           if-no-files-found: ignore
 
+  # Foundry Hosting integration tests
+  python-tests-foundry-hosting:
+    name: Python Integration Tests - Foundry Hosting
+    runs-on: ubuntu-latest
+    environment: integration
+    timeout-minutes: 60
+    env:
+      FOUNDRY_PROJECT_ENDPOINT: ${{ vars.FOUNDRY_PROJECT_ENDPOINT }}
+      FOUNDRY_MODEL: ${{ vars.FOUNDRY_MODEL }}
+    defaults:
+      run:
+        working-directory: python
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          ref: ${{ inputs.checkout-ref }}
+          persist-credentials: false
+      - name: Set up python and install the project
+        id: python-setup
+        uses: ./.github/actions/python-setup
+        with:
+          python-version: ${{ env.UV_PYTHON }}
+          os: ${{ runner.os }}
+      - name: Azure CLI Login
+        uses: azure/login@v2
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+      - name: Test with pytest (Foundry Hosting integration)
+        timeout-minutes: 15
+        run: >
+          uv run pytest --import-mode=importlib
+          packages/foundry_hosting/tests
+          -m integration
+          -n logical --dist worksteal
+          --timeout=120 --session-timeout=900 --timeout_method thread
+          --retries 2 --retry-delay 5
+          --junitxml=pytest.xml
+      - name: Upload test results
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: test-results-foundry-hosting
+          path: ./python/pytest.xml
+          if-no-files-found: ignore
+
   # Azure Cosmos integration tests
   python-tests-cosmos:
     name: Python Integration Tests - Cosmos
@@ -388,9 +474,9 @@ jobs:
           path: ./python/pytest.xml
           if-no-files-found: ignore
 
-  # Flaky test trend report (aggregates per-job JUnit XML results)
-  python-flaky-test-report:
-    name: Flaky Test Report
+  # Integration test trend report (aggregates per-job JUnit XML results)
+  python-integration-test-report:
+    name: Integration Test Report
     if: >
       always() &&
       (contains(join(needs.*.result, ','), 'success') ||
@@ -402,6 +488,7 @@ jobs:
         python-tests-misc-integration,
         python-tests-functions,
         python-tests-foundry,
+        python-tests-foundry-hosting,
         python-tests-cosmos,
       ]
     runs-on: ubuntu-latest
@@ -423,36 +510,36 @@ jobs:
         with:
           pattern: test-results-*
           path: test-results/
-      - name: Restore flaky report history cache
+      - name: Restore report history cache
         uses: actions/cache/restore@v4
         with:
-          path: python/flaky-report-history.json
-          key: flaky-report-history-integration-${{ github.run_id }}
+          path: python/integration-report-history.json
+          key: integration-report-history-integration-${{ github.run_id }}
           restore-keys: |
-            flaky-report-history-integration-
+            integration-report-history-integration-
       - name: Generate trend report
         run: >
-          uv run python scripts/flaky_report/aggregate.py
+          uv run python scripts/integration_test_report/aggregate.py
           ../test-results/
-          flaky-report-history.json
-          flaky-test-report.md
+          integration-report-history.json
+          integration-test-report.md
       - name: Post to Job Summary
         if: always()
-        run: cat flaky-test-report.md >> $GITHUB_STEP_SUMMARY
-      - name: Save flaky report history cache
+        run: cat integration-test-report.md >> $GITHUB_STEP_SUMMARY
+      - name: Save report history cache
         if: always()
         uses: actions/cache/save@v4
         with:
-          path: python/flaky-report-history.json
-          key: flaky-report-history-integration-${{ github.run_id }}
+          path: python/integration-report-history.json
+          key: integration-report-history-integration-${{ github.run_id }}
       - name: Upload unified trend report
         if: always()
         uses: actions/upload-artifact@v7
         with:
-          name: flaky-test-report
+          name: integration-test-report
           path: |
-            python/flaky-test-report.md
-            python/flaky-report-history.json
+            python/integration-test-report.md
+            python/integration-report-history.json
 
   python-integration-tests-check:
     if: always()
@@ -465,6 +552,7 @@ jobs:
         python-tests-misc-integration,
         python-tests-functions,
         python-tests-foundry,
+        python-tests-foundry-hosting,
         python-tests-cosmos
       ]
     steps:

.github/workflows/python-merge-tests.yml

@@ -38,6 +38,7 @@ jobs:
       miscChanged: ${{ steps.filter.outputs.misc }}
       functionsChanged: ${{ steps.filter.outputs.functions }}
       foundryChanged: ${{ steps.filter.outputs.foundry }}
+      foundryHostingChanged: ${{ steps.filter.outputs.foundry_hosting }}
       cosmosChanged: ${{ steps.filter.outputs.cosmos }}
     steps:
       - uses: actions/checkout@v6
@@ -80,6 +81,8 @@ jobs:
               - 'python/packages/foundry/**'
               - 'python/samples/**/providers/foundry/**'
               - 'python/samples/02-agents/embeddings/foundry_embeddings.py'
+            foundry_hosting:
+              - 'python/packages/foundry_hosting/**'
             cosmos:
               - 'python/packages/azure-cosmos/**'
       # run only if 'python' files were changed
@@ -275,6 +278,8 @@ jobs:
       ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
       ANTHROPIC_CHAT_MODEL: ${{ vars.ANTHROPIC_CHAT_MODEL_ID }}
       LOCAL_MCP_URL: ${{ vars.LOCAL_MCP__URL }}
+      OLLAMA_MODEL: qwen2.5:1.5b
+      OLLAMA_EMBEDDING_MODEL: nomic-embed-text
     defaults:
       run:
         working-directory: python
@@ -286,6 +291,43 @@ jobs:
         with:
           python-version: ${{ env.UV_PYTHON }}
           os: ${{ runner.os }}
+      - name: Install Ollama
+        run: curl -fsSL https://ollama.com/install.sh | sh
+        working-directory: .
+      - name: Cache Ollama models
+        uses: actions/cache@v4
+        with:
+          path: ~/.ollama/models
+          key: ollama-models-qwen2.5-1.5b-nomic-embed-text-v1
+      - name: Start Ollama and pull models
+        run: |
+          # Stop any Ollama instance auto-started by the install script
+          pkill ollama || true
+          sleep 2
+          ollama serve &
+          for i in $(seq 1 30); do
+            if curl -sf http://localhost:11434/api/tags > /dev/null 2>&1; then
+              break
+            fi
+            sleep 1
+          done
+          # Pull models with retry for transient 429 rate limits
+          for model in qwen2.5:1.5b nomic-embed-text; do
+            pulled=false
+            for attempt in 1 2 3; do
+              if ollama pull "$model"; then
+                pulled=true
+                break
+              fi
+              echo "Retry $attempt for $model (waiting 15s)..."
+              sleep 15
+            done
+            if [ "$pulled" != "true" ]; then
+              echo "ERROR: Failed to pull $model after 3 attempts"
+              exit 1
+            fi
+          done
+        working-directory: .
       - name: Start local MCP server
         id: local-mcp
         uses: ./.github/actions/setup-local-mcp-server
@@ -400,7 +442,7 @@ jobs:
           -m integration
           -n logical --dist worksteal
           -x
-          --timeout=360 --session-timeout=900 --timeout_method thread
+          --timeout=480 --session-timeout=900 --timeout_method thread
           --retries 2 --retry-delay 5
           --junitxml=pytest.xml
         working-directory: ./python
@@ -488,6 +530,67 @@ jobs:
           path: ./python/pytest.xml
           if-no-files-found: ignore
 
+  # Foundry Hosting integration tests
+  python-tests-foundry-hosting:
+    name: Python Tests - Foundry Hosting Integration
+    needs: paths-filter
+    if: >
+      github.event_name != 'pull_request' &&
+      needs.paths-filter.outputs.pythonChanges == 'true' &&
+      (github.event_name != 'merge_group' ||
+       needs.paths-filter.outputs.foundryHostingChanged == 'true' ||
+       needs.paths-filter.outputs.coreChanged == 'true')
+    runs-on: ubuntu-latest
+    environment: integration
+    env:
+      FOUNDRY_PROJECT_ENDPOINT: ${{ vars.FOUNDRY_PROJECT_ENDPOINT }}
+      FOUNDRY_MODEL: ${{ vars.FOUNDRY_MODEL }}
+    defaults:
+      run:
+        working-directory: python
+    steps:
+      - uses: actions/checkout@v6
+      - name: Set up python and install the project
+        id: python-setup
+        uses: ./.github/actions/python-setup
+        with:
+          python-version: ${{ env.UV_PYTHON }}
+          os: ${{ runner.os }}
+      - name: Azure CLI Login
+        if: github.event_name != 'pull_request'
+        uses: azure/login@v2
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+      - name: Test with pytest (Foundry Hosting integration)
+        timeout-minutes: 15
+        run: >
+          uv run pytest --import-mode=importlib
+          packages/foundry_hosting/tests
+          -m integration
+          -n logical --dist worksteal
+          --timeout=120 --session-timeout=900 --timeout_method thread
+          --retries 2 --retry-delay 5
+          --junitxml=pytest.xml
+        working-directory: ./python
+      - name: Surface failing tests
+        if: always()
+        uses: pmeier/pytest-results-action@v0.7.2
+        with:
+          path: ./python/pytest.xml
+          summary: true
+          display-options: fEX
+          fail-on-empty: false
+          title: Foundry Hosting integration test results
+      - name: Upload test results
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: test-results-foundry-hosting
+          path: ./python/pytest.xml
+          if-no-files-found: ignore
+
   # TODO: Add python-tests-lab
 
   # Azure Cosmos integration tests
@@ -555,9 +658,9 @@ jobs:
           path: ./python/pytest.xml
           if-no-files-found: ignore
 
-  # Flaky test trend report (aggregates per-job JUnit XML results)
-  python-flaky-test-report:
-    name: Flaky Test Report
+  # Integration test trend report (aggregates per-job JUnit XML results)
+  python-integration-test-report:
+    name: Integration Test Report
     if: >
       always() &&
       (contains(join(needs.*.result, ','), 'success') ||
@@ -569,6 +672,7 @@ jobs:
         python-tests-misc-integration,
         python-tests-functions,
         python-tests-foundry,
+        python-tests-foundry-hosting,
         python-tests-cosmos,
       ]
     runs-on: ubuntu-latest
@@ -587,36 +691,36 @@ jobs:
         with:
           pattern: test-results-*
           path: test-results/
-      - name: Restore flaky report history cache
+      - name: Restore report history cache
         uses: actions/cache/restore@v4
         with:
-          path: python/flaky-report-history.json
-          key: flaky-report-history-merge-${{ github.run_id }}
+          path: python/integration-report-history.json
+          key: integration-report-history-merge-${{ github.run_id }}
           restore-keys: |
-            flaky-report-history-merge-
+            integration-report-history-merge-
       - name: Generate trend report
         run: >
-          uv run python scripts/flaky_report/aggregate.py
+          uv run python scripts/integration_test_report/aggregate.py
           ../test-results/
-          flaky-report-history.json
-          flaky-test-report.md
+          integration-report-history.json
+          integration-test-report.md
       - name: Post to Job Summary
         if: always()
-        run: cat flaky-test-report.md >> $GITHUB_STEP_SUMMARY
-      - name: Save flaky report history cache
+        run: cat integration-test-report.md >> $GITHUB_STEP_SUMMARY
+      - name: Save report history cache
         if: always()
         uses: actions/cache/save@v4
         with:
-          path: python/flaky-report-history.json
-          key: flaky-report-history-merge-${{ github.run_id }}
+          path: python/integration-report-history.json
+          key: integration-report-history-merge-${{ github.run_id }}
       - name: Upload unified trend report
         if: always()
         uses: actions/upload-artifact@v7
         with:
-          name: flaky-test-report
+          name: integration-test-report
           path: |
-            python/flaky-test-report.md
-            python/flaky-report-history.json
+            python/integration-test-report.md
+            python/integration-report-history.json
 
   python-integration-tests-check:
     if: always()
@@ -629,6 +733,7 @@ jobs:
         python-tests-misc-integration,
         python-tests-functions,
         python-tests-foundry,
+        python-tests-foundry-hosting,
         python-tests-cosmos,
       ]
     steps:

.gitignore

@@ -242,3 +242,7 @@ python/dotnet-ref
 # Generated filtered solution files (created by eng/scripts/New-FilteredSolution.ps1)
 dotnet/filtered-*.slnx
 **/*.lscache
+
+# Local tool state
+.omc/
+.omx/

dotnet/Directory.Packages.props

@@ -22,9 +22,9 @@
     <PackageVersion Include="Aspire.Microsoft.Azure.Cosmos" Version="$(AspireAppHostSdkVersion)" />
     <PackageVersion Include="CommunityToolkit.Aspire.OllamaSharp" Version="13.0.0" />
     <!-- Azure.* -->
-    <PackageVersion Include="Azure.AI.AgentServer.Core" Version="1.0.0-beta.22" />
-    <PackageVersion Include="Azure.AI.AgentServer.Invocations" Version="1.0.0-beta.1" />
-    <PackageVersion Include="Azure.AI.AgentServer.Responses" Version="1.0.0-beta.3" />
+    <PackageVersion Include="Azure.AI.AgentServer.Core" Version="1.0.0-beta.23" />
+    <PackageVersion Include="Azure.AI.AgentServer.Invocations" Version="1.0.0-beta.3" />
+    <PackageVersion Include="Azure.AI.AgentServer.Responses" Version="1.0.0-beta.4" />
     <PackageVersion Include="Azure.AI.Projects" Version="2.0.0" />
     <PackageVersion Include="Azure.AI.Agents.Persistent" Version="1.2.0-beta.10" />
     <PackageVersion Include="Azure.AI.OpenAI" Version="2.9.0-beta.1" />
@@ -56,15 +56,15 @@
     <PackageVersion Include="System.Threading.Tasks.Extensions" Version="4.6.3" />
     <PackageVersion Include="System.Net.Security" Version="4.3.2" />
     <!-- OpenTelemetry -->
-    <PackageVersion Include="OpenTelemetry" Version="1.15.0" />
-    <PackageVersion Include="OpenTelemetry.Api" Version="1.15.0" />
-    <PackageVersion Include="OpenTelemetry.Exporter.Console" Version="1.15.0" />
-    <PackageVersion Include="OpenTelemetry.Exporter.InMemory" Version="1.15.0" />
-    <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.0" />
-    <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.14.0" />
-    <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.14.0" />
-    <PackageVersion Include="OpenTelemetry.Instrumentation.Http" Version="1.14.0" />
-    <PackageVersion Include="OpenTelemetry.Instrumentation.Runtime" Version="1.14.0" />
+    <PackageVersion Include="OpenTelemetry" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Api" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Exporter.Console" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Exporter.InMemory" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.15.3" />
+    <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.15.2" />
+    <PackageVersion Include="OpenTelemetry.Instrumentation.Http" Version="1.15.1" />
+    <PackageVersion Include="OpenTelemetry.Instrumentation.Runtime" Version="1.15.1" />
     <!-- Microsoft.AspNetCore.* -->
     <PackageVersion Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="10.0.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Authentication.OpenIdConnect" Version="10.0.0" />
@@ -188,4 +188,4 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
   </ItemGroup>
-</Project>
+</Project>

dotnet/agent-framework-dotnet.slnx

@@ -4,9 +4,6 @@
     <BuildType Name="Publish" />
     <BuildType Name="Release" />
   </Configurations>
-  <Folder Name="/src/Aspire.Hosting.AgentFramework.DevUI/">
-    <Project Path="src/Aspire.Hosting.AgentFramework.DevUI/Aspire.Hosting.AgentFramework.DevUI.csproj" />
-  </Folder>
   <Folder Name="/Samples/">
     <File Path="samples/AGENTS.md" />
     <File Path="samples/README.md" />
@@ -67,6 +64,7 @@
     <Project Path="samples/02-agents/Agents/Agent_Step17_AdditionalAIContext/Agent_Step17_AdditionalAIContext.csproj" />
     <Project Path="samples/02-agents/Agents/Agent_Step18_CompactionPipeline/Agent_Step18_CompactionPipeline.csproj" />
     <Project Path="samples/02-agents/Agents/Agent_Step19_InFunctionLoopCheckpointing/Agent_Step19_InFunctionLoopCheckpointing.csproj" />
+    <Project Path="samples/02-agents/Agents/Agent_Step20_DynamicFunctionTools/Agent_Step20_DynamicFunctionTools.csproj" />
   </Folder>
   <Folder Name="/Samples/02-agents/DeclarativeAgents/">
     <Project Path="samples/02-agents/DeclarativeAgents/ChatClient/DeclarativeChatClientAgents.csproj" />
@@ -162,12 +160,13 @@
     <Project Path="samples/02-agents/AgentsWithFoundry/Agent_Step22_MemorySearch/Agent_Step22_MemorySearch.csproj" />
     <Project Path="samples/02-agents/AgentsWithFoundry/Agent_Step23_LocalMCP/Agent_Step23_LocalMCP.csproj" />
     <Project Path="samples/02-agents/AgentsWithFoundry/Agent_Step24_CodeInterpreterFileDownload/Agent_Step24_CodeInterpreterFileDownload.csproj" />
+    <Project Path="samples/02-agents/AgentsWithFoundry/Agent_Step25_ToolboxServerSideTools/Agent_Step25_ToolboxServerSideTools.csproj" />
   </Folder>
   <Folder Name="/Samples/02-agents/Evaluation/">
-    <Project Path="samples/02-agents/Evaluation/Evaluation_SimpleEval/Evaluation_SimpleEval.csproj" />
     <Project Path="samples/02-agents/Evaluation/Evaluation_CustomEvals/Evaluation_CustomEvals.csproj" />
     <Project Path="samples/02-agents/Evaluation/Evaluation_ExpectedOutputs/Evaluation_ExpectedOutputs.csproj" />
     <Project Path="samples/02-agents/Evaluation/Evaluation_Multimodal/Evaluation_Multimodal.csproj" />
+    <Project Path="samples/02-agents/Evaluation/Evaluation_SimpleEval/Evaluation_SimpleEval.csproj" />
   </Folder>
   <Folder Name="/Samples/02-agents/AgentWithMemory/">
     <File Path="samples/02-agents/AgentWithMemory/README.md" />
@@ -227,6 +226,7 @@
     <Project Path="samples/03-workflows/Declarative/HostedWorkflow/HostedWorkflow.csproj" />
     <Project Path="samples/03-workflows/Declarative/InputArguments/InputArguments.csproj" />
     <Project Path="samples/03-workflows/Declarative/InvokeFunctionTool/InvokeFunctionTool.csproj" />
+    <Project Path="samples/03-workflows/Declarative/InvokeHttpRequest/InvokeHttpRequest.csproj" />
     <Project Path="samples/03-workflows/Declarative/InvokeMcpTool/InvokeMcpTool.csproj" />
     <Project Path="samples/03-workflows/Declarative/Marketing/Marketing.csproj" />
     <Project Path="samples/03-workflows/Declarative/StudentTeacher/StudentTeacher.csproj" />
@@ -348,17 +348,17 @@
     <File Path="samples/02-agents/A2A/README.md" />
     <Project Path="samples/02-agents/A2A/A2AAgent_AsFunctionTools/A2AAgent_AsFunctionTools.csproj" />
     <Project Path="samples/02-agents/A2A/A2AAgent_PollingForTaskCompletion/A2AAgent_PollingForTaskCompletion.csproj" />
-    <Project Path="samples/02-agents/A2A/A2AAgent_StreamReconnection/A2AAgent_StreamReconnection.csproj" />
     <Project Path="samples/02-agents/A2A/A2AAgent_ProtocolSelection/A2AAgent_ProtocolSelection.csproj" />
+    <Project Path="samples/02-agents/A2A/A2AAgent_StreamReconnection/A2AAgent_StreamReconnection.csproj" />
   </Folder>  
   <Folder Name="/Samples/05-end-to-end/">
     <Project Path="samples/05-end-to-end/AgentWithPurview/AgentWithPurview.csproj" />
     <Project Path="samples/05-end-to-end/M365Agent/M365Agent.csproj" />
   </Folder>
   <Folder Name="/Samples/05-end-to-end/Evaluation/">
+    <Project Path="samples/05-end-to-end/Evaluation/Evaluation_ConversationSplits/Evaluation_ConversationSplits.csproj" />
     <Project Path="samples/05-end-to-end/Evaluation/Evaluation_FoundryQuality/Evaluation_FoundryQuality.csproj" />
     <Project Path="samples/05-end-to-end/Evaluation/Evaluation_MixedProviders/Evaluation_MixedProviders.csproj" />
-    <Project Path="samples/05-end-to-end/Evaluation/Evaluation_ConversationSplits/Evaluation_ConversationSplits.csproj" />
   </Folder>
   <Folder Name="/Samples/05-end-to-end/A2AClientServer/">
     <File Path="samples/05-end-to-end/A2AClientServer/README.md" />
@@ -533,6 +533,7 @@
     <File Path="tests/Directory.Build.props" />
   </Folder>
   <Folder Name="/src/">
+    <Project Path="src/Aspire.Hosting.AgentFramework.DevUI/Aspire.Hosting.AgentFramework.DevUI.csproj" />
     <Project Path="src/Microsoft.Agents.AI.A2A/Microsoft.Agents.AI.A2A.csproj" />
     <Project Path="src/Microsoft.Agents.AI.Abstractions/Microsoft.Agents.AI.Abstractions.csproj" />
     <Project Path="src/Microsoft.Agents.AI.AGUI/Microsoft.Agents.AI.AGUI.csproj" />
@@ -543,8 +544,8 @@
     <Project Path="src/Microsoft.Agents.AI.Declarative/Microsoft.Agents.AI.Declarative.csproj" />
     <Project Path="src/Microsoft.Agents.AI.DevUI/Microsoft.Agents.AI.DevUI.csproj" />
     <Project Path="src/Microsoft.Agents.AI.DurableTask/Microsoft.Agents.AI.DurableTask.csproj" />
-    <Project Path="src/Microsoft.Agents.AI.Foundry/Microsoft.Agents.AI.Foundry.csproj" />
     <Project Path="src/Microsoft.Agents.AI.Foundry.Hosting/Microsoft.Agents.AI.Foundry.Hosting.csproj" />
+    <Project Path="src/Microsoft.Agents.AI.Foundry/Microsoft.Agents.AI.Foundry.csproj" />
     <Project Path="src/Microsoft.Agents.AI.GitHub.Copilot/Microsoft.Agents.AI.GitHub.Copilot.csproj" />
     <Project Path="src/Microsoft.Agents.AI.Hosting.A2A.AspNetCore/Microsoft.Agents.AI.Hosting.A2A.AspNetCore.csproj" />
     <Project Path="src/Microsoft.Agents.AI.Hosting.A2A/Microsoft.Agents.AI.Hosting.A2A.csproj" />

dotnet/nuget/nuget-package.props

@@ -1,14 +1,14 @@
 <Project>
   <PropertyGroup>
     <!-- Central version prefix - applies to all nuget packages. -->
-    <VersionPrefix>1.2.0</VersionPrefix>
+    <VersionPrefix>1.3.0</VersionPrefix>
     <RCNumber>1</RCNumber>
-    <DateSuffix>260421</DateSuffix>
+    <DateSuffix>260423</DateSuffix>
     <PackageVersion Condition="'$(IsReleaseCandidate)' == 'true'">$(VersionPrefix)-rc$(RCNumber)</PackageVersion>
     <PackageVersion Condition="'$(IsReleaseCandidate)' != 'true' AND '$(VersionSuffix)' != ''">$(VersionPrefix)-$(VersionSuffix).$(DateSuffix).1</PackageVersion>
     <PackageVersion Condition="'$(IsReleaseCandidate)' != 'true' AND '$(VersionSuffix)' == ''">$(VersionPrefix)-preview.$(DateSuffix).1</PackageVersion>
     <PackageVersion Condition="'$(IsReleased)' == 'true'">$(VersionPrefix)</PackageVersion>
-    <GitTag>1.2.0</GitTag>
+    <GitTag>1.3.0</GitTag>
 
     <Configurations>Debug;Release;Publish</Configurations>
     <IsPackable>true</IsPackable>

dotnet/samples/02-agents/AgentSkills/SubprocessScriptRunner.cs

@@ -5,16 +5,16 @@
 // This is provided for demonstration purposes only.
 
 using System.Diagnostics;
+using System.Text.Json;
 using Microsoft.Agents.AI;
-using Microsoft.Extensions.AI;
 
 /// <summary>
 /// Executes file-based skill scripts as local subprocesses.
 /// </summary>
 /// <remarks>
-/// This runner uses the script's absolute path, converts the arguments
-/// to CLI flags, and returns captured output. It is intended for
-/// demonstration purposes only.
+/// This runner uses the script's absolute path and converts the arguments
+/// to CLI arguments. When the LLM sends a JSON array, each element is used
+/// as a positional argument. It is intended for demonstration purposes only.
 /// </remarks>
 internal static class SubprocessScriptRunner
 {
@@ -24,7 +24,8 @@ internal static class SubprocessScriptRunner
     public static async Task<object?> RunAsync(
         AgentFileSkill skill,
         AgentFileSkillScript script,
-        AIFunctionArguments arguments,
+        JsonElement? arguments,
+        IServiceProvider? serviceProvider,
         CancellationToken cancellationToken)
     {
         if (!File.Exists(script.FullPath))
@@ -61,24 +62,27 @@ internal static class SubprocessScriptRunner
             startInfo.FileName = script.FullPath;
         }
 
-        if (arguments is not null)
+        if (arguments is { ValueKind: JsonValueKind.Array } json)
         {
-            foreach (var (key, value) in arguments)
+            // Positional CLI arguments
+            foreach (var element in json.EnumerateArray())
             {
-                if (value is bool boolValue)
+                if (element.ValueKind != JsonValueKind.String)
                 {
-                    if (boolValue)
-                    {
-                        startInfo.ArgumentList.Add(NormalizeKey(key));
-                    }
-                }
-                else if (value is not null)
-                {
-                    startInfo.ArgumentList.Add(NormalizeKey(key));
-                    startInfo.ArgumentList.Add(value.ToString()!);
+                    throw new InvalidOperationException(
+                        $"File-based skill scripts only accept string CLI arguments but received a JSON element of kind '{element.ValueKind}'. " +
+                        "All array elements must be JSON strings.");
                 }
+
+                startInfo.ArgumentList.Add(element.GetString()!);
             }
         }
+        else if (arguments is not null && arguments.Value.ValueKind != JsonValueKind.Null && arguments.Value.ValueKind != JsonValueKind.Undefined)
+        {
+            throw new InvalidOperationException(
+                $"Expected a JSON array of CLI arguments but received {arguments.Value.ValueKind}. " +
+                "File-based skill scripts expect positional arguments as a JSON array of strings.");
+        }
 
         Process? process = null;
         try
@@ -128,10 +132,4 @@ internal static class SubprocessScriptRunner
             process?.Dispose();
         }
     }
-
-    /// <summary>
-    /// Normalizes a parameter key to a consistent --flag format.
-    /// Models may return keys with or without leading dashes (e.g., "value" vs "--value").
-    /// </summary>
-    private static string NormalizeKey(string key) => "--" + key.TrimStart('-');
 }

dotnet/samples/02-agents/Agents/Agent_Step20_DynamicFunctionTools/Agent_Step20_DynamicFunctionTools.csproj

@@ -0,0 +1,20 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworks>net10.0</TargetFrameworks>
+
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Azure.AI.OpenAI" />
+    <PackageReference Include="Azure.Identity" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.OpenAI\Microsoft.Agents.AI.OpenAI.csproj" />
+  </ItemGroup>
+
+</Project>

dotnet/samples/02-agents/Agents/Agent_Step20_DynamicFunctionTools/Program.cs

@@ -0,0 +1,281 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+// This sample demonstrates how to dynamically expand the set of function tools available to an
+// agent during a function-calling loop. The agent starts with a single "RequestTools" function.
+// When the model calls RequestTools with a description of the capabilities needed, the function
+// uses the ambient FunctionInvocationContext to add new tools to ChatOptions.Tools. The agent
+// can then use the newly added tools in subsequent iterations of the same function-calling loop.
+
+using System.ComponentModel;
+using Azure.AI.OpenAI;
+using Azure.Identity;
+using Microsoft.Agents.AI;
+using Microsoft.Extensions.AI;
+
+var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT") ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");
+var deploymentName = Environment.GetEnvironmentVariable("AZURE_OPENAI_DEPLOYMENT_NAME") ?? "gpt-5.4-mini";
+
+// Pre-defined tool implementations that can be loaded on demand.
+[Description("Get the current weather for a city.")]
+static string GetWeather([Description("The city name.")] string city) =>
+    city.ToUpperInvariant() switch
+    {
+        "SEATTLE" => "Seattle: 55°F, cloudy with light rain.",
+        "NEW YORK" => "New York: 72°F, sunny and warm.",
+        "LONDON" => "London: 48°F, overcast with fog.",
+        _ => $"{city}: weather data not available, please provide one of the following city names: 'Seattle', 'New York', 'London'."
+    };
+
+[Description("Get the current local time for a city.")]
+static string GetTime([Description("The city name.")] string city) =>
+    city.ToUpperInvariant() switch
+    {
+        "SEATTLE" => "Seattle: 9:00 AM PST",
+        "NEW YORK" => "New York: 12:00 PM EST",
+        "LONDON" => "London: 5:00 PM GMT",
+        _ => $"{city}: time data not available, please provide one of the following city names: 'Seattle', 'New York', 'London'."
+    };
+
+[Description("Convert a temperature from Fahrenheit to Celsius.")]
+static string ConvertFahrenheitToCelsius([Description("The temperature in Fahrenheit.")] double fahrenheit) =>
+    $"{fahrenheit}°F = {(fahrenheit - 32) * 5 / 9:F1}°C";
+
+// A registry of tool sets that can be loaded by description keyword.
+Dictionary<string, List<AITool>> toolCatalog = new(StringComparer.OrdinalIgnoreCase)
+{
+    ["weather"] = [AIFunctionFactory.Create(GetWeather, name: "GetWeather")],
+    ["time"] = [AIFunctionFactory.Create(GetTime, name: "GetTime")],
+    ["temperature"] = [AIFunctionFactory.Create(ConvertFahrenheitToCelsius, name: "ConvertFahrenheitToCelsius")],
+};
+
+// The RequestTools function uses the ambient FunctionInvocationContext to add tools dynamically.
+AIFunction requestToolsFunction = AIFunctionFactory.Create(
+    [Description("Request additional tools to be loaded based on a description of the functionality needed. " +
+                 "Call this when you need capabilities that are not yet available in your current tool set.")] (
+        [Description("A description of the functionality required, e.g. 'weather', 'time', or 'temperature conversion'.")] string description
+    ) =>
+    {
+        // Access the ambient FunctionInvocationContext provided by FunctionInvokingChatClient.
+        var context = FunctionInvokingChatClient.CurrentContext
+            ?? throw new InvalidOperationException("No ambient FunctionInvocationContext available.");
+
+        var tools = context.Options?.Tools;
+        if (tools is null)
+        {
+            return "Unable to register new tools: ChatOptions.Tools is not available.";
+        }
+
+        // Find matching tool sets from the catalog.
+        List<string> addedToolNames = [];
+        foreach (var kvp in toolCatalog)
+        {
+            var keyword = kvp.Key;
+            var catalogTools = kvp.Value;
+            if (description.Contains(keyword, StringComparison.OrdinalIgnoreCase))
+            {
+                foreach (var tool in catalogTools)
+                {
+                    // Avoid adding duplicates.
+                    if (tool is AIFunction fn && !tools.Any(t => t is AIFunction existing && existing.Name == fn.Name))
+                    {
+                        tools.Add(tool);
+                        addedToolNames.Add(fn.Name);
+                    }
+                }
+            }
+        }
+
+        return addedToolNames.Count > 0
+            ? "Successfully loaded tools"
+            : $"No tools matched the description '{description}'. Available categories: {string.Join(", ", toolCatalog.Keys)}.";
+    },
+    name: "RequestTools");
+
+// Create the agent with only the RequestTools function initially.
+// Insert chat client middleware that logs the tools available on each LLM call,
+// making the dynamic expansion visible in the console output.
+// WARNING: DefaultAzureCredential is convenient for development but requires careful consideration in production.
+// In production, consider using a specific credential (e.g., ManagedIdentityCredential) to avoid
+// latency issues, unintended credential probing, and potential security risks from fallback mechanisms.
+AIAgent agent = new AzureOpenAIClient(
+    new Uri(endpoint),
+    new DefaultAzureCredential())
+    .GetChatClient(deploymentName)
+    .AsIChatClient()
+    .AsBuilder()
+    .Use(getResponseFunc: ToolLoggingMiddleware, getStreamingResponseFunc: ToolLoggingStreamingMiddleware)
+    .BuildAIAgent(
+        instructions: """
+            You are a helpful assistant. You start with limited tools.
+            When you need functionality that you don't currently have, call RequestTools with a description
+            of what you need. After new tools are loaded, use them to answer the user's question.
+            """,
+        tools: [requestToolsFunction]);
+
+// Run a conversation that triggers dynamic tool expansion.
+Console.WriteLine("=== Dynamic Function Tools Sample ===\n");
+
+string[] prompts =
+[
+    "What's the weather like in Seattle and London?",
+    "What time is it in New York?",
+    "Can you convert those temperatures to Celsius?"
+];
+
+// --- Non-Streaming Mode ---
+Console.ForegroundColor = ConsoleColor.Yellow;
+Console.WriteLine("=== Non-Streaming Mode ===");
+Console.ResetColor();
+Console.WriteLine();
+
+AgentSession session = await agent.CreateSessionAsync();
+
+foreach (var prompt in prompts)
+{
+    Console.ForegroundColor = ConsoleColor.Green;
+    Console.Write("[User] ");
+    Console.ResetColor();
+    Console.WriteLine(prompt);
+
+    var response = await agent.RunAsync(prompt, session);
+
+    // Print all message contents including tool calls, tool results, and text.
+    foreach (var message in response.Messages)
+    {
+        foreach (var content in message.Contents)
+        {
+            switch (content)
+            {
+                case FunctionCallContent functionCall:
+                    Console.ForegroundColor = ConsoleColor.Yellow;
+                    Console.WriteLine($"  [Tool Call] {functionCall.Name}({string.Join(", ", functionCall.Arguments?.Select(a => $"{a.Key}: {a.Value}") ?? [])})");
+                    Console.ResetColor();
+                    break;
+
+                case FunctionResultContent functionResult:
+                    Console.ForegroundColor = ConsoleColor.DarkYellow;
+                    Console.WriteLine($"  [Tool Result] {functionResult.CallId} => {functionResult.Result}");
+                    Console.ResetColor();
+                    break;
+
+                case TextContent textContent when !string.IsNullOrWhiteSpace(textContent.Text):
+                    Console.ForegroundColor = ConsoleColor.Cyan;
+                    Console.Write("[Agent] ");
+                    Console.ResetColor();
+                    Console.WriteLine(textContent.Text);
+                    break;
+            }
+        }
+    }
+
+    Console.WriteLine();
+}
+
+// --- Streaming Mode ---
+Console.ForegroundColor = ConsoleColor.Yellow;
+Console.WriteLine("=== Streaming Mode ===");
+Console.ResetColor();
+Console.WriteLine();
+
+AgentSession streamingSession = await agent.CreateSessionAsync();
+
+foreach (var prompt in prompts)
+{
+    Console.ForegroundColor = ConsoleColor.Green;
+    Console.Write("[User] ");
+    Console.ResetColor();
+    Console.WriteLine(prompt);
+
+    bool inAgentText = false;
+
+    await foreach (var update in agent.RunStreamingAsync(prompt, streamingSession))
+    {
+        foreach (var content in update.Contents)
+        {
+            switch (content)
+            {
+                case FunctionCallContent functionCall:
+                    if (inAgentText)
+                    {
+                        Console.WriteLine();
+                        inAgentText = false;
+                    }
+
+                    Console.ForegroundColor = ConsoleColor.Yellow;
+                    Console.WriteLine($"  [Tool Call] {functionCall.Name}({string.Join(", ", functionCall.Arguments?.Select(a => $"{a.Key}: {a.Value}") ?? [])})");
+                    Console.ResetColor();
+                    break;
+
+                case FunctionResultContent functionResult:
+                    Console.ForegroundColor = ConsoleColor.DarkYellow;
+                    Console.WriteLine($"  [Tool Result] {functionResult.CallId} => {functionResult.Result}");
+                    Console.ResetColor();
+                    break;
+
+                case TextContent textContent when !string.IsNullOrWhiteSpace(textContent.Text):
+                    if (!inAgentText)
+                    {
+                        Console.ForegroundColor = ConsoleColor.Cyan;
+                        Console.Write("[Agent] ");
+                        Console.ResetColor();
+                        inAgentText = true;
+                    }
+
+                    Console.Write(textContent.Text);
+                    break;
+            }
+        }
+    }
+
+    if (inAgentText)
+    {
+        Console.WriteLine();
+    }
+
+    Console.WriteLine();
+}
+
+// Chat client middleware that logs the number and names of tools on each LLM request.
+async Task<ChatResponse> ToolLoggingMiddleware(
+    IEnumerable<ChatMessage> messages,
+    ChatOptions? options,
+    IChatClient innerChatClient,
+    CancellationToken cancellationToken)
+{
+    LogTools(options);
+
+    return await innerChatClient.GetResponseAsync(messages, options, cancellationToken);
+}
+
+// Streaming version of the tool logging middleware.
+async IAsyncEnumerable<ChatResponseUpdate> ToolLoggingStreamingMiddleware(
+    IEnumerable<ChatMessage> messages,
+    ChatOptions? options,
+    IChatClient innerChatClient,
+    [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
+{
+    LogTools(options);
+
+    await foreach (var update in innerChatClient.GetStreamingResponseAsync(messages, options, cancellationToken))
+    {
+        yield return update;
+    }
+}
+
+// Shared helper to log the current tool set.
+void LogTools(ChatOptions? options)
+{
+    if (options?.Tools is { Count: > 0 } tools)
+    {
+        var toolNames = tools.OfType<AIFunction>().Select(t => t.Name);
+        Console.ForegroundColor = ConsoleColor.DarkGray;
+        Console.WriteLine($"  [Middleware] LLM call with {tools.Count} tool(s): {string.Join(", ", toolNames)}");
+        Console.ResetColor();
+    }
+    else
+    {
+        Console.ForegroundColor = ConsoleColor.DarkGray;
+        Console.WriteLine("  [Middleware] LLM call with 0 tools");
+        Console.ResetColor();
+    }
+}

dotnet/samples/02-agents/Agents/Agent_Step20_DynamicFunctionTools/README.md

@@ -0,0 +1,38 @@
+# Dynamic Function Tools
+
+This sample demonstrates how to dynamically expand the set of function tools available to an agent during a function-calling loop.
+
+## What it demonstrates
+
+- The agent starts with only a single `RequestTools` function
+- When the model needs capabilities it doesn't have, it calls `RequestTools` with a description of the functionality needed
+- The `RequestTools` function uses the ambient `FunctionInvokingChatClient.CurrentContext` to access `ChatOptions.Tools` and add new tools at runtime
+- The agent then uses the newly added tools in subsequent iterations of the same function-calling loop
+
+## How it works
+
+1. A tool catalog maps keywords (e.g. "weather", "time", "temperature") to pre-built `AIFunction` instances
+2. The `RequestTools` function matches the description against catalog keywords and adds matching tools to `ChatOptions.Tools`
+3. `FunctionInvokingChatClient` automatically picks up the new tools on the next iteration of its loop
+
+## Prerequisites
+
+- .NET 10 SDK or later
+- Azure OpenAI service endpoint and deployment configured
+- Azure CLI installed and authenticated (for Azure credential authentication)
+- User has the `Cognitive Services OpenAI Contributor` role for the Azure OpenAI resource
+
+## Running the sample
+
+Set the required environment variables:
+
+```powershell
+$env:AZURE_OPENAI_ENDPOINT="https://your-resource.openai.azure.com/"
+$env:AZURE_OPENAI_DEPLOYMENT_NAME="gpt-5.4-mini"  # Optional, defaults to gpt-5.4-mini
+```
+
+Run the sample:
+
+```powershell
+dotnet run
+```

dotnet/samples/02-agents/Agents/README.md

@@ -46,6 +46,7 @@ Before you begin, ensure you have the following prerequisites:
 |[Providing additional AI Context to an agent using multiple AIContextProviders](./Agent_Step17_AdditionalAIContext/)|This sample demonstrates how to inject additional AI context into a ChatClientAgent using multiple custom AIContextProvider components that are attached to the agent.|
 |[Using compaction pipeline with an agent](./Agent_Step18_CompactionPipeline/)|This sample demonstrates how to use a compaction pipeline to efficiently limit the size of the conversation history for an agent.|
 |[In-function-loop checkpointing](./Agent_Step19_InFunctionLoopCheckpointing/)|This sample demonstrates how to persist chat history after each service call during a tool-calling loop, enabling crash recovery and mid-run observability.|
+|[Dynamic function tools](./Agent_Step20_DynamicFunctionTools/)|This sample demonstrates how to dynamically expand the set of function tools available to an agent during a function-calling loop using the ambient FunctionInvocationContext.|
 
 ## Running the samples from the console
 

dotnet/samples/02-agents/AgentsWithFoundry/Agent_Step25_ToolboxServerSideTools/Agent_Step25_ToolboxServerSideTools.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworks>net10.0</TargetFrameworks>
+
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Foundry.Hosting\Microsoft.Agents.AI.Foundry.Hosting.csproj" />
+    <PackageReference Include="Azure.AI.Projects" VersionOverride="2.1.0-beta.1" />
+  </ItemGroup>
+
+</Project>

dotnet/samples/02-agents/AgentsWithFoundry/Agent_Step25_ToolboxServerSideTools/Program.cs

@@ -0,0 +1,148 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+// This sample shows how to load a Foundry toolbox and pass its tools as server-side
+// tools when creating an agent. The Foundry platform handles tool execution — the agent
+// process does not invoke tools locally.
+
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using Azure.AI.Projects;
+using Azure.AI.Projects.Agents;
+using Azure.Identity;
+using Microsoft.Agents.AI;
+using OpenAI.Responses;
+
+#pragma warning disable OPENAI001 // Experimental API
+#pragma warning disable AAIP001  // AgentToolboxes is experimental
+#pragma warning disable CS8321   // Local functions may be commented-out alternatives
+
+// Replace with your own Foundry toolbox name.
+const string ToolboxName = "research_toolbox";
+// Used only by CombineToolboxes — swap in a second toolbox you own.
+const string SecondToolboxName = "analysis_toolbox";
+// Replace with any question that exercises the tools configured in your toolbox.
+const string Query = "Introduce yourself and briefly describe the tools you can use to help me.";
+
+string endpoint = Environment.GetEnvironmentVariable("FOUNDRY_PROJECT_ENDPOINT")
+    ?? throw new InvalidOperationException("Set FOUNDRY_PROJECT_ENDPOINT to your Foundry project endpoint.");
+string model = Environment.GetEnvironmentVariable("FOUNDRY_MODEL") ?? "gpt-5.4-mini";
+
+// WARNING: DefaultAzureCredential is convenient for development but requires careful consideration in production.
+// In production, consider using a specific credential (e.g., ManagedIdentityCredential) to avoid
+// latency issues, unintended credential probing, and potential security risks from fallback mechanisms.
+var projectClient = new AIProjectClient(new Uri(endpoint), new DefaultAzureCredential());
+
+await Main(projectClient, model, endpoint);
+// await CombineToolboxes(projectClient, model, endpoint);
+
+// ---------------------------------------------------------------------------
+// Main: single toolbox
+// ---------------------------------------------------------------------------
+static async Task Main(AIProjectClient projectClient, string model, string endpoint)
+{
+    Console.WriteLine("=== Foundry Toolbox Server-Side Tools Example ===");
+
+    // Comment out if the toolbox already exists in your Foundry project.
+    await CreateSampleToolboxAsync(ToolboxName, endpoint);
+
+    // Omit the version to resolve the toolbox's current default version at runtime.
+    var tools = await projectClient.GetToolboxToolsAsync(ToolboxName);
+
+    AIAgent agent = projectClient
+        .AsAIAgent(
+            model: model,
+            instructions: "You are a research assistant. Use the available tools to answer questions.",
+            tools: tools.ToList());
+
+    Console.WriteLine($"User: {Query}");
+    Console.WriteLine($"Result: {await agent.RunAsync(Query)}\n");
+}
+
+// ---------------------------------------------------------------------------
+// Alternative: combine tools from multiple toolboxes
+// ---------------------------------------------------------------------------
+static async Task CombineToolboxes(AIProjectClient projectClient, string model, string endpoint)
+{
+    Console.WriteLine("=== Combine Toolboxes Example ===");
+
+    // Comment out if the toolboxes already exist in your Foundry project.
+    await CreateSampleToolboxAsync(ToolboxName, endpoint);
+    await CreateSampleToolboxAsync(SecondToolboxName, endpoint);
+
+    var toolboxA = await projectClient.GetToolboxToolsAsync(ToolboxName);
+    var toolboxB = await projectClient.GetToolboxToolsAsync(SecondToolboxName);
+
+    var allTools = toolboxA.Concat(toolboxB).ToList();
+
+    AIAgent agent = projectClient
+        .AsAIAgent(
+            model: model,
+            instructions: "You are a research assistant. Use all available tools to answer questions.",
+            tools: allTools);
+
+    Console.WriteLine($"User: {Query}");
+    Console.WriteLine($"Combined-toolbox result: {await agent.RunAsync(Query)}\n");
+}
+
+// ---------------------------------------------------------------------------
+// Helper: create (or replace) a sample toolbox so the sample works out-of-the-box
+// ---------------------------------------------------------------------------
+static async Task CreateSampleToolboxAsync(string name, string endpoint)
+{
+    // Toolboxes are normally configured in the Foundry portal or a deployment
+    // script, not the application itself. This helper exists so the sample can
+    // be run end-to-end without first setting a toolbox up by hand.
+
+    // The Foundry-Features header is currently required for toolbox CRUD operations.
+    var options = new AgentAdministrationClientOptions();
+    options.AddPolicy(new FoundryFeaturesPolicy("Toolboxes=V1Preview"), PipelinePosition.PerCall);
+    var adminClient = new AgentAdministrationClient(
+        new Uri(endpoint),
+        new DefaultAzureCredential(),
+        options);
+    var toolboxClient = adminClient.GetAgentToolboxes();
+
+    // Delete existing toolbox if present (ignore 404).
+    try
+    {
+        await toolboxClient.DeleteToolboxAsync(name);
+        Console.WriteLine($"Deleted existing toolbox '{name}'");
+    }
+    catch (ClientResultException ex) when (ex.Status == 404)
+    {
+        // Toolbox does not exist — nothing to delete.
+    }
+
+    // Create a fresh version with a single MCP tool.
+    ProjectsAgentTool mcpTool = ProjectsAgentTool.AsProjectTool(ResponseTool.CreateMcpTool(
+        serverLabel: "api-specs",
+        serverUri: new Uri("https://gitmcp.io/Azure/azure-rest-api-specs"),
+        toolCallApprovalPolicy: new McpToolCallApprovalPolicy(GlobalMcpToolCallApprovalPolicy.NeverRequireApproval)));
+
+    var created = (await toolboxClient.CreateToolboxVersionAsync(
+        name: name,
+        tools: [mcpTool],
+        description: "Sample toolbox with an MCP tool — created by Agent_Step25 sample.")).Value;
+
+    Console.WriteLine($"Created toolbox '{created.Name}' v{created.Version} ({created.Tools.Count} tool(s))");
+}
+
+// ---------------------------------------------------------------------------
+// Pipeline policy that adds the Foundry-Features header for toolbox CRUD
+// ---------------------------------------------------------------------------
+internal sealed class FoundryFeaturesPolicy(string feature) : PipelinePolicy
+{
+    private const string FeatureHeader = "Foundry-Features";
+
+    public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+    {
+        message.Request.Headers.Add(FeatureHeader, feature);
+        ProcessNext(message, pipeline, currentIndex);
+    }
+
+    public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+    {
+        message.Request.Headers.Add(FeatureHeader, feature);
+        return ProcessNextAsync(message, pipeline, currentIndex);
+    }
+}

dotnet/samples/02-agents/AgentsWithFoundry/Agent_Step25_ToolboxServerSideTools/README.md

@@ -0,0 +1,46 @@
+# Agent_Step25_ToolboxServerSideTools
+
+This sample demonstrates loading a named Foundry toolbox and passing its tools as
+**server-side tools** when creating an agent via `AsAIAgent()`.
+
+When tools from a toolbox are passed this way, they are sent as tool definitions in
+the Responses API request. The Foundry platform handles tool execution — the agent
+process does not invoke tools locally.
+
+This is the dotnet equivalent of the Python sample:
+`python/samples/02-agents/providers/foundry/foundry_chat_client_with_toolbox.py`
+
+## Prerequisites
+
+- A Microsoft Foundry project
+- `AZURE_AI_PROJECT_ENDPOINT` environment variable set to your Foundry project endpoint
+- `AZURE_AI_MODEL_DEPLOYMENT_NAME` environment variable set (defaults to `gpt-5.4-mini`)
+
+The sample recreates the toolbox on each run, replacing any existing toolbox with
+the same name. Comment out the `CreateSampleToolboxAsync` call if you want to keep
+an existing toolbox unchanged.
+
+## How it works
+
+1. `projectClient.GetToolboxVersionAsync(name)` fetches the toolbox definition from the
+   Foundry project API (resolving the default version if none is specified)
+2. `ToolboxVersion.ToAITools()` converts each tool definition to an `AITool` instance
+3. The tools are passed to `AsAIAgent(tools: ...)` which includes them in the Responses
+   API request as server-side tool definitions
+
+For a one-liner, use `projectClient.GetToolboxToolsAsync(name)` to fetch and convert in one call.
+
+## Sample flows
+
+| Flow | Description |
+|------|-------------|
+| `Main` (default) | Loads a single toolbox and runs an agent with its tools |
+| `CombineToolboxes` | Loads two toolboxes and merges their tools into one agent |
+
+Uncomment the desired flow in the top-level statements to try each one.
+
+## Running the sample
+
+```bash
+dotnet run
+```

dotnet/samples/03-workflows/Declarative/InvokeHttpRequest/InvokeHttpRequest.csproj

@@ -0,0 +1,38 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworks>net10.0</TargetFrameworks>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <InjectIsExternalInitOnLegacy>true</InjectIsExternalInitOnLegacy>
+    <InjectSharedFoundryAgents>true</InjectSharedFoundryAgents>
+    <InjectSharedWorkflowsExecution>true</InjectSharedWorkflowsExecution>
+    <InjectSharedWorkflowsSettings>true</InjectSharedWorkflowsSettings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Configuration" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" />
+    <PackageReference Include="Microsoft.Extensions.Logging" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Workflows.Declarative\Microsoft.Agents.AI.Workflows.Declarative.csproj" />
+    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Workflows.Declarative.Foundry\Microsoft.Agents.AI.Workflows.Declarative.Foundry.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Include="InvokeHttpRequest.yaml">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
+  </ItemGroup>
+
+</Project>

dotnet/samples/03-workflows/Declarative/InvokeHttpRequest/InvokeHttpRequest.yaml

@@ -0,0 +1,76 @@
+#
+# This workflow demonstrates using HttpRequestAction to call a REST API directly
+# from the workflow without going through an AI agent first.
+#
+# HttpRequestAction allows workflows to:
+# - Fetch data from external HTTP endpoints
+# - Store the parsed response in workflow variables for later use
+# - Add the response body to the conversation so a downstream agent can
+#   answer questions based on it
+#
+# This sample fetches public metadata for the dotnet/runtime repository from
+# the GitHub REST API (no authentication required) and uses an agent to
+# answer follow-up questions about it.
+#
+# Example input:
+# How many subscribers does the repository have?
+#
+kind: Workflow
+trigger:
+
+  kind: OnConversationStart
+  id: workflow_invoke_http_request_demo
+  actions:
+
+    # Capture the original user message for input to the follow-up agent.
+    - kind: SetVariable
+      id: set_user_message
+      variable: Local.InputMessage
+      value: =System.LastMessage
+
+    # Set the repository org/name used to form the request URL.
+    - kind: SetVariable
+      id: set_repo_name
+      variable: Local.RepoName
+      value: microsoft/agent-framework
+
+    # Invoke the GitHub repo API. The response body is parsed into Local.RepoInfo
+    # and also added to the conversation (via conversationId) so the agent below
+    # can answer questions based on it.
+    - kind: HttpRequestAction
+      id: fetch_repo_info
+      conversationId: =System.ConversationId
+      method: GET
+      url: =Concatenate("https://api.github.com/repos/", Local.RepoName)
+      headers:
+        Accept: application/vnd.github+json
+        User-Agent: agent-framework-sample
+      response: Local.RepoInfo
+
+    # Display a confirmation message showing key fields from the parsed response.
+    - kind: SendMessage
+      id: show_repo_summary
+      message: "Fetched repo: visibility={Local.RepoInfo.visibility}, description={Local.RepoInfo.description}"
+
+    # Use the agent to summarize the repo using the conversation context.
+    - kind: InvokeAzureAgent
+      id: summarize_repo
+      conversationId: =System.ConversationId
+      agent:
+        name: GitHubRepoInfoAgent
+      input:
+        messages: =UserMessage("Please provide a brief summary of this GitHub repository based on the data already in the conversation.")
+      output:
+        autoSend: true
+        messages: Local.AgentResponse
+
+    # Allow the user to ask follow-up questions about the repo in a loop.
+    - kind: InvokeAzureAgent
+      id: invoke_followup
+      conversationId: =System.ConversationId
+      agent:
+        name: GitHubRepoInfoAgent
+      input:
+        messages: =Local.InputMessage
+        externalLoop:
+          when: =Upper(System.LastMessage.Text) <> "EXIT"

dotnet/samples/03-workflows/Declarative/InvokeHttpRequest/Program.cs

@@ -0,0 +1,95 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Azure.AI.Projects;
+using Azure.AI.Projects.Agents;
+using Azure.Identity;
+using Microsoft.Agents.AI.Workflows.Declarative;
+using Microsoft.Extensions.Configuration;
+using Shared.Foundry;
+using Shared.Workflows;
+
+namespace Demo.Workflows.Declarative.InvokeHttpRequest;
+
+/// <summary>
+/// Demonstrates a workflow that uses HttpRequestAction to call a REST API
+/// directly from the workflow.
+/// </summary>
+/// <remarks>
+/// <para>
+/// The HttpRequestAction allows workflows to issue HTTP requests and:
+/// </para>
+/// <list type="bullet">
+/// <item>Fetch data from external REST endpoints</item>
+/// <item>Store the parsed response in workflow variables</item>
+/// <item>Add the response body to the conversation so an agent can answer
+///       questions based on it</item>
+/// </list>
+/// <para>
+/// This sample fetches public metadata for the dotnet/runtime repository from
+/// the GitHub REST API (no authentication required) and uses a Foundry agent
+/// to answer follow-up questions about it. Type "EXIT" to end the conversation.
+/// </para>
+/// <para>
+/// See the README.md file in the parent folder (../README.md) for detailed
+/// information about the configuration required to run this sample.
+/// </para>
+/// </remarks>
+internal sealed class Program
+{
+    public static async Task Main(string[] args)
+    {
+        // Initialize configuration
+        IConfiguration configuration = Application.InitializeConfig();
+        Uri foundryEndpoint = new(configuration.GetValue(Application.Settings.FoundryEndpoint));
+
+        // Ensure sample agent exists in Foundry. The agent has no tools - it answers
+        // questions about the GitHub repository using only the JSON data that the
+        // HttpRequestAction adds to the conversation.
+        await CreateAgentAsync(foundryEndpoint, configuration);
+
+        // Get input from command line or console
+        string workflowInput = Application.GetInput(args);
+
+        // The default HttpRequestHandler is sufficient for this sample because the
+        // GitHub REST endpoint used here does not require authentication. For
+        // authenticated endpoints, supply a custom Func<HttpRequestInfo, ..., HttpClient?>
+        // to DefaultHttpRequestHandler so each request can be routed through a
+        // pre-configured (cached) HttpClient with the appropriate credentials.
+        await using DefaultHttpRequestHandler httpRequestHandler = new();
+
+        // Create the workflow factory with the HTTP request handler
+        WorkflowFactory workflowFactory = new("InvokeHttpRequest.yaml", foundryEndpoint)
+        {
+            HttpRequestHandler = httpRequestHandler
+        };
+
+        // Execute the workflow
+        WorkflowRunner runner = new() { UseJsonCheckpoints = true };
+        await runner.ExecuteAsync(workflowFactory.CreateWorkflow, workflowInput);
+    }
+
+    private static async Task CreateAgentAsync(Uri foundryEndpoint, IConfiguration configuration)
+    {
+        // WARNING: DefaultAzureCredential is convenient for development but requires careful consideration in production.
+        AIProjectClient aiProjectClient = new(foundryEndpoint, new DefaultAzureCredential());
+
+        await aiProjectClient.CreateAgentAsync(
+            agentName: "GitHubRepoInfoAgent",
+            agentDefinition: DefineAgent(configuration),
+            agentDescription: "Answers questions about a GitHub repository using HTTP response data in the conversation");
+    }
+
+    private static DeclarativeAgentDefinition DefineAgent(IConfiguration configuration)
+    {
+        return new DeclarativeAgentDefinition(configuration.GetValue(Application.Settings.FoundryModel))
+        {
+            Instructions =
+                """
+                Answer the user's questions about the GitHub repository using only the
+                JSON data already present in the conversation history.
+                If the answer is not contained in the conversation, say so plainly
+                rather than guessing. Be concise and helpful.
+                """
+        };
+    }
+}

dotnet/samples/04-hosting/DurableWorkflows/AzureFunctions/01_SequentialWorkflow/README.md

@@ -65,6 +65,53 @@ Workflow orchestration started for CancelOrder. Orchestration runId: abc123def45
 >
 > If not provided, a unique run ID is auto-generated.
 
+### Wait for the Workflow Result
+
+By default, the HTTP endpoint returns `202 Accepted` immediately with the run ID. If you want to wait for the workflow to complete and get the result in the response, add the `x-ms-wait-for-response: true` header:
+
+Bash (Linux/macOS/WSL):
+
+```bash
+curl -X POST http://localhost:7071/api/workflows/CancelOrder/run \
+    -H "Content-Type: text/plain" \
+    -H "x-ms-wait-for-response: true" \
+    -d "12345"
+```
+
+PowerShell:
+
+```powershell
+Invoke-RestMethod -Method Post `
+    -Uri http://localhost:7071/api/workflows/CancelOrder/run `
+    -ContentType text/plain `
+    -Headers @{ "x-ms-wait-for-response" = "true" } `
+    -Body "12345"
+```
+
+The response will contain the workflow result as plain text (200 OK):
+
+```text
+Cancellation email sent for order 12345 to jerry@example.com.
+```
+
+To get the result as JSON, also include the `Accept: application/json` header:
+
+```bash
+curl -X POST http://localhost:7071/api/workflows/CancelOrder/run \
+    -H "Content-Type: text/plain" \
+    -H "x-ms-wait-for-response: true" \
+    -H "Accept: application/json" \
+    -d "12345"
+```
+
+```json
+{
+    "runId": "abc123def456",
+    "workflowStatus": "Completed",
+    "result": "Cancellation email sent for order 12345 to jerry@example.com."
+}
+```
+
 In the function app logs, you will see the sequential execution of each executor:
 
 ```text

dotnet/samples/04-hosting/DurableWorkflows/AzureFunctions/01_SequentialWorkflow/demo.http

@@ -7,6 +7,21 @@ Content-Type: text/plain
 
 12345
 
+### Cancel an order and wait for the result
+POST {{authority}}/api/workflows/CancelOrder/run
+Content-Type: text/plain
+x-ms-wait-for-response: true
+
+12345
+
+### Cancel an order and wait for the result (JSON response)
+POST {{authority}}/api/workflows/CancelOrder/run
+Content-Type: text/plain
+Accept: application/json
+x-ms-wait-for-response: true
+
+12345
+
 ### Cancel an order with a custom run ID
 POST {{authority}}/api/workflows/CancelOrder/run?runId=my-custom-id-123
 Content-Type: text/plain
@@ -19,6 +34,13 @@ Content-Type: text/plain
 
 12345
 
+### Get order status and wait for the result
+POST {{authority}}/api/workflows/OrderStatus/run
+Content-Type: text/plain
+x-ms-wait-for-response: true
+
+12345
+
 ### Batch cancel orders with a complex JSON input
 POST {{authority}}/api/workflows/BatchCancelOrders/run
 Content-Type: application/json

dotnet/samples/04-hosting/FoundryHostedAgents/invocations/Hosted-Invocations-EchoAgent/Hosted-Invocations-EchoAgent.csproj

@@ -13,6 +13,8 @@
   <ItemGroup>
     <PackageReference Include="Azure.AI.AgentServer.Invocations" />
     <PackageReference Include="DotNetEnv" />
+    <PackageReference Include="OpenTelemetry.Api" />
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" />
   </ItemGroup>
 
   <!-- For contributors: uses ProjectReference to build against local source -->

dotnet/src/Aspire.Hosting.AgentFramework.DevUI/Aspire.Hosting.AgentFramework.DevUI.csproj

@@ -2,14 +2,22 @@
 
   <PropertyGroup>
     <TargetFrameworks>$(TargetFrameworksCore)</TargetFrameworks>
-    <IsPackable>true</IsPackable>
-    <PackageTags>aspire integration hosting agent-framework devui ai agents</PackageTags>
-    <Description>Microsoft Agent Framework DevUI support for Aspire.</Description>
+    <VersionSuffix>preview</VersionSuffix>
     <!-- Suppress analyzer warnings for Aspire integration code -->
     <!-- IL2026/IL3050: Suppress trimming/AOT warnings - DevUI is a dev-only tool not intended for AOT -->
     <NoWarn>$(NoWarn);CA1873;RCS1061;VSTHRD002;IL2026;IL3050</NoWarn>
   </PropertyGroup>
 
+  <Import Project="$(RepoRoot)/dotnet/nuget/nuget-package.props" />
+
+  <PropertyGroup>
+    <!-- NuGet Package Settings -->
+    <Title>Microsoft Agent Framework DevUI for Aspire</Title>
+    <PackageTags>aspire integration hosting agent-framework devui ai agents</PackageTags>
+    <Description>Microsoft Agent Framework DevUI support for Aspire.</Description>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
+
   <ItemGroup>
     <InternalsVisibleTo Include="Aspire.Hosting.AgentFramework.DevUI.UnitTests" />
   </ItemGroup>
@@ -22,4 +30,7 @@
     <PackageReference Include="Aspire.Hosting" />
   </ItemGroup>
 
+  <ItemGroup>
+    <None Include="README.md" Pack="true" PackagePath="/" />
+  </ItemGroup>
 </Project>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/AIProjectClientToolboxExtensions.cs

@@ -0,0 +1,57 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Agents.AI.Foundry.Hosting;
+using Microsoft.Extensions.AI;
+using Microsoft.Shared.DiagnosticIds;
+using Microsoft.Shared.Diagnostics;
+
+#pragma warning disable OPENAI001
+#pragma warning disable AAIP001 // AgentToolboxes is experimental in Azure.AI.Projects.Agents
+
+namespace Azure.AI.Projects;
+
+/// <summary>
+/// Provides extension methods on <see cref="AIProjectClient"/> for fetching
+/// Foundry toolbox definitions as server-side tools.
+/// </summary>
+/// <remarks>
+/// These extensions mirror Python's <c>FoundryChatClient.get_toolbox()</c> pattern,
+/// allowing a single call on the project client to retrieve tools ready for use
+/// with <c>AsAIAgent(model, instructions, tools: ...)</c>.
+/// </remarks>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
+public static class AIProjectClientToolboxExtensions
+{
+    /// <summary>
+    /// Fetches a toolbox from the Foundry project and returns its tools as <see cref="AITool"/> instances
+    /// ready for use as server-side tools in the Responses API.
+    /// </summary>
+    /// <param name="projectClient">The <see cref="AIProjectClient"/> to use. Cannot be <see langword="null"/>.</param>
+    /// <param name="name">The name of the toolbox to fetch.</param>
+    /// <param name="version">
+    /// The specific toolbox version to fetch. When <see langword="null"/>, the toolbox's
+    /// default version is resolved automatically.
+    /// </param>
+    /// <param name="cancellationToken">A token to monitor for cancellation requests.</param>
+    /// <returns>A read-only list of <see cref="AITool"/> instances from the toolbox.</returns>
+    /// <exception cref="System.ArgumentNullException">
+    /// Thrown when <paramref name="projectClient"/> or <paramref name="name"/> is <see langword="null"/>.
+    /// </exception>
+    public static async Task<IReadOnlyList<AITool>> GetToolboxToolsAsync(
+        this AIProjectClient projectClient,
+        string name,
+        string? version = null,
+        CancellationToken cancellationToken = default)
+    {
+        Throw.IfNull(projectClient);
+        Throw.IfNullOrWhitespace(name);
+
+        var toolboxClient = projectClient.AgentAdministrationClient.GetAgentToolboxes();
+        var toolboxVersion = await FoundryToolbox.GetToolboxVersionCoreAsync(toolboxClient, name, version, cancellationToken).ConfigureAwait(false);
+        return toolboxVersion.ToAITools();
+    }
+}

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/AgentFrameworkResponseHandler.cs

@@ -297,6 +297,7 @@ public class AgentFrameworkResponseHandler : ResponseHandler
             var agent = this._serviceProvider.GetKeyedService<AIAgent>(agentName);
             if (agent is not null)
             {
+                FoundryHostingExtensions.TryApplyUserAgent(agent);
                 return FoundryHostingExtensions.ApplyOpenTelemetry(agent);
             }
 
@@ -310,12 +311,13 @@ public class AgentFrameworkResponseHandler : ResponseHandler
         var defaultAgent = this._serviceProvider.GetService<AIAgent>();
         if (defaultAgent is not null)
         {
+            FoundryHostingExtensions.TryApplyUserAgent(defaultAgent);
             return FoundryHostingExtensions.ApplyOpenTelemetry(defaultAgent);
         }
 
         var errorMessage = string.IsNullOrEmpty(agentName)
             ? "No agent name specified in the request (via agent.name or metadata[\"entity_id\"]) and no default AIAgent is registered."
-            : $"Agent '{agentName}' not found. Ensure it is registered via AddAIAgent(\"{agentName}\", ...) or as a default AIAgent.";
+            : $"Agent '{agentName}' not found. Ensure it is registered via AddFoundryResponses(services, agent) or services.AddKeyedSingleton<AIAgent>(\"{agentName}\", ...).";
 
         throw new InvalidOperationException(errorMessage);
     }
@@ -352,7 +354,7 @@ public class AgentFrameworkResponseHandler : ResponseHandler
 
         var errorMessage = string.IsNullOrEmpty(agentName)
             ? "No agent name specified in the request (via agent.name or metadata[\"entity_id\"]) and no default AgentSessionStore is registered."
-            : $"Agent '{agentName}' not found. Ensure it is registered via AddAIAgent(\"{agentName}\", ...) or as a default AgentSessionStore.";
+            : $"AgentSessionStore for agent '{agentName}' not found. Ensure it is registered via AddFoundryResponses(services, agent, agentSessionStore) or services.AddKeyedSingleton<AgentSessionStore>(\"{agentName}\", ...).";
 
         throw new InvalidOperationException(errorMessage);
     }

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/DelegatingResponsesClient.cs

@@ -0,0 +1,113 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using OpenAI;
+using OpenAI.Responses;
+
+#pragma warning disable OPENAI001, SCME0001
+
+namespace Microsoft.Agents.AI.Foundry.Hosting;
+
+/// <summary>
+/// A <see cref="ResponsesClient"/> subclass that delegates every protocol-level request to a
+/// wrapped <see cref="ResponsesClient"/>. Before each call, a
+/// <see cref="HostedAgentUserAgentPolicy"/> is added to the per-call
+/// <see cref="RequestOptions"/> so the wrapped client's pipeline appends the hosted-agent
+/// <c>User-Agent</c> segment on the wire.
+/// </summary>
+/// <remarks>
+/// <para>
+/// The streaming overloads MEAI binds via reflection (<c>internal CreateResponseStreamingAsync(CreateResponseOptions, RequestOptions)</c>
+/// and <c>internal GetResponseStreamingAsync(GetResponseOptions, RequestOptions)</c>) bottom out
+/// in calls to the public-virtual non-streaming protocol overloads on <see langword="this"/>. Overriding those
+/// non-streaming overloads is therefore sufficient to intercept both streaming and non-streaming traffic.
+/// </para>
+/// <para>
+/// The base pipeline supplied to <see cref="ResponsesClient(ClientPipeline, OpenAIClientOptions)"/>
+/// is a dummy pipeline whose terminal transport throws if invoked. Every override on this class
+/// delegates to the inner client BEFORE any code path reaches <see cref="ResponsesClient.Pipeline"/>, so the dummy is
+/// never expected to run; the throwing transport surfaces any unexpected escape route loudly.
+/// </para>
+/// </remarks>
+internal sealed class DelegatingResponsesClient : ResponsesClient
+{
+    private readonly ResponsesClient _inner;
+
+    public DelegatingResponsesClient(ResponsesClient inner)
+        : base(BuildDummyPipeline(), new OpenAIClientOptions { Endpoint = inner?.Endpoint })
+    {
+        this._inner = inner ?? throw new ArgumentNullException(nameof(inner));
+    }
+
+    public override async Task<ClientResult> CreateResponseAsync(BinaryContent content, RequestOptions? options = null)
+        => await this._inner.CreateResponseAsync(content, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult CreateResponse(BinaryContent content, RequestOptions? options = null)
+        => this._inner.CreateResponse(content, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> GetResponseAsync(string responseId, IEnumerable<IncludedResponseProperty>? include, bool? stream, int? startingAfter, bool? includeObfuscation, RequestOptions options)
+        => await this._inner.GetResponseAsync(responseId, include, stream, startingAfter, includeObfuscation, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult GetResponse(string responseId, IEnumerable<IncludedResponseProperty>? include, bool? stream, int? startingAfter, bool? includeObfuscation, RequestOptions options)
+        => this._inner.GetResponse(responseId, include, stream, startingAfter, includeObfuscation, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> DeleteResponseAsync(string responseId, RequestOptions options)
+        => await this._inner.DeleteResponseAsync(responseId, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult DeleteResponse(string responseId, RequestOptions options)
+        => this._inner.DeleteResponse(responseId, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> CancelResponseAsync(string responseId, RequestOptions options)
+        => await this._inner.CancelResponseAsync(responseId, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult CancelResponse(string responseId, RequestOptions options)
+        => this._inner.CancelResponse(responseId, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> GetInputTokenCountAsync(string contentType, BinaryContent content, RequestOptions? options = null)
+        => await this._inner.GetInputTokenCountAsync(contentType, content, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult GetInputTokenCount(string contentType, BinaryContent content, RequestOptions? options = null)
+        => this._inner.GetInputTokenCount(contentType, content, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> CompactResponseAsync(string contentType, BinaryContent content, RequestOptions? options = null)
+        => await this._inner.CompactResponseAsync(contentType, content, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult CompactResponse(string contentType, BinaryContent content, RequestOptions? options = null)
+        => this._inner.CompactResponse(contentType, content, AddUserAgentPolicy(options));
+
+    public override async Task<ClientResult> GetResponseInputItemCollectionPageAsync(string responseId, int? limit, string order, string after, string before, RequestOptions options)
+        => await this._inner.GetResponseInputItemCollectionPageAsync(responseId, limit, order, after, before, AddUserAgentPolicy(options)).ConfigureAwait(false);
+
+    public override ClientResult GetResponseInputItemCollectionPage(string responseId, int? limit, string order, string after, string before, RequestOptions options)
+        => this._inner.GetResponseInputItemCollectionPage(responseId, limit, order, after, before, AddUserAgentPolicy(options));
+
+    private static RequestOptions AddUserAgentPolicy(RequestOptions? options)
+    {
+        options ??= new RequestOptions();
+        options.AddPolicy(HostedAgentUserAgentPolicy.Instance, PipelinePosition.PerCall);
+        return options;
+    }
+
+    private static ClientPipeline BuildDummyPipeline()
+    {
+        var options = new ClientPipelineOptions
+        {
+            Transport = new ThrowingTransport(),
+        };
+        return ClientPipeline.Create(options, default, default, default);
+    }
+
+    private sealed class ThrowingTransport : PipelineTransport
+    {
+        private const string Message =
+            "DelegatingResponsesClient transport invoked bypassed the override-and-delegate design. This exception should be unreachable and should never be thrown following the correct usage of DelegatingResponsesClient.";
+
+        protected override PipelineMessage CreateMessageCore() => throw new InvalidOperationException(Message);
+        protected override void ProcessCore(PipelineMessage message) => throw new InvalidOperationException(Message);
+        protected override ValueTask ProcessCoreAsync(PipelineMessage message) => throw new InvalidOperationException(Message);
+    }
+}

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/FoundryToolbox.cs

@@ -0,0 +1,223 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Text.Json.Nodes;
+using System.Threading;
+using System.Threading.Tasks;
+using Azure.AI.Projects.Agents;
+using Microsoft.Extensions.AI;
+using Microsoft.Shared.DiagnosticIds;
+using Microsoft.Shared.Diagnostics;
+using OpenAI.Responses;
+
+#pragma warning disable OPENAI001
+#pragma warning disable AAIP001 // AgentToolboxes is experimental in Azure.AI.Projects.Agents
+#pragma warning disable IL2026 // ModelReaderWriter.Read<ResponseTool> uses reflection; suppressed for Azure SDK model types.
+#pragma warning disable IL3050 // ModelReaderWriter.Read<ResponseTool> requires dynamic code; suppressed for Azure SDK model types.
+
+namespace Microsoft.Agents.AI.Foundry.Hosting;
+
+/// <summary>
+/// Provides methods for fetching Foundry toolbox definitions and converting their tools
+/// to <see cref="AITool"/> instances for use as server-side tools in the Responses API.
+/// </summary>
+/// <remarks>
+/// <para>
+/// When tools from a toolbox are passed to a Foundry agent (e.g. via <c>AsAIAgent(model, instructions, tools: ...)</c>),
+/// they are sent as server-side tool definitions in the Responses API request. The Foundry platform
+/// handles tool execution — the agent process does not invoke tools locally.
+/// </para>
+/// <para>
+/// This is the dotnet equivalent of Python's <c>FoundryChatClient.get_toolbox()</c> pattern.
+/// </para>
+/// </remarks>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
+public static class FoundryToolbox
+{
+    /// <summary>
+    /// Fetches a toolbox version from the Foundry project and returns the raw SDK <see cref="ToolboxVersion"/>.
+    /// </summary>
+    /// <param name="projectEndpoint">The Foundry project endpoint URI.</param>
+    /// <param name="credential">The authentication credential used to access the Foundry project.</param>
+    /// <param name="name">The name of the toolbox to fetch.</param>
+    /// <param name="version">
+    /// The specific toolbox version to fetch. When <see langword="null"/>, the toolbox's
+    /// default version is resolved automatically (requires an additional API call).
+    /// </param>
+    /// <param name="cancellationToken">A token to monitor for cancellation requests.</param>
+    /// <returns>The <see cref="ToolboxVersion"/> containing tool definitions.</returns>
+    /// <exception cref="ArgumentNullException">
+    /// Thrown when <paramref name="projectEndpoint"/>, <paramref name="credential"/>, or <paramref name="name"/> is <see langword="null"/>.
+    /// </exception>
+    /// <exception cref="ClientResultException">Thrown when the Foundry project API returns an error.</exception>
+    public static async Task<ToolboxVersion> GetToolboxVersionAsync(
+        Uri projectEndpoint,
+        AuthenticationTokenProvider credential,
+        string name,
+        string? version = null,
+        CancellationToken cancellationToken = default)
+    {
+        Throw.IfNull(projectEndpoint);
+        Throw.IfNull(credential);
+        Throw.IfNullOrWhitespace(name);
+
+        var toolboxClient = CreateToolboxClient(projectEndpoint, credential);
+        return await GetToolboxVersionCoreAsync(toolboxClient, name, version, cancellationToken).ConfigureAwait(false);
+    }
+
+    /// <summary>
+    /// Fetches a toolbox from the Foundry project and returns its tools as <see cref="AITool"/> instances
+    /// ready for use as server-side tools in the Responses API.
+    /// </summary>
+    /// <param name="projectEndpoint">The Foundry project endpoint URI.</param>
+    /// <param name="credential">The authentication credential used to access the Foundry project.</param>
+    /// <param name="name">The name of the toolbox to fetch.</param>
+    /// <param name="version">
+    /// The specific toolbox version to fetch. When <see langword="null"/>, the toolbox's
+    /// default version is resolved automatically.
+    /// </param>
+    /// <param name="cancellationToken">A token to monitor for cancellation requests.</param>
+    /// <returns>A read-only list of <see cref="AITool"/> instances from the toolbox.</returns>
+    /// <exception cref="ArgumentNullException">
+    /// Thrown when <paramref name="projectEndpoint"/>, <paramref name="credential"/>, or <paramref name="name"/> is <see langword="null"/>.
+    /// </exception>
+    /// <exception cref="ClientResultException">Thrown when the Foundry project API returns an error.</exception>
+    public static async Task<IReadOnlyList<AITool>> GetToolsAsync(
+        Uri projectEndpoint,
+        AuthenticationTokenProvider credential,
+        string name,
+        string? version = null,
+        CancellationToken cancellationToken = default)
+    {
+        var toolboxVersion = await GetToolboxVersionAsync(projectEndpoint, credential, name, version, cancellationToken).ConfigureAwait(false);
+        return toolboxVersion.ToAITools();
+    }
+
+    /// <summary>
+    /// Converts the tools in a <see cref="ToolboxVersion"/> to <see cref="AITool"/> instances
+    /// suitable for use as server-side tools in the Responses API.
+    /// </summary>
+    /// <param name="toolboxVersion">The toolbox version whose tools to convert.</param>
+    /// <returns>A read-only list of <see cref="AITool"/> instances.</returns>
+    /// <exception cref="ArgumentNullException">Thrown when <paramref name="toolboxVersion"/> is <see langword="null"/>.</exception>
+    /// <remarks>
+    /// <para>
+    /// Each <see cref="ProjectsAgentTool"/> in the toolbox is cast to <see cref="ResponseTool"/>
+    /// and converted via <c>AsAITool()</c>. Non-function hosted tools (MCP, web_search,
+    /// code_interpreter, etc.) are included as server-side tool definitions — the Foundry
+    /// platform handles their execution.
+    /// </para>
+    /// <para>
+    /// Non-function tools are sanitized to remove decoration fields (<c>name</c>, <c>description</c>)
+    /// that the toolbox API returns but the Responses API rejects.
+    /// </para>
+    /// </remarks>
+    public static IReadOnlyList<AITool> ToAITools(this ToolboxVersion toolboxVersion)
+    {
+        Throw.IfNull(toolboxVersion);
+
+        if (toolboxVersion.Tools?.Any() != true)
+        {
+            return [];
+        }
+
+        return toolboxVersion.Tools
+            .Select(SanitizeAndConvert)
+            .ToList();
+    }
+
+    #region Internal helpers (visible to unit tests via InternalsVisibleTo)
+
+    /// <summary>
+    /// Sanitizes a <see cref="ProjectsAgentTool"/> by removing decoration fields that the
+    /// toolbox API returns but the Responses API rejects, then converts to <see cref="AITool"/>.
+    /// </summary>
+    /// <remarks>
+    /// The Azure AI Projects toolbox API may return <c>name</c> and <c>description</c> on
+    /// hosted tool objects (MCP, code_interpreter, file_search, etc.). The Responses API
+    /// rejects at least <c>name</c> with "Unknown parameter: 'tools[0].name'". We strip
+    /// these decoration fields for non-function tools. Function tools keep them since
+    /// <c>name</c> and <c>description</c> are expected parts of the function schema.
+    /// </remarks>
+    internal static AITool SanitizeAndConvert(ProjectsAgentTool tool)
+    {
+        var toolJson = ModelReaderWriter.Write(tool, new ModelReaderWriterOptions("J"));
+        var node = JsonNode.Parse(toolJson.ToString());
+        if (node is not JsonObject obj)
+        {
+            return ((ResponseTool)tool).AsAITool();
+        }
+
+        var toolType = obj["type"]?.GetValue<string>();
+
+        // Function tools need name/description — don't strip
+        if (toolType is "function" or "custom")
+        {
+            return ((ResponseTool)tool).AsAITool();
+        }
+
+        // Strip decoration fields that the Responses API rejects
+        bool modified = false;
+        modified |= obj.Remove("name");
+        modified |= obj.Remove("description");
+
+        if (!modified)
+        {
+            return ((ResponseTool)tool).AsAITool();
+        }
+
+        var sanitizedJson = obj.ToJsonString();
+        var sanitizedTool = ModelReaderWriter.Read<ResponseTool>(BinaryData.FromString(sanitizedJson))!;
+        return sanitizedTool.AsAITool();
+    }
+
+    internal static async Task<ToolboxVersion> GetToolboxVersionAsync(
+        Uri projectEndpoint,
+        AuthenticationTokenProvider credential,
+        string name,
+        string? version,
+        AgentAdministrationClientOptions? clientOptions,
+        CancellationToken cancellationToken)
+    {
+        Throw.IfNull(projectEndpoint);
+        Throw.IfNull(credential);
+        Throw.IfNullOrWhitespace(name);
+
+        var toolboxClient = CreateToolboxClient(projectEndpoint, credential, clientOptions);
+        return await GetToolboxVersionCoreAsync(toolboxClient, name, version, cancellationToken).ConfigureAwait(false);
+    }
+
+    internal static AgentToolboxes CreateToolboxClient(
+        Uri projectEndpoint,
+        AuthenticationTokenProvider credential,
+        AgentAdministrationClientOptions? clientOptions = null)
+    {
+        clientOptions ??= new AgentAdministrationClientOptions();
+        var adminClient = new AgentAdministrationClient(projectEndpoint, credential, clientOptions);
+        return adminClient.GetAgentToolboxes();
+    }
+
+    internal static async Task<ToolboxVersion> GetToolboxVersionCoreAsync(
+        AgentToolboxes toolboxClient,
+        string name,
+        string? version,
+        CancellationToken cancellationToken)
+    {
+        if (version is null)
+        {
+            var record = await toolboxClient.GetToolboxAsync(name, cancellationToken).ConfigureAwait(false);
+            version = record.Value.DefaultVersion
+                ?? throw new InvalidOperationException($"Toolbox '{name}' does not have a default version. Specify an explicit version.");
+        }
+
+        var result = await toolboxClient.GetToolboxVersionAsync(name, version, cancellationToken).ConfigureAwait(false);
+        return result.Value;
+    }
+
+    #endregion
+}

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/HostedAgentUserAgentPolicy.cs

@@ -0,0 +1,84 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Reflection;
+using System.Threading.Tasks;
+
+namespace Microsoft.Agents.AI.Foundry.Hosting;
+
+/// <summary>
+/// Pipeline policy that appends the hosted-agent <c>User-Agent</c> segment
+/// (e.g. <c>"foundry-hosting/agent-framework-dotnet/{version}"</c>) to outgoing requests.
+/// </summary>
+/// <remarks>
+/// <para>
+/// The supplement value is computed once from the Microsoft.Agents.AI.Foundry.Hosting
+/// assembly's informational version. The policy is idempotent on retries: if the segment
+/// is already present in the <c>User-Agent</c> header, the policy does not append it again.
+/// </para>
+/// <para>
+/// This policy is added at request time (per-call <see cref="PipelinePosition"/>)
+/// by <see cref="DelegatingResponsesClient"/> when invoking the wrapped
+/// <see cref="OpenAI.Responses.ResponsesClient"/>. It is only registered when an agent is
+/// resolved by the Foundry hosting layer.
+/// </para>
+/// </remarks>
+internal sealed class HostedAgentUserAgentPolicy : PipelinePolicy
+{
+    public static HostedAgentUserAgentPolicy Instance { get; } = new HostedAgentUserAgentPolicy();
+
+    private static readonly string s_supplementValue = CreateSupplementValue();
+
+    public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+    {
+        AppendHeader(message);
+        ProcessNext(message, pipeline, currentIndex);
+    }
+
+    public override async ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+    {
+        AppendHeader(message);
+        await ProcessNextAsync(message, pipeline, currentIndex).ConfigureAwait(false);
+    }
+
+    private static void AppendHeader(PipelineMessage message)
+    {
+        if (message.Request.Headers.TryGetValue("User-Agent", out var existing) && !string.IsNullOrEmpty(existing))
+        {
+            // Guard against double-append on retries or when the policy
+            // is registered on multiple pipeline positions.
+            if (existing.Contains(s_supplementValue))
+            {
+                return;
+            }
+
+            message.Request.Headers.Set("User-Agent", $"{existing} {s_supplementValue}");
+        }
+        else
+        {
+            message.Request.Headers.Set("User-Agent", s_supplementValue);
+        }
+    }
+
+    private static string CreateSupplementValue()
+    {
+        const string Name = "foundry-hosting/agent-framework-dotnet";
+
+        if (typeof(HostedAgentUserAgentPolicy).Assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>()?.InformationalVersion is string version)
+        {
+            int pos = version.IndexOf('+');
+            if (pos >= 0)
+            {
+                version = version.Substring(0, pos);
+            }
+
+            if (version.Length > 0)
+            {
+                return $"{Name}/{version}";
+            }
+        }
+
+        return Name;
+    }
+}

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/InputConverter.cs

@@ -237,7 +237,7 @@ internal static class InputConverter
         {
             OutputItemMessage msg => ConvertOutputItemMessageToChat(msg),
             OutputItemFunctionToolCall funcCall => ConvertOutputItemFunctionCall(funcCall),
-            FunctionToolCallOutputResource funcOutput => ConvertFunctionToolCallOutputResource(funcOutput),
+            OutputItemFunctionToolCallOutput funcOutput => ConvertFunctionToolCallOutput(funcOutput),
             OutputItemReasoningItem => null,
             _ => null
         };
@@ -332,7 +332,7 @@ internal static class InputConverter
             [new FunctionCallContent(funcCall.CallId, funcCall.Name, arguments)]);
     }
 
-    private static ChatMessage ConvertFunctionToolCallOutputResource(FunctionToolCallOutputResource funcOutput)
+    private static ChatMessage ConvertFunctionToolCallOutput(OutputItemFunctionToolCallOutput funcOutput)
     {
         return new ChatMessage(
             ChatRole.Tool,

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/Microsoft.Agents.AI.Foundry.Hosting.csproj

@@ -34,6 +34,7 @@
     <PackageReference Include="Azure.AI.Projects" VersionOverride="2.1.0-beta.1" />
     <PackageReference Include="Azure.Identity" />
     <PackageReference Include="ModelContextProtocol" />
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" />
   </ItemGroup>
 
   <ItemGroup>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/OutputConverter.cs

@@ -251,16 +251,25 @@ internal static class OutputConverter
         var outputTokens = details.OutputTokenCount ?? 0;
         var totalTokens = details.TotalTokenCount ?? 0;
 
+        var cachedTokens = details.AdditionalCounts?.TryGetValue("InputTokenDetails.CachedTokenCount", out var cached) ?? false
+            ? cached : 0;
+        var reasoningTokens = details.AdditionalCounts?.TryGetValue("OutputTokenDetails.ReasoningTokenCount", out var reasoning) ?? false
+            ? reasoning : 0;
+
         if (existing is not null)
         {
             inputTokens += existing.InputTokens;
             outputTokens += existing.OutputTokens;
             totalTokens += existing.TotalTokens;
+            cachedTokens += existing.InputTokensDetails?.CachedTokens ?? 0;
+            reasoningTokens += existing.OutputTokensDetails?.ReasoningTokens ?? 0;
         }
 
-        return AzureAIAgentServerResponsesModelFactory.ResponseUsage(
+        return new ResponseUsage(
             inputTokens: inputTokens,
+            inputTokensDetails: new ResponseUsageInputTokensDetails(cachedTokens),
             outputTokens: outputTokens,
+            outputTokensDetails: new ResponseUsageOutputTokensDetails(reasoningTokens),
             totalTokens: totalTokens);
     }
 

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/ServiceCollectionExtensions.cs

@@ -3,16 +3,15 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
-using System.Threading.Tasks;
 using Azure.AI.AgentServer.Responses;
 using Azure.Core;
 using Azure.Identity;
-using Microsoft.AspNetCore.Builder;
-using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Routing;
+using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Shared.DiagnosticIds;
+using OpenAI.Responses;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -36,7 +35,7 @@ public static class FoundryHostingExtensions
     /// <para>
     /// Example:
     /// <code>
-    /// builder.AddAIAgent("my-agent", ...);
+    /// builder.Services.AddKeyedSingleton&lt;AIAgent&gt;("my-agent", myAgent);
     /// builder.Services.AddFoundryResponses();
     ///
     /// var app = builder.Build();
@@ -181,13 +180,6 @@ public static class FoundryHostingExtensions
     {
         ArgumentNullException.ThrowIfNull(endpoints);
         endpoints.MapResponsesServer(prefix);
-
-        if (endpoints is IApplicationBuilder app)
-        {
-            // Ensure the middleware is added to the pipeline
-            app.UseMiddleware<AgentFrameworkUserAgentMiddleware>();
-        }
-
         return endpoints;
     }
 
@@ -216,46 +208,85 @@ public static class FoundryHostingExtensions
                     .Build();
     }
 
-    private sealed class AgentFrameworkUserAgentMiddleware(RequestDelegate next)
+    /// <summary>
+    /// Attempts to wrap the agent's underlying <see cref="ResponsesClient"/>
+    /// with a <see cref="DelegatingResponsesClient"/> so every outgoing Responses-API request
+    /// carries the hosted-agent <c>User-Agent</c> segment.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// Best-effort and idempotent. The method is a no-op when:
+    /// <list type="bullet">
+    /// <item><description><paramref name="agent"/> exposes no <see cref="IChatClient"/>;</description></item>
+    /// <item><description>the chat client is not backed by MEAI's internal <c>OpenAIResponsesChatClient</c> (e.g., a non-OpenAI provider or a custom impl);</description></item>
+    /// <item><description>the inner <see cref="ResponsesClient"/> is already a <see cref="DelegatingResponsesClient"/>.</description></item>
+    /// </list>
+    /// </para>
+    /// <para>
+    /// Works for any <see cref="ResponsesClient"/>-derived inner client — both the Foundry-specific
+    /// <see cref="Azure.AI.Extensions.OpenAI.ProjectResponsesClient"/> and the native OpenAI
+    /// <see cref="ResponsesClient"/> obtained from <see cref="OpenAI.OpenAIClient"/>. The wrapper preserves
+    /// the inner client's pipeline (Transport, RetryPolicy, NetworkTimeout, OrganizationId / ProjectId /
+    /// UserAgentApplicationId, custom policies) because every override delegates to the inner instance.
+    /// </para>
+    /// <para>
+    /// Returns the same <paramref name="agent"/> instance unchanged. Mutation happens via
+    /// reflection on MEAI's private <c>_responseClient</c> field; the agent itself is not wrapped.
+    /// </para>
+    /// </remarks>
+    internal static AIAgent TryApplyUserAgent(AIAgent agent)
     {
-        private static readonly string s_userAgentValue = CreateUserAgentValue();
-
-        public async Task InvokeAsync(HttpContext context)
+        var chatClient = agent.GetService<IChatClient>();
+        if (chatClient is null)
         {
-            var headers = context.Request.Headers;
-            var userAgent = headers.UserAgent.ToString();
-
-            if (string.IsNullOrEmpty(userAgent))
-            {
-                headers.UserAgent = s_userAgentValue;
-            }
-            else if (!userAgent.Contains(s_userAgentValue, StringComparison.OrdinalIgnoreCase))
-            {
-                headers.UserAgent = $"{userAgent} {s_userAgentValue}";
-            }
-
-            await next(context).ConfigureAwait(false);
+            return agent;
         }
 
-        private static string CreateUserAgentValue()
+        var meaiType = s_meaiResponsesChatClientType;
+        if (meaiType is null)
         {
-            const string Name = "agent-framework-dotnet";
-
-            if (typeof(AgentFrameworkUserAgentMiddleware).Assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>()?.InformationalVersion is string version)
-            {
-                int pos = version.IndexOf('+');
-                if (pos >= 0)
-                {
-                    version = version.Substring(0, pos);
-                }
-
-                if (version.Length > 0)
-                {
-                    return $"{Name}/{version}";
-                }
-            }
-
-            return Name;
+            return agent;
         }
+
+        var meaiInstance = chatClient.GetService(meaiType);
+        if (meaiInstance is null)
+        {
+            return agent;
+        }
+
+        var field = s_meaiResponseClientField;
+        if (field is null)
+        {
+            return agent;
+        }
+
+        var current = field.GetValue(meaiInstance) as ResponsesClient;
+        if (current is null or DelegatingResponsesClient)
+        {
+            return agent;
+        }
+
+        field.SetValue(meaiInstance, new DelegatingResponsesClient(current));
+        return agent;
     }
+
+    /// <summary>
+    /// MEAI's internal <c>OpenAIResponsesChatClient</c> type, resolved once via reflection.
+    /// <see langword="null"/> if the type cannot be found (e.g., MEAI version drift).
+    /// </summary>
+    [UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",
+        Justification = "MEAI's OpenAIResponsesChatClient is referenced through MicrosoftExtensionsAIResponsesExtensions and survives trimming.")]
+    [UnconditionalSuppressMessage("Trimming", "IL2073:RequiresUnreferencedCode",
+        Justification = "MEAI's OpenAIResponsesChatClient is referenced through MicrosoftExtensionsAIResponsesExtensions and survives trimming.")]
+    private static readonly Type? s_meaiResponsesChatClientType =
+        typeof(MicrosoftExtensionsAIResponsesExtensions).Assembly.GetType("Microsoft.Extensions.AI.OpenAIResponsesChatClient");
+
+    /// <summary>
+    /// MEAI's internal <c>_responseClient</c> field on <c>OpenAIResponsesChatClient</c>,
+    /// resolved once via reflection. <see langword="null"/> if the field cannot be found.
+    /// </summary>
+    [UnconditionalSuppressMessage("Trimming", "IL2080:RequiresDynamicallyAccessedMembers",
+        Justification = "OpenAIResponsesChatClient and its private fields are preserved by the polyfill design; MEAI does the same reflection internally.")]
+    private static readonly FieldInfo? s_meaiResponseClientField =
+        s_meaiResponsesChatClientType?.GetField("_responseClient", BindingFlags.NonPublic | BindingFlags.Instance);
 }

dotnet/src/Microsoft.Agents.AI.Foundry/RequestOptionsExtensions.cs

@@ -3,7 +3,6 @@
 using System.ClientModel.Primitives;
 using System.Collections.Generic;
 using System.Reflection;
-using System.Threading;
 using System.Threading.Tasks;
 
 namespace Microsoft.Agents.AI;
@@ -13,20 +12,6 @@ internal static class RequestOptionsExtensions
     /// <summary>Gets the singleton <see cref="PipelinePolicy"/> that adds a MEAI user-agent header.</summary>
     internal static PipelinePolicy UserAgentPolicy => MeaiUserAgentPolicy.Instance;
 
-    /// <summary>Creates a <see cref="RequestOptions"/> configured for use with Foundry Agents.</summary>
-    public static RequestOptions ToRequestOptions(this CancellationToken cancellationToken, bool streaming)
-    {
-        RequestOptions requestOptions = new()
-        {
-            CancellationToken = cancellationToken,
-            BufferResponse = !streaming
-        };
-
-        requestOptions.AddPolicy(MeaiUserAgentPolicy.Instance, PipelinePosition.PerCall);
-
-        return requestOptions;
-    }
-
     /// <summary>Provides a pipeline policy that adds a "MEAI/x.y.z" user-agent header.</summary>
     private sealed class MeaiUserAgentPolicy : PipelinePolicy
     {

dotnet/src/Microsoft.Agents.AI.Hosting.A2A/A2AAgentHandler.cs

@@ -42,11 +42,19 @@ internal sealed class A2AAgentHandler : IAgentHandler
     /// <inheritdoc/>
     public Task ExecuteAsync(RequestContext context, AgentEventQueue eventQueue, CancellationToken cancellationToken)
     {
+        // Handle task updates
         if (context.IsContinuation)
         {
             return this.HandleTaskUpdateAsync(context, eventQueue, cancellationToken);
         }
 
+        // Handle messages received via streaming endpoint
+        if (context.StreamingResponse)
+        {
+            return this.HandleNewMessageStreamingAsync(context, eventQueue, cancellationToken);
+        }
+
+        // Handle new messages received via non-streaming endpoint
         return this.HandleNewMessageAsync(context, eventQueue, cancellationToken);
     }
 
@@ -80,13 +88,19 @@ internal sealed class A2AAgentHandler : IAgentHandler
             ? new AgentRunOptions { AllowBackgroundResponses = allowBackgroundResponses }
             : new AgentRunOptions { AllowBackgroundResponses = allowBackgroundResponses, AdditionalProperties = context.Metadata.ToAdditionalProperties() };
 
-        var response = await this._hostAgent.RunAsync(
-            chatMessages,
-            session: session,
-            options: options,
-            cancellationToken: cancellationToken).ConfigureAwait(false);
-
-        await this._hostAgent.SaveSessionAsync(contextId, session, cancellationToken).ConfigureAwait(false);
+        AgentResponse response;
+        try
+        {
+            response = await this._hostAgent.RunAsync(
+                chatMessages,
+                session: session,
+                options: options,
+                cancellationToken: cancellationToken).ConfigureAwait(false);
+        }
+        finally
+        {
+            await this._hostAgent.SaveSessionAsync(contextId, session, CancellationToken.None).ConfigureAwait(false);
+        }
 
         if (response.ContinuationToken is null)
         {
@@ -108,6 +122,39 @@ internal sealed class A2AAgentHandler : IAgentHandler
         }
     }
 
+    private async Task HandleNewMessageStreamingAsync(RequestContext context, AgentEventQueue eventQueue, CancellationToken cancellationToken)
+    {
+        var contextId = context.ContextId ?? Guid.NewGuid().ToString("N");
+        var session = await this._hostAgent.GetOrCreateSessionAsync(contextId, cancellationToken).ConfigureAwait(false);
+
+        // AIAgent does not support resuming from arbitrary prior tasks.
+        // Throw explicitly so the client gets a clear error rather than a response
+        // that silently ignores the referenced task context.
+        if (context.Message?.ReferenceTaskIds is { Count: > 0 })
+        {
+            throw new NotSupportedException("ReferenceTaskIds is not supported. AIAgent cannot resume from arbitrary prior task context.");
+        }
+
+        List<ChatMessage> chatMessages = context.Message is not null ? [context.Message.ToChatMessage()] : [];
+
+        var options = context.Metadata is { Count: > 0 }
+            ? new AgentRunOptions { AdditionalProperties = context.Metadata.ToAdditionalProperties() }
+            : null;
+
+        try
+        {
+            await foreach (var update in this._hostAgent.RunStreamingAsync(chatMessages, session, options, cancellationToken).ConfigureAwait(false))
+            {
+                var message = CreateMessageFromUpdate(contextId, update);
+                await eventQueue.EnqueueMessageAsync(message, cancellationToken).ConfigureAwait(false);
+            }
+        }
+        finally
+        {
+            await this._hostAgent.SaveSessionAsync(contextId, session, CancellationToken.None).ConfigureAwait(false);
+        }
+    }
+
     private async Task HandleTaskUpdateAsync(RequestContext context, AgentEventQueue eventQueue, CancellationToken cancellationToken)
     {
         var contextId = context.ContextId ?? Guid.NewGuid().ToString("N");
@@ -141,8 +188,10 @@ internal sealed class A2AAgentHandler : IAgentHandler
             await failUpdater.FailAsync(message: null, CancellationToken.None).ConfigureAwait(false);
             throw;
         }
-
-        await this._hostAgent.SaveSessionAsync(contextId, session, cancellationToken).ConfigureAwait(false);
+        finally
+        {
+            await this._hostAgent.SaveSessionAsync(contextId, session, CancellationToken.None).ConfigureAwait(false);
+        }
 
         if (response.ContinuationToken is null)
         {
@@ -174,6 +223,16 @@ internal sealed class A2AAgentHandler : IAgentHandler
             Metadata = response.AdditionalProperties?.ToA2AMetadata()
         };
 
+    private static Message CreateMessageFromUpdate(string contextId, AgentResponseUpdate update) =>
+        new()
+        {
+            MessageId = update.ResponseId ?? Guid.NewGuid().ToString("N"),
+            ContextId = contextId,
+            Role = Role.Agent,
+            Parts = update.ToParts(),
+            Metadata = update.AdditionalProperties?.ToA2AMetadata()
+        };
+
     private static List<ChatMessage> ExtractChatMessagesFromTaskHistory(AgentTask? agentTask)
     {
         if (agentTask?.History is not { Count: > 0 })

dotnet/src/Microsoft.Agents.AI.Hosting.A2A/Converters/MessageConverter.cs

@@ -8,6 +8,26 @@ namespace Microsoft.Agents.AI.Hosting.A2A.Converters;
 
 internal static class MessageConverter
 {
+    public static List<Part> ToParts(this AgentResponseUpdate update)
+    {
+        if (update is null || update.Contents is not { Count: > 0 })
+        {
+            return [];
+        }
+
+        var parts = new List<Part>();
+        foreach (var content in update.Contents)
+        {
+            var part = content.ToPart();
+            if (part is not null)
+            {
+                parts.Add(part);
+            }
+        }
+
+        return parts;
+    }
+
     public static List<Part> ToParts(this IList<ChatMessage> chatMessages)
     {
         if (chatMessages is null || chatMessages.Count == 0)

dotnet/src/Microsoft.Agents.AI.Hosting.AzureFunctions/BuiltInFunctions.cs

@@ -21,6 +21,8 @@ internal static class BuiltInFunctions
     internal const string HttpPrefix = "http-";
     internal const string McpToolPrefix = "mcptool-";
 
+    private const string WaitForResponseHeaderName = "x-ms-wait-for-response";
+
     internal static readonly string RunAgentHttpFunctionEntryPoint = $"{typeof(BuiltInFunctions).FullName!}.{nameof(RunAgentHttpAsync)}";
     internal static readonly string RunAgentEntityFunctionEntryPoint = $"{typeof(BuiltInFunctions).FullName!}.{nameof(InvokeAgentAsync)}";
     internal static readonly string RunAgentMcpToolFunctionEntryPoint = $"{typeof(BuiltInFunctions).FullName!}.{nameof(RunMcpToolAsync)}";
@@ -62,6 +64,11 @@ internal static class BuiltInFunctions
         StartOrchestrationOptions? options = instanceId is not null ? new StartOrchestrationOptions(instanceId) : null;
         string resolvedInstanceId = await client.ScheduleNewOrchestrationInstanceAsync(orchestrationFunctionName, orchestrationInput, options);
 
+        if (ShouldWaitForResponse(req, defaultValue: false))
+        {
+            return await WaitForWorkflowCompletionAsync(req, client, context, resolvedInstanceId);
+        }
+
         HttpResponseData response = req.CreateResponse(HttpStatusCode.Accepted);
         await response.WriteStringAsync($"Workflow orchestration started for {workflowName}. Orchestration runId: {resolvedInstanceId}");
         return response;
@@ -304,15 +311,7 @@ internal static class BuiltInFunctions
         }
 
         // Check if we should wait for response (default is true)
-        bool waitForResponse = true;
-        if (req.Headers.TryGetValues("x-ms-wait-for-response", out IEnumerable<string>? waitForResponseValues))
-        {
-            string? waitForResponseValue = waitForResponseValues.FirstOrDefault();
-            if (!string.IsNullOrEmpty(waitForResponseValue) && bool.TryParse(waitForResponseValue, out bool parsedValue))
-            {
-                waitForResponse = parsedValue;
-            }
-        }
+        bool waitForResponse = ShouldWaitForResponse(req, defaultValue: true);
 
         AIAgent agentProxy = client.AsDurableAgentProxy(context, agentName);
 
@@ -428,6 +427,95 @@ internal static class BuiltInFunctions
         return metadata.ReadOutputAs<DurableWorkflowResult>()?.Result;
     }
 
+    /// <summary>
+    /// Waits for a workflow orchestration to complete and returns an appropriate HTTP response.
+    /// </summary>
+    private static async Task<HttpResponseData> WaitForWorkflowCompletionAsync(
+        HttpRequestData req,
+        DurableTaskClient client,
+        FunctionContext context,
+        string instanceId)
+    {
+        bool acceptsJson = AcceptsJson(req);
+
+        OrchestrationMetadata? metadata = await client.WaitForInstanceCompletionAsync(
+            instanceId,
+            getInputsAndOutputs: true,
+            cancellation: context.CancellationToken);
+
+        if (metadata is null)
+        {
+            return await CreateErrorResponseAsync(req, context, HttpStatusCode.NotFound,
+                $"No workflow orchestration with ID '{instanceId}' was found.", acceptsJson);
+        }
+
+        if (metadata.RuntimeStatus is OrchestrationRuntimeStatus.Failed)
+        {
+            string errorMessage = metadata.FailureDetails?.ErrorMessage ?? "Unknown error";
+            HttpResponseData failedResponse = req.CreateResponse(HttpStatusCode.OK);
+
+            if (acceptsJson)
+            {
+                await failedResponse.WriteAsJsonAsync(
+                    new WorkflowRunResponse(instanceId, metadata.RuntimeStatus.ToString(), Result: null, Error: errorMessage),
+                    context.CancellationToken);
+            }
+            else
+            {
+                failedResponse.Headers.Add("Content-Type", "text/plain");
+                await failedResponse.WriteStringAsync(errorMessage, context.CancellationToken);
+            }
+
+            return failedResponse;
+        }
+
+        if (metadata.RuntimeStatus is not OrchestrationRuntimeStatus.Completed)
+        {
+            return await CreateErrorResponseAsync(req, context, HttpStatusCode.InternalServerError,
+                $"Workflow orchestration '{instanceId}' ended with unexpected status '{metadata.RuntimeStatus}'.", acceptsJson);
+        }
+
+        string? result = metadata.ReadOutputAs<DurableWorkflowResult>()?.Result;
+
+        HttpResponseData response = req.CreateResponse(HttpStatusCode.OK);
+
+        if (acceptsJson)
+        {
+            JsonElement? resultElement = null;
+            if (!string.IsNullOrEmpty(result))
+            {
+                try
+                {
+                    using JsonDocument doc = JsonDocument.Parse(result);
+                    resultElement = doc.RootElement.Clone();
+                }
+                catch (JsonException)
+                {
+                    // Result is a plain string (not valid JSON) — serialize it as a JSON string element.
+                    var buffer = new System.Buffers.ArrayBufferWriter<byte>();
+                    using (var writer = new Utf8JsonWriter(buffer))
+                    {
+                        writer.WriteStringValue(result);
+                    }
+
+                    using JsonDocument fallbackDoc = JsonDocument.Parse(buffer.WrittenMemory);
+                    resultElement = fallbackDoc.RootElement.Clone();
+                }
+            }
+
+            await response.WriteAsJsonAsync(
+                new WorkflowRunResponse(instanceId, metadata.RuntimeStatus.ToString(), resultElement),
+                context.CancellationToken);
+        }
+        else
+        {
+            response.Headers.Add("Content-Type", "text/plain");
+            await response.WriteStringAsync(result ?? string.Empty, context.CancellationToken);
+        }
+
+        return response;
+    }
+
     /// <summary>
     /// Creates an error response with the specified status code and error message.
     /// </summary>
@@ -435,18 +523,18 @@ internal static class BuiltInFunctions
     /// <param name="context">The function context.</param>
     /// <param name="statusCode">The HTTP status code.</param>
     /// <param name="errorMessage">The error message.</param>
+    /// <param name="acceptsJson">Optional pre-computed value indicating whether the client accepts JSON. When <see langword="null"/>, the value is determined from the request's <c>Accept</c> header.</param>
     /// <returns>The HTTP response data containing the error.</returns>
     private static async Task<HttpResponseData> CreateErrorResponseAsync(
         HttpRequestData req,
         FunctionContext context,
         HttpStatusCode statusCode,
-        string errorMessage)
+        string errorMessage,
+        bool? acceptsJson = null)
     {
         HttpResponseData response = req.CreateResponse(statusCode);
-        bool acceptsJson = req.Headers.TryGetValues("Accept", out IEnumerable<string>? acceptValues) &&
-            acceptValues.Contains("application/json", StringComparer.OrdinalIgnoreCase);
 
-        if (acceptsJson)
+        if (acceptsJson ?? AcceptsJson(req))
         {
             ErrorResponse errorResponse = new((int)statusCode, errorMessage);
             await response.WriteAsJsonAsync(errorResponse, context.CancellationToken);
@@ -479,10 +567,7 @@ internal static class BuiltInFunctions
         HttpResponseData response = req.CreateResponse(statusCode);
         response.Headers.Add("x-ms-thread-id", sessionId);
 
-        bool acceptsJson = req.Headers.TryGetValues("Accept", out IEnumerable<string>? acceptValues) &&
-            acceptValues.Contains("application/json", StringComparer.OrdinalIgnoreCase);
-
-        if (acceptsJson)
+        if (AcceptsJson(req))
         {
             AgentRunSuccessResponse successResponse = new((int)statusCode, sessionId, agentResponse);
             await response.WriteAsJsonAsync(successResponse, context.CancellationToken);
@@ -511,10 +596,7 @@ internal static class BuiltInFunctions
         HttpResponseData response = req.CreateResponse(HttpStatusCode.Accepted);
         response.Headers.Add("x-ms-thread-id", sessionId);
 
-        bool acceptsJson = req.Headers.TryGetValues("Accept", out IEnumerable<string>? acceptValues) &&
-            acceptValues.Contains("application/json", StringComparer.OrdinalIgnoreCase);
-
-        if (acceptsJson)
+        if (AcceptsJson(req))
         {
             AgentRunAcceptedResponse acceptedResponse = new((int)HttpStatusCode.Accepted, sessionId);
             await response.WriteAsJsonAsync(acceptedResponse, context.CancellationToken);
@@ -528,6 +610,34 @@ internal static class BuiltInFunctions
         return response;
     }
 
+    /// <summary>
+    /// Returns <see langword="true"/> when the caller has requested waiting for the workflow/agent to complete,
+    /// as indicated by the <c>x-ms-wait-for-response</c> header. Falls back to <paramref name="defaultValue"/>
+    /// when the header is absent or not a valid boolean.
+    /// </summary>
+    private static bool ShouldWaitForResponse(HttpRequestData req, bool defaultValue)
+    {
+        if (req.Headers.TryGetValues(WaitForResponseHeaderName, out IEnumerable<string>? values) &&
+            bool.TryParse(values.FirstOrDefault(), out bool parsed))
+        {
+            return parsed;
+        }
+
+        return defaultValue;
+    }
+
+    /// <summary>
+    /// Returns <see langword="true"/> when the request accepts the <c>application/json</c> media type.
+    /// </summary>
+    private static bool AcceptsJson(HttpRequestData req)
+    {
+        return req.Headers.TryGetValues("Accept", out IEnumerable<string>? acceptValues) &&
+            acceptValues
+                .SelectMany(v => v.Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
+                .Select(v => v.Split(';', 2)[0].Trim())
+                .Contains("application/json", StringComparer.OrdinalIgnoreCase);
+    }
+
     private static string GetAgentName(FunctionContext context)
     {
         // Check if the function name starts with the HttpPrefix
@@ -591,6 +701,19 @@ internal static class BuiltInFunctions
         [property: JsonPropertyName("eventName")] string? EventName,
         [property: JsonPropertyName("response")] JsonElement Response);
 
+    /// <summary>
+    /// Represents a workflow run response when waiting for completion.
+    /// </summary>
+    /// <param name="RunId">The orchestration run ID.</param>
+    /// <param name="WorkflowStatus">The orchestration runtime status (e.g., "Completed", "Failed").</param>
+    /// <param name="Result">The workflow result as a JSON element so POCOs serialize as nested objects rather than escaped strings.</param>
+    /// <param name="Error">An optional error message when the workflow has failed.</param>
+    private sealed record WorkflowRunResponse(
+        [property: JsonPropertyName("runId")] string RunId,
+        [property: JsonPropertyName("workflowStatus")] string WorkflowStatus,
+        [property: JsonPropertyName("result")] JsonElement? Result,
+        [property: JsonPropertyName("error"), JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)] string? Error = null);
+
     /// <summary>
     /// A service provider that combines the original service provider with an additional DurableTaskClient instance.
     /// </summary>

dotnet/src/Microsoft.Agents.AI.Hosting.AzureFunctions/CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [Unreleased]
 
+- Support returning workflow results from HTTP trigger endpoint ([#5321](https://github.com/microsoft/agent-framework/pull/5321))
 - Added MCP tool trigger support for durable workflows ([#4768](https://github.com/microsoft/agent-framework/pull/4768))
 - Added Azure Functions hosting support for durable workflows ([#4436](https://github.com/microsoft/agent-framework/pull/4436))
 

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/DeclarativeWorkflowOptions.cs

@@ -26,6 +26,12 @@ public sealed class DeclarativeWorkflowOptions(ResponseAgentProvider agentProvid
     /// </summary>
     public IMcpToolHandler? McpToolHandler { get; init; }
 
+    /// <summary>
+    /// Gets or sets the HTTP request handler for executing <c>HttpRequestAction</c> actions within workflows.
+    /// If not set, HTTP request actions will fail with an appropriate error message.
+    /// </summary>
+    public IHttpRequestHandler? HttpRequestHandler { get; init; }
+
     /// <summary>
     /// Defines the configuration settings for the workflow.
     /// </summary>

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/DefaultHttpRequestHandler.cs

@@ -0,0 +1,289 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative;
+
+/// <summary>
+/// Default implementation of <see cref="IHttpRequestHandler"/> built on <see cref="HttpClient"/>.
+/// </summary>
+/// <remarks>
+/// <para>
+/// This handler supports per-request authentication via an optional <c>httpClientProvider</c> callback that
+/// returns a pre-configured <see cref="HttpClient"/> for a given request (e.g. authenticated, custom handler).
+/// When the provider returns <see langword="null"/>, or no provider is supplied, a shared internal <see cref="HttpClient"/>
+/// is used.
+/// </para>
+/// <para>
+/// The handler applies the per-request <see cref="HttpRequestInfo.Timeout"/> using a linked <see cref="CancellationTokenSource"/>
+/// so it does not mutate <see cref="HttpClient.Timeout"/> on shared instances.
+/// </para>
+/// </remarks>
+public sealed class DefaultHttpRequestHandler : IHttpRequestHandler, IAsyncDisposable
+{
+    private readonly Func<HttpRequestInfo, CancellationToken, Task<HttpClient?>>? _httpClientProvider;
+    private readonly Lazy<HttpClient> _ownedHttpClient;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DefaultHttpRequestHandler"/> class that uses an
+    /// internally owned <see cref="HttpClient"/> for all requests. The internal client is disposed
+    /// when <see cref="DisposeAsync"/> is called.
+    /// </summary>
+    public DefaultHttpRequestHandler()
+        : this(httpClientProvider: null)
+    {
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DefaultHttpRequestHandler"/> class that uses the
+    /// supplied <see cref="HttpClient"/> for all requests.
+    /// </summary>
+    /// <param name="httpClient">
+    /// The <see cref="HttpClient"/> to use for all requests. The caller retains ownership of this
+    /// instance; it is not disposed by <see cref="DisposeAsync"/>.
+    /// </param>
+    /// <exception cref="ArgumentNullException"><paramref name="httpClient"/> is <see langword="null"/>.</exception>
+    public DefaultHttpRequestHandler(HttpClient httpClient)
+        : this(CreateSingleClientProvider(httpClient))
+    {
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DefaultHttpRequestHandler"/> class that selects
+    /// an <see cref="HttpClient"/> per request via a caller-supplied callback — for example, to route
+    /// different URLs through differently authenticated clients.
+    /// </summary>
+    /// <param name="httpClientProvider">
+    /// An optional callback invoked for each request. The callback receives the <see cref="HttpRequestInfo"/>
+    /// and should return a pre-configured <see cref="HttpClient"/> (e.g. with authentication or a custom
+    /// transport). Return <see langword="null"/> to fall back to the handler's shared internal
+    /// <see cref="HttpClient"/>.
+    /// </param>
+    /// <remarks>
+    /// <para>
+    /// <b>Ownership</b>: the caller is solely responsible for the lifetime of clients returned by this
+    /// callback. <see cref="DefaultHttpRequestHandler"/> will <b>not</b> dispose provider-returned
+    /// clients; only the handler's internally owned fallback client is disposed by <see cref="DisposeAsync"/>.
+    /// </para>
+    /// <para>
+    /// <b>Reuse</b>: callers are expected to cache and reuse clients (for example, keyed by base URL or
+    /// auth scope) across requests. Returning a newly allocated <see cref="HttpClient"/> on every
+    /// invocation will leak sockets and handler resources.
+    /// </para>
+    /// </remarks>
+    public DefaultHttpRequestHandler(Func<HttpRequestInfo, CancellationToken, Task<HttpClient?>>? httpClientProvider)
+    {
+        this._httpClientProvider = httpClientProvider;
+        this._ownedHttpClient = new Lazy<HttpClient>(() => new HttpClient(), LazyThreadSafetyMode.ExecutionAndPublication);
+    }
+
+    private static Func<HttpRequestInfo, CancellationToken, Task<HttpClient?>> CreateSingleClientProvider(HttpClient httpClient)
+    {
+        if (httpClient is null)
+        {
+            throw new ArgumentNullException(nameof(httpClient));
+        }
+
+        return (_, _) => Task.FromResult<HttpClient?>(httpClient);
+    }
+
+    /// <inheritdoc/>
+    public async Task<HttpRequestResult> SendAsync(HttpRequestInfo request, CancellationToken cancellationToken = default)
+    {
+        if (request is null)
+        {
+            throw new ArgumentNullException(nameof(request));
+        }
+
+        if (string.IsNullOrWhiteSpace(request.Url))
+        {
+            throw new ArgumentException("Request URL must be provided.", nameof(request));
+        }
+
+        if (string.IsNullOrWhiteSpace(request.Method))
+        {
+            throw new ArgumentException("Request method must be provided.", nameof(request));
+        }
+
+        HttpClient? providedClient = null;
+        if (this._httpClientProvider is not null)
+        {
+            providedClient = await this._httpClientProvider(request, cancellationToken).ConfigureAwait(false);
+        }
+
+        HttpClient client = providedClient ?? this._ownedHttpClient.Value;
+
+        using HttpRequestMessage httpRequest = BuildHttpRequestMessage(request);
+
+        using CancellationTokenSource? timeoutCts = request.Timeout is { } timeout && timeout > TimeSpan.Zero
+            ? CancellationTokenSource.CreateLinkedTokenSource(cancellationToken)
+            : null;
+
+        timeoutCts?.CancelAfter(request.Timeout!.Value);
+
+        CancellationToken effectiveToken = timeoutCts?.Token ?? cancellationToken;
+
+        using HttpResponseMessage httpResponse = await client
+            .SendAsync(httpRequest, HttpCompletionOption.ResponseContentRead, effectiveToken)
+            .ConfigureAwait(false);
+
+        string? body = httpResponse.Content is null
+            ? null
+#if NET
+            : await httpResponse.Content.ReadAsStringAsync(effectiveToken).ConfigureAwait(false);
+#else
+            : await httpResponse.Content.ReadAsStringAsync().ConfigureAwait(false);
+#endif
+
+        Dictionary<string, IReadOnlyList<string>> headers = new(StringComparer.OrdinalIgnoreCase);
+        AppendHeaders(headers, httpResponse.Headers);
+        if (httpResponse.Content is not null)
+        {
+            AppendHeaders(headers, httpResponse.Content.Headers);
+        }
+
+        return new HttpRequestResult
+        {
+            StatusCode = (int)httpResponse.StatusCode,
+            IsSuccessStatusCode = httpResponse.IsSuccessStatusCode,
+            Body = body,
+            Headers = headers,
+        };
+    }
+
+    /// <inheritdoc/>
+    public ValueTask DisposeAsync()
+    {
+        if (this._ownedHttpClient.IsValueCreated)
+        {
+            this._ownedHttpClient.Value.Dispose();
+        }
+
+        return default;
+    }
+
+    private static HttpRequestMessage BuildHttpRequestMessage(HttpRequestInfo request)
+    {
+        HttpMethod method = ResolveMethod(request.Method);
+        string requestUri = ResolveRequestUri(request);
+        HttpRequestMessage httpRequest = new(method, requestUri);
+
+        if (request.Body is not null)
+        {
+            string contentType = string.IsNullOrWhiteSpace(request.BodyContentType)
+                ? "text/plain"
+                : request.BodyContentType!;
+
+            httpRequest.Content = new StringContent(request.Body, Encoding.UTF8);
+            // Replace the default content-type header (including charset) with the declared type.
+            httpRequest.Content.Headers.Remove("Content-Type");
+            httpRequest.Content.Headers.TryAddWithoutValidation("Content-Type", contentType);
+        }
+
+        if (request.Headers is not null)
+        {
+            foreach (KeyValuePair<string, string> header in request.Headers)
+            {
+                if (string.IsNullOrEmpty(header.Key))
+                {
+                    continue;
+                }
+
+                // Content-* headers belong on HttpContent; all others belong on the request.
+                if (header.Key.StartsWith("Content-", StringComparison.OrdinalIgnoreCase) && httpRequest.Content is not null)
+                {
+                    httpRequest.Content.Headers.Remove(header.Key);
+                    httpRequest.Content.Headers.TryAddWithoutValidation(header.Key, header.Value);
+                    continue;
+                }
+
+                if (!httpRequest.Headers.TryAddWithoutValidation(header.Key, header.Value))
+                {
+                    httpRequest.Content?.Headers.TryAddWithoutValidation(header.Key, header.Value);
+                }
+            }
+        }
+
+        return httpRequest;
+    }
+
+    private static HttpMethod ResolveMethod(string method)
+    {
+        string normalized = method.Trim().ToUpperInvariant();
+        return normalized switch
+        {
+            "GET" => HttpMethod.Get,
+            "POST" => HttpMethod.Post,
+            "PUT" => HttpMethod.Put,
+            "DELETE" => HttpMethod.Delete,
+#if NET
+            "PATCH" => HttpMethod.Patch,
+#else
+            "PATCH" => new HttpMethod("PATCH"),
+#endif
+            _ => new HttpMethod(normalized),
+        };
+    }
+
+    private static string ResolveRequestUri(HttpRequestInfo request)
+    {
+        string baseUrl = request.Url;
+        if (request.QueryParameters is null || request.QueryParameters.Count == 0)
+        {
+            return baseUrl;
+        }
+
+        StringBuilder queryBuilder = new();
+        foreach (KeyValuePair<string, string> parameter in request.QueryParameters)
+        {
+            if (string.IsNullOrEmpty(parameter.Key))
+            {
+                continue;
+            }
+
+            if (queryBuilder.Length > 0)
+            {
+                queryBuilder.Append('&');
+            }
+
+            queryBuilder.Append(Uri.EscapeDataString(parameter.Key))
+                .Append('=')
+                .Append(Uri.EscapeDataString(parameter.Value ?? string.Empty));
+        }
+
+        if (queryBuilder.Length == 0)
+        {
+            return baseUrl;
+        }
+
+        char separator = baseUrl.Contains('?') ? '&' : '?';
+        return string.Concat(baseUrl, separator.ToString(), queryBuilder.ToString());
+    }
+
+    private static void AppendHeaders(
+        Dictionary<string, IReadOnlyList<string>> target,
+        System.Net.Http.Headers.HttpHeaders source)
+    {
+        foreach (KeyValuePair<string, IEnumerable<string>> header in source)
+        {
+            string[] values = header.Value.ToArray();
+
+            if (target.TryGetValue(header.Key, out IReadOnlyList<string>? existing))
+            {
+                List<string> combined = new(existing);
+                combined.AddRange(values);
+                target[header.Key] = combined;
+            }
+            else
+            {
+                target[header.Key] = values;
+            }
+        }
+    }
+}

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Extensions/ChatMessageExtensions.cs

@@ -16,6 +16,60 @@ internal static class ChatMessageExtensions
     public static RecordValue ToRecord(this ChatMessage message) =>
         FormulaValue.NewRecordFromFields(message.GetMessageFields());
 
+    /// <summary>
+    /// Merges the user-authored <paramref name="input"/> with the round-tripped
+    /// <paramref name="inputMessage"/> returned by <c>AgentProvider.CreateMessageAsync</c>
+    /// to produce the value stored in <c>System.LastMessage</c>.
+    /// </summary>
+    /// <remarks>
+    /// The agent service often strips or alters <see cref="TextContent"/> on round-trip,
+    /// while replacing inline media (<see cref="DataContent"/>, <see cref="UriContent"/>)
+    /// with server-side references (typically <see cref="HostedFileContent"/>).
+    /// We want both: the original text (so <c>=System.LastMessage.Text</c> works) and
+    /// the server's media references (so subsequent actions don't re-upload large blobs).
+    /// <para>
+    /// Strategy: keep <paramref name="inputMessage"/> as the base — it has the server-generated
+    /// <see cref="ChatMessage.MessageId"/> and any provider-augmented metadata, and is forward-
+    /// compatible with new properties added on <see cref="ChatMessage"/> in the abstractions
+    /// layer. Only the <see cref="ChatMessage.Contents"/> list is mutated to substitute
+    /// original <see cref="TextContent"/> items in place (and append any extras the round-trip
+    /// dropped). Non-text content items returned by the service are left untouched so
+    /// server-side references survive.
+    /// </para>
+    /// </remarks>
+    public static ChatMessage MergeForLastMessage(this ChatMessage input, ChatMessage? inputMessage)
+    {
+        if (inputMessage is null)
+        {
+            return input;
+        }
+
+        // Build a queue of the original text items, in order. Fall back to ChatMessage.Text
+        // if the input has no explicit TextContent entries.
+        Queue<TextContent> originalTexts = new(input.Contents.OfType<TextContent>());
+        if (originalTexts.Count == 0 && !string.IsNullOrEmpty(input.Text))
+        {
+            originalTexts.Enqueue(new TextContent(input.Text));
+        }
+
+        // Replace TextContent items in inputMessage.Contents with the originals, in order.
+        for (int i = 0; i < inputMessage.Contents.Count && originalTexts.Count > 0; i++)
+        {
+            if (inputMessage.Contents[i] is TextContent)
+            {
+                inputMessage.Contents[i] = originalTexts.Dequeue();
+            }
+        }
+
+        // Append any remaining original text items that the round-trip dropped entirely.
+        while (originalTexts.Count > 0)
+        {
+            inputMessage.Contents.Add(originalTexts.Dequeue());
+        }
+
+        return inputMessage;
+    }
+
     public static TableValue ToTable(this IEnumerable<ChatMessage> messages) =>
         FormulaValue.NewTable(TypeSchema.Message.RecordType, messages.Select(message => message.ToRecord()));
 

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/IHttpRequestHandler.cs

@@ -0,0 +1,103 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative;
+
+/// <summary>
+/// Defines the contract for executing HTTP requests emitted by <c>HttpRequestAction</c> within declarative workflows.
+/// </summary>
+/// <remarks>
+/// This interface allows the HTTP request dispatch to be abstracted, enabling different implementations
+/// for local development, hosted workflows, authenticated scenarios, and testing.
+/// </remarks>
+public interface IHttpRequestHandler
+{
+    /// <summary>
+    /// Sends an HTTP request and returns the response.
+    /// </summary>
+    /// <param name="request">The HTTP request to send.</param>
+    /// <param name="cancellationToken">A token to observe cancellation.</param>
+    /// <returns>The <see cref="HttpRequestResult"/> describing the HTTP response.</returns>
+    Task<HttpRequestResult> SendAsync(
+        HttpRequestInfo request,
+        CancellationToken cancellationToken = default);
+}
+
+/// <summary>
+/// Describes an HTTP request to be sent by an <see cref="IHttpRequestHandler"/>.
+/// </summary>
+[SuppressMessage("Design", "CA1056:URI-like properties should not be strings", Justification = "URL is carried as a string to preserve the declarative expression result and to avoid forcing handler implementations to construct a Uri eagerly.")]
+public sealed class HttpRequestInfo
+{
+    /// <summary>
+    /// Gets the HTTP method to use (GET, POST, PUT, PATCH, DELETE).
+    /// </summary>
+    public string Method { get; init; } = "GET";
+
+    /// <summary>
+    /// Gets the absolute URL to send the request to.
+    /// </summary>
+    public string Url { get; init; } = string.Empty;
+
+    /// <summary>
+    /// Gets the headers to include on the request, excluding the <c>Content-Type</c> header (which is supplied via <see cref="BodyContentType"/>).
+    /// </summary>
+    public IReadOnlyDictionary<string, string>? Headers { get; init; }
+
+    /// <summary>
+    /// Gets the <c>Content-Type</c> of the request body, or <see langword="null"/> if no body is sent.
+    /// </summary>
+    public string? BodyContentType { get; init; }
+
+    /// <summary>
+    /// Gets the serialized request body, or <see langword="null"/> if no body is sent.
+    /// </summary>
+    public string? Body { get; init; }
+
+    /// <summary>
+    /// Gets the maximum amount of time to wait for the request to complete, or <see langword="null"/> to use the handler default.
+    /// </summary>
+    public TimeSpan? Timeout { get; init; }
+
+    /// <summary>
+    /// Gets the query parameters to append to the request URL, with values already formatted as strings.
+    /// </summary>
+    public IReadOnlyDictionary<string, string>? QueryParameters { get; init; }
+
+    /// <summary>
+    /// Gets the name of the declared remote connection, or <see langword="null"/> if no connection is declared.
+    /// This maps to the Foundry project connection Id and is only used when running in foundry service.
+    /// </summary>
+    public string? ConnectionName { get; init; }
+}
+
+/// <summary>
+/// Represents the result of an HTTP request executed by an <see cref="IHttpRequestHandler"/>.
+/// </summary>
+public sealed class HttpRequestResult
+{
+    /// <summary>
+    /// Gets the HTTP status code returned by the server.
+    /// </summary>
+    public int StatusCode { get; init; }
+
+    /// <summary>
+    /// Gets a value indicating whether the status code is in the range 200-299.
+    /// </summary>
+    public bool IsSuccessStatusCode { get; init; }
+
+    /// <summary>
+    /// Gets the response body, or <see langword="null"/> if no body was returned.
+    /// </summary>
+    public string? Body { get; init; }
+
+    /// <summary>
+    /// Gets the response headers keyed by header name. Each header may have multiple values.
+    /// </summary>
+    public IReadOnlyDictionary<string, IReadOnlyList<string>>? Headers { get; init; }
+}

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Interpreter/DeclarativeWorkflowExecutor.cs

@@ -43,7 +43,11 @@ internal sealed class DeclarativeWorkflowExecutor<TInput>(
         await declarativeContext.QueueConversationUpdateAsync(conversationId, isExternal: true, cancellationToken).ConfigureAwait(false);
 
         ChatMessage inputMessage = await options.AgentProvider.CreateMessageAsync(conversationId, input, cancellationToken).ConfigureAwait(false);
-        await declarativeContext.SetLastMessageAsync(inputMessage).ConfigureAwait(false);
+
+        // Use the original input for System.LastMessage to ensure Text is preserved (the
+        // service may strip text on round-trip), but substitute server-side media references
+        // (e.g., HostedFileContent) so subsequent actions don't re-upload large blobs.
+        await declarativeContext.SetLastMessageAsync(input.MergeForLastMessage(inputMessage)).ConfigureAwait(false);
 
         await context.SendResultMessageAsync(this.Id, cancellationToken).ConfigureAwait(false);
     }

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Interpreter/WorkflowActionVisitor.cs

@@ -529,6 +529,18 @@ internal sealed class WorkflowActionVisitor : DialogActionVisitor
         this._workflowModel.AddNode(new DelegateActionExecutor(postId, this._workflowState, action.CompleteAsync), action.ParentId);
     }
 
+    protected override void Visit(HttpRequestAction item)
+    {
+        this.Trace(item);
+
+        if (this._workflowOptions.HttpRequestHandler is null)
+        {
+            throw new DeclarativeModelException("HTTP request handler not configured. Set HttpRequestHandler in DeclarativeWorkflowOptions to use HttpRequestAction actions.");
+        }
+
+        this.ContinueWith(new HttpRequestExecutor(item, this._workflowOptions.HttpRequestHandler, this._workflowOptions.AgentProvider, this._workflowState));
+    }
+
     #region Not supported
 
     protected override void Visit(AnswerQuestionWithAI item) => this.NotSupported(item);
@@ -573,8 +585,6 @@ internal sealed class WorkflowActionVisitor : DialogActionVisitor
 
     protected override void Visit(GetConversationMembers item) => this.NotSupported(item);
 
-    protected override void Visit(HttpRequestAction item) => this.NotSupported(item);
-
     protected override void Visit(RecognizeIntent item) => this.NotSupported(item);
 
     protected override void Visit(TransferConversation item) => this.NotSupported(item);

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Kit/RootExecutor.cs

@@ -58,7 +58,6 @@ public abstract class RootExecutor<TInput> : Executor<TInput>, IResettableExecut
     public override async ValueTask HandleAsync(TInput message, IWorkflowContext context, CancellationToken cancellationToken)
     {
         DeclarativeWorkflowContext declarativeContext = new(context, this._state);
-        await this.ExecuteAsync(message, declarativeContext, cancellationToken).ConfigureAwait(false);
 
         ChatMessage input = (this._inputTransform ?? DefaultInputTransform).Invoke(message);
 
@@ -69,7 +68,13 @@ public abstract class RootExecutor<TInput> : Executor<TInput>, IResettableExecut
         await declarativeContext.QueueConversationUpdateAsync(this._conversationId, isExternal: true, cancellationToken).ConfigureAwait(false);
 
         ChatMessage inputMessage = await this._agentProvider.CreateMessageAsync(this._conversationId, input, cancellationToken).ConfigureAwait(false);
-        await declarativeContext.SetLastMessageAsync(inputMessage).ConfigureAwait(false);
+
+        // Use the original input for System.LastMessage to ensure Text is preserved (the
+        // service may strip text on round-trip), but substitute server-side media references
+        // (e.g., HostedFileContent) so subsequent actions don't re-upload large blobs.
+        await declarativeContext.SetLastMessageAsync(input.MergeForLastMessage(inputMessage)).ConfigureAwait(false);
+
+        await this.ExecuteAsync(message, declarativeContext, cancellationToken).ConfigureAwait(false);
 
         await declarativeContext.SendResultMessageAsync(this.Id, cancellationToken).ConfigureAwait(false);
     }

dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/ObjectModel/HttpRequestExecutor.cs

@@ -0,0 +1,346 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Text.Json;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Agents.AI.Workflows.Declarative.Extensions;
+using Microsoft.Agents.AI.Workflows.Declarative.Interpreter;
+using Microsoft.Agents.AI.Workflows.Declarative.Kit;
+using Microsoft.Agents.AI.Workflows.Declarative.PowerFx;
+using Microsoft.Agents.ObjectModel;
+using Microsoft.Extensions.AI;
+using Microsoft.PowerFx.Types;
+using Microsoft.Shared.Diagnostics;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative.ObjectModel;
+
+/// <summary>
+/// Executor for the <see cref="HttpRequestAction"/> action.
+/// Dispatches the request through the configured <see cref="IHttpRequestHandler"/> and assigns
+/// the response body and headers to the declared property paths.
+/// </summary>
+internal sealed class HttpRequestExecutor(
+    HttpRequestAction model,
+    IHttpRequestHandler httpRequestHandler,
+    ResponseAgentProvider agentProvider,
+    WorkflowFormulaState state) :
+    DeclarativeActionExecutor<HttpRequestAction>(model, state)
+{
+    /// <inheritdoc/>
+    protected override async ValueTask<object?> ExecuteAsync(IWorkflowContext context, CancellationToken cancellationToken = default)
+    {
+        string method = this.GetMethod();
+        string url = this.GetUrl();
+        Dictionary<string, string>? headers = this.GetHeaders();
+        Dictionary<string, string>? queryParameters = this.GetQueryParameters();
+        (string? body, string? contentType) = this.GetBody();
+        TimeSpan? timeout = this.GetTimeout();
+        string? conversationId = this.GetConversationId();
+        string? connectionName = this.GetConnectionName();
+
+        HttpRequestInfo requestInfo = new()
+        {
+            Method = method,
+            Url = url,
+            Headers = headers,
+            QueryParameters = queryParameters,
+            Body = body,
+            BodyContentType = contentType,
+            Timeout = timeout,
+            ConnectionName = connectionName,
+        };
+
+        HttpRequestResult result;
+        try
+        {
+            result = await httpRequestHandler.SendAsync(requestInfo, cancellationToken).ConfigureAwait(false);
+        }
+        catch (OperationCanceledException) when (!cancellationToken.IsCancellationRequested)
+        {
+            throw this.Exception($"HTTP request to '{url}' timed out.");
+        }
+        catch (Exception exception) when (exception is not DeclarativeActionException)
+        {
+            throw this.Exception($"HTTP request to '{url}' failed: {exception.Message}", exception);
+        }
+
+        if (result.IsSuccessStatusCode)
+        {
+            await this.AssignResponseAsync(context, result.Body).ConfigureAwait(false);
+            await this.AssignResponseHeadersAsync(context, result.Headers).ConfigureAwait(false);
+            await this.AddResponseToConversationAsync(conversationId, result.Body, cancellationToken).ConfigureAwait(false);
+            return default;
+        }
+
+        // Non-success status code - throw.
+        // Also publish response headers for diagnostic purposes.
+        await this.AssignResponseHeadersAsync(context, result.Headers).ConfigureAwait(false);
+
+        string bodyPreview = FormatBodyForDiagnostics(result.Body);
+        string message = bodyPreview.Length == 0
+            ? $"HTTP request to '{url}' failed with status code {result.StatusCode}."
+            : $"HTTP request to '{url}' failed with status code {result.StatusCode}. Body: '{bodyPreview}'";
+
+        throw this.Exception(message);
+    }
+
+    // Response bodies can echo secrets (tokens, PII) and may be very large (multi-MB HTML error pages).
+    // Exception messages are often logged and persisted, so we clip the body to bound both exposure
+    // and message size. Full bodies are still available via the success path (assigned to Response).
+    private const int MaxBodyDiagnosticLength = 256;
+    private const string BodyTruncationSuffix = " \u2026 [truncated]";
+
+    private static string FormatBodyForDiagnostics(string? body)
+    {
+        if (string.IsNullOrEmpty(body))
+        {
+            return string.Empty;
+        }
+
+        int sourceLen = body!.Length;
+        bool truncated = sourceLen > MaxBodyDiagnosticLength;
+        int copyLen = truncated ? MaxBodyDiagnosticLength : sourceLen;
+        int finalLen = copyLen + (truncated ? BodyTruncationSuffix.Length : 0);
+
+        // Size the buffer for the final string so we only allocate once for the chars
+        // and once for the string itself. For a 10 KB error body we touch 256 chars instead of 10,000.
+        char[] buffer = new char[finalLen];
+        for (int i = 0; i < copyLen; i++)
+        {
+            char c = body[i];
+            buffer[i] = c is '\r' or '\n' or '\t' ? ' ' : c;
+        }
+
+        if (truncated)
+        {
+            BodyTruncationSuffix.CopyTo(0, buffer, copyLen, BodyTruncationSuffix.Length);
+        }
+
+        return new string(buffer);
+    }
+
+    private async ValueTask AddResponseToConversationAsync(string? conversationId, string? responseBody, CancellationToken cancellationToken)
+    {
+        if (conversationId is null || string.IsNullOrEmpty(responseBody))
+        {
+            return;
+        }
+
+        ChatMessage message = new(ChatRole.Assistant, responseBody);
+        await agentProvider.CreateMessageAsync(conversationId, message, cancellationToken).ConfigureAwait(false);
+    }
+
+    private async ValueTask AssignResponseAsync(IWorkflowContext context, string? responseBody)
+    {
+        if (this.Model.Response is not { Path: { } responsePath })
+        {
+            return;
+        }
+
+        await this.AssignAsync(responsePath, ParseResponseBody(responseBody), context).ConfigureAwait(false);
+    }
+
+    private async ValueTask AssignResponseHeadersAsync(IWorkflowContext context, IReadOnlyDictionary<string, IReadOnlyList<string>>? responseHeaders)
+    {
+        if (this.Model.ResponseHeaders is not { Path: { } headersPath })
+        {
+            return;
+        }
+
+        if (responseHeaders is null || responseHeaders.Count == 0)
+        {
+            await this.AssignAsync(headersPath, FormulaValue.NewBlank(), context).ConfigureAwait(false);
+            return;
+        }
+
+        // Flatten multi-value headers by joining with commas (standard HTTP header folding).
+        Dictionary<string, object?> flattened = new(StringComparer.OrdinalIgnoreCase);
+        foreach (KeyValuePair<string, IReadOnlyList<string>> header in responseHeaders)
+        {
+            flattened[header.Key] = string.Join(",", header.Value);
+        }
+
+        await this.AssignAsync(headersPath, flattened.ToFormula(), context).ConfigureAwait(false);
+    }
+
+    private static FormulaValue ParseResponseBody(string? responseBody)
+    {
+        if (string.IsNullOrEmpty(responseBody))
+        {
+            return FormulaValue.NewBlank();
+        }
+
+        // Attempt to parse as JSON so records/tables are exposed naturally to the workflow.
+        try
+        {
+            using JsonDocument jsonDocument = JsonDocument.Parse(responseBody);
+
+            object? parsedValue = jsonDocument.RootElement.ValueKind switch
+            {
+                JsonValueKind.Object => jsonDocument.ParseRecord(VariableType.RecordType),
+                JsonValueKind.Array => jsonDocument.ParseList(jsonDocument.RootElement.GetListTypeFromJson()),
+                JsonValueKind.String => jsonDocument.RootElement.GetString(),
+                JsonValueKind.Number => jsonDocument.RootElement.TryGetInt64(out long l)
+                    ? l
+                    : jsonDocument.RootElement.GetDouble(),
+                JsonValueKind.True => true,
+                JsonValueKind.False => false,
+                JsonValueKind.Null => null,
+                _ => responseBody,
+            };
+
+            return parsedValue.ToFormula();
+        }
+        catch (JsonException)
+        {
+            // Not valid JSON — return the raw string.
+            return FormulaValue.New(responseBody);
+        }
+    }
+
+    private string GetMethod()
+    {
+        EnumExpression<HttpMethodTypeWrapper>? methodExpression = this.Model.Method;
+        if (methodExpression is null)
+        {
+            return "GET";
+        }
+
+        HttpMethodTypeWrapper wrapper = this.Evaluator.GetValue(methodExpression).Value;
+        return !string.IsNullOrEmpty(wrapper.UnknownValue) ? wrapper.UnknownValue! : wrapper.Value.ToString().ToUpperInvariant();
+    }
+
+    private string GetUrl() =>
+        this.Evaluator.GetValue(
+            Throw.IfNull(
+                this.Model.Url,
+                $"{nameof(this.Model)}.{nameof(this.Model.Url)}")).Value;
+
+    private Dictionary<string, string>? GetHeaders()
+    {
+        if (this.Model.Headers is null || this.Model.Headers.Count == 0)
+        {
+            return null;
+        }
+
+        Dictionary<string, string> result = new(StringComparer.OrdinalIgnoreCase);
+        foreach (KeyValuePair<string, StringExpression> header in this.Model.Headers)
+        {
+            string value = this.Evaluator.GetValue(header.Value).Value;
+            if (!string.IsNullOrEmpty(value))
+            {
+                result[header.Key] = value;
+            }
+        }
+
+        return result.Count == 0 ? null : result;
+    }
+
+    private (string? Body, string? ContentType) GetBody()
+    {
+        switch (this.Model.Body)
+        {
+            case null:
+            case NoRequestContent:
+                return (null, null);
+
+            case JsonRequestContent jsonContent when jsonContent.Content is not null:
+            {
+                FormulaValue formula = this.Evaluator.GetValue(jsonContent.Content).Value.ToFormula();
+                string json = formula.ToJson().ToJsonString();
+                return (json, "application/json");
+            }
+
+            case RawRequestContent rawContent:
+            {
+                string? content = rawContent.Content is null
+                        ? null
+                        : this.Evaluator.GetValue(rawContent.Content).Value;
+
+                string? contentType = rawContent.ContentType is null
+                        ? null
+                        : this.Evaluator.GetValue(rawContent.ContentType).Value;
+
+                return (content, string.IsNullOrEmpty(contentType) ? null : contentType);
+            }
+
+            default:
+                return (null, null);
+        }
+    }
+
+    private TimeSpan? GetTimeout()
+    {
+        if (this.Model.RequestTimeoutInMilliseconds is null || this.Model.RequestTimeoutInMillisecondsIsDefaultValue)
+        {
+            return null;
+        }
+
+        long value = this.Evaluator.GetValue(this.Model.RequestTimeoutInMilliseconds).Value;
+        return value > 0 ? TimeSpan.FromMilliseconds(value) : null;
+    }
+
+    private Dictionary<string, string>? GetQueryParameters()
+    {
+        if (this.Model.QueryParameters is null || this.Model.QueryParameters.Count == 0)
+        {
+            return null;
+        }
+
+        Dictionary<string, string> result = new(StringComparer.Ordinal);
+        foreach (KeyValuePair<string, ValueExpression> parameter in this.Model.QueryParameters)
+        {
+            if (string.IsNullOrEmpty(parameter.Key) || parameter.Value is null)
+            {
+                continue;
+            }
+
+            object? rawValue = this.Evaluator.GetValue(parameter.Value).Value.ToObject();
+            string? formatted = FormatQueryValue(rawValue);
+            if (formatted is not null)
+            {
+                result[parameter.Key] = formatted;
+            }
+        }
+
+        return result.Count == 0 ? null : result;
+    }
+
+    private static string? FormatQueryValue(object? value) =>
+        value switch
+        {
+            null => null,
+            string s => s,
+            bool b => b ? "true" : "false",
+            IFormattable formattable => formattable.ToString(null, System.Globalization.CultureInfo.InvariantCulture),
+            _ => value.ToString(),
+        };
+
+    private string? GetConversationId()
+    {
+        if (this.Model.ConversationId is null)
+        {
+            return null;
+        }
+
+        string value = this.Evaluator.GetValue(this.Model.ConversationId).Value;
+        return value.Length == 0 ? null : value;
+    }
+
+    private string? GetConnectionName()
+    {
+        RemoteConnection? connection = this.Model.Connection;
+        if (connection is null)
+        {
+            return null;
+        }
+
+        string? name = connection.Name is null
+            ? null
+            : this.Evaluator.GetValue(connection.Name).Value;
+
+        return string.IsNullOrEmpty(name) ? null : name;
+    }
+}

dotnet/src/Microsoft.Agents.AI.Workflows/Execution/StreamingRunEventStream.cs

@@ -77,12 +77,13 @@ internal sealed class StreamingRunEventStream : IRunEventStream
 
         try
         {
-            // Wait for the first input before starting
-            // The consumer will call EnqueueMessageAsync which signals the run loop
+            // Wait for the first input before starting.
+            // The consumer will call EnqueueMessageAsync which signals the run loop.
+            // Note: AsyncRunHandle also signals here on checkpoint resume when there are
+            // already pending requests, so the first iteration can emit a PendingRequests
+            // halt signal even without unprocessed messages.
             await this._inputWaiter.WaitForInputAsync(cancellationToken: linkedSource.Token).ConfigureAwait(false);
 
-            this._runStatus = RunStatus.Running;
-
             while (!linkedSource.Token.IsCancellationRequested)
             {
                 // Start a new run-stage activity for this input→processing→halt cycle
@@ -95,6 +96,13 @@ internal sealed class StreamingRunEventStream : IRunEventStream
                 // Events are streamed out in real-time as they happen via the event handler
                 if (this._stepRunner.HasUnprocessedMessages)
                 {
+                    // Flip to Running only when there's actual work to process.
+                    // This is intentionally inside the HasUnprocessedMessages branch so
+                    // that stale input signals cannot transiently flip status back to
+                    // Running after a prior halt has already been observed by callers
+                    // (e.g. Run.ResumeAsync returning after reading an Idle halt signal).
+                    this._runStatus = RunStatus.Running;
+
                     // Emit WorkflowStartedEvent only when there's actual work to process
                     // This avoids spurious events on timeout-only loop iterations
                     await this._eventChannel.Writer.WriteAsync(new WorkflowStartedEvent(), linkedSource.Token).ConfigureAwait(false);
@@ -129,9 +137,6 @@ internal sealed class StreamingRunEventStream : IRunEventStream
                 // Wait for next input from the consumer
                 // Works for both Idle (no work) and PendingRequests (waiting for responses)
                 await this._inputWaiter.WaitForInputAsync(linkedSource.Token).ConfigureAwait(false);
-
-                // When signaled, resume running
-                this._runStatus = RunStatus.Running;
             }
         }
         catch (OperationCanceledException)

dotnet/src/Microsoft.Agents.AI/CompatibilitySuppressions.xml

@@ -1,6 +1,20 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- https://learn.microsoft.com/dotnet/fundamentals/package-validation/diagnostic-ids -->
 <Suppressions xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.BeginInvoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken,System.AsyncCallback,System.Object)</Target>
+    <Left>lib/net10.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.Invoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net10.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentInlineSkill.#ctor(Microsoft.Agents.AI.AgentSkillFrontmatter,System.String)</Target>
@@ -29,6 +43,13 @@
     <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net10.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentSkillsProvider.#ctor(Microsoft.Agents.AI.AgentInlineSkill[])</Target>
@@ -43,6 +64,20 @@
     <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.BeginInvoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken,System.AsyncCallback,System.Object)</Target>
+    <Left>lib/net472/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.Invoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net472/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentInlineSkill.#ctor(Microsoft.Agents.AI.AgentSkillFrontmatter,System.String)</Target>
@@ -71,6 +106,13 @@
     <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net472/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentSkillsProvider.#ctor(Microsoft.Agents.AI.AgentInlineSkill[])</Target>
@@ -85,6 +127,20 @@
     <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.BeginInvoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken,System.AsyncCallback,System.Object)</Target>
+    <Left>lib/net8.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.Invoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net8.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentInlineSkill.#ctor(Microsoft.Agents.AI.AgentSkillFrontmatter,System.String)</Target>
@@ -113,6 +169,13 @@
     <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net8.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentSkillsProvider.#ctor(Microsoft.Agents.AI.AgentInlineSkill[])</Target>
@@ -127,6 +190,20 @@
     <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.BeginInvoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken,System.AsyncCallback,System.Object)</Target>
+    <Left>lib/net9.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.Invoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net9.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentInlineSkill.#ctor(Microsoft.Agents.AI.AgentSkillFrontmatter,System.String)</Target>
@@ -155,6 +232,13 @@
     <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/net9.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentSkillsProvider.#ctor(Microsoft.Agents.AI.AgentInlineSkill[])</Target>
@@ -169,6 +253,20 @@
     <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.BeginInvoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken,System.AsyncCallback,System.Object)</Target>
+    <Left>lib/netstandard2.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentFileSkillScriptRunner.Invoke(Microsoft.Agents.AI.AgentFileSkill,Microsoft.Agents.AI.AgentFileSkillScript,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/netstandard2.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentInlineSkill.#ctor(Microsoft.Agents.AI.AgentSkillFrontmatter,System.String)</Target>
@@ -197,6 +295,13 @@
     <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,Microsoft.Extensions.AI.AIFunctionArguments,System.Threading.CancellationToken)</Target>
+    <Left>lib/netstandard2.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Microsoft.Agents.AI.AgentSkillsProvider.#ctor(Microsoft.Agents.AI.AgentInlineSkill[])</Target>
@@ -211,4 +316,39 @@
     <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0005</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,System.Nullable{System.Text.Json.JsonElement},System.IServiceProvider,System.Threading.CancellationToken)</Target>
+    <Left>lib/net10.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net10.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0005</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,System.Nullable{System.Text.Json.JsonElement},System.IServiceProvider,System.Threading.CancellationToken)</Target>
+    <Left>lib/net472/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net472/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0005</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,System.Nullable{System.Text.Json.JsonElement},System.IServiceProvider,System.Threading.CancellationToken)</Target>
+    <Left>lib/net8.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net8.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0005</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,System.Nullable{System.Text.Json.JsonElement},System.IServiceProvider,System.Threading.CancellationToken)</Target>
+    <Left>lib/net9.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/net9.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0005</DiagnosticId>
+    <Target>M:Microsoft.Agents.AI.AgentSkillScript.RunAsync(Microsoft.Agents.AI.AgentSkill,System.Nullable{System.Text.Json.JsonElement},System.IServiceProvider,System.Threading.CancellationToken)</Target>
+    <Left>lib/netstandard2.0/Microsoft.Agents.AI.dll</Left>
+    <Right>lib/netstandard2.0/Microsoft.Agents.AI.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
 </Suppressions>

dotnet/src/Microsoft.Agents.AI/Skills/AgentSkill.cs

@@ -35,7 +35,8 @@ public abstract class AgentSkill
     /// Gets the full skill content.
     /// </summary>
     /// <remarks>
-    /// For file-based skills this is the raw SKILL.md file content.
+    /// For file-based skills this is the raw SKILL.md file content, optionally
+    /// augmented with a synthesized scripts block when scripts are present.
     /// For code-defined skills this is a synthesized XML document
     /// containing name, description, and body (instructions, resources, scripts).
     /// </remarks>

dotnet/src/Microsoft.Agents.AI/Skills/AgentSkillScript.cs

@@ -1,10 +1,10 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using System;
 using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 using Microsoft.Shared.DiagnosticIds;
 using Microsoft.Shared.Diagnostics;
 
@@ -46,8 +46,9 @@ public abstract class AgentSkillScript
     /// Runs the script with the given arguments.
     /// </summary>
     /// <param name="skill">The skill that owns this script.</param>
-    /// <param name="arguments">Arguments for script execution.</param>
+    /// <param name="arguments">Raw JSON arguments for script execution, preserving the original format (object or array) sent by the caller.</param>
+    /// <param name="serviceProvider">Optional service provider for dependency injection.</param>
     /// <param name="cancellationToken">Cancellation token.</param>
     /// <returns>The script execution result.</returns>
-    public abstract Task<object?> RunAsync(AgentSkill skill, AIFunctionArguments arguments, CancellationToken cancellationToken = default);
+    public abstract Task<object?> RunAsync(AgentSkill skill, JsonElement? arguments, IServiceProvider? serviceProvider, CancellationToken cancellationToken = default);
 }

dotnet/src/Microsoft.Agents.AI/Skills/AgentSkillsProvider.cs

@@ -6,6 +6,7 @@ using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Security;
 using System.Text;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.AI;
@@ -243,7 +244,7 @@ public sealed partial class AgentSkillsProvider : AIContextProvider
         }
 
         AIFunction scriptFunction = AIFunctionFactory.Create(
-            (string skillName, string scriptName, IDictionary<string, object?>? arguments = null, IServiceProvider? serviceProvider = null, CancellationToken cancellationToken = default) =>
+            (string skillName, string scriptName, JsonElement? arguments = null, IServiceProvider? serviceProvider = null, CancellationToken cancellationToken = default) =>
                 this.RunSkillScriptAsync(skills, skillName, scriptName, arguments, serviceProvider, cancellationToken),
             name: "run_skill_script",
             description: "Runs a script associated with a skill.");
@@ -340,7 +341,7 @@ public sealed partial class AgentSkillsProvider : AIContextProvider
         }
     }
 
-    private async Task<object?> RunSkillScriptAsync(IList<AgentSkill> skills, string skillName, string scriptName, IDictionary<string, object?>? arguments = null, IServiceProvider? serviceProvider = null, CancellationToken cancellationToken = default)
+    private async Task<object?> RunSkillScriptAsync(IList<AgentSkill> skills, string skillName, string scriptName, JsonElement? arguments = null, IServiceProvider? serviceProvider = null, CancellationToken cancellationToken = default)
     {
         if (string.IsNullOrWhiteSpace(skillName))
         {
@@ -366,7 +367,7 @@ public sealed partial class AgentSkillsProvider : AIContextProvider
 
         try
         {
-            return await script.RunAsync(skill, new AIFunctionArguments(arguments) { Services = serviceProvider }, cancellationToken).ConfigureAwait(false);
+            return await script.RunAsync(skill, arguments, serviceProvider, cancellationToken).ConfigureAwait(false);
         }
         catch (Exception ex)
         {

dotnet/src/Microsoft.Agents.AI/Skills/File/AgentFileSkill.cs

@@ -15,6 +15,8 @@ public sealed class AgentFileSkill : AgentSkill
 {
     private readonly IReadOnlyList<AgentSkillResource> _resources;
     private readonly IReadOnlyList<AgentSkillScript> _scripts;
+    private readonly string _originalContent;
+    private string? _content;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="AgentFileSkill"/> class.
@@ -32,7 +34,7 @@ public sealed class AgentFileSkill : AgentSkill
         IReadOnlyList<AgentSkillScript>? scripts = null)
     {
         this.Frontmatter = Throw.IfNull(frontmatter);
-        this.Content = Throw.IfNull(content);
+        this._originalContent = Throw.IfNull(content);
         this.Path = Throw.IfNullOrWhitespace(path);
         this._resources = resources ?? [];
         this._scripts = scripts ?? [];
@@ -42,7 +44,18 @@ public sealed class AgentFileSkill : AgentSkill
     public override AgentSkillFrontmatter Frontmatter { get; }
 
     /// <inheritdoc/>
-    public override string Content { get; }
+    /// <remarks>
+    /// Returns the raw SKILL.md content. When the skill has scripts, a
+    /// <c>&lt;scripts&gt;&lt;script name="..."&gt;&lt;parameters_schema&gt;...&lt;/parameters_schema&gt;&lt;/script&gt;&lt;/scripts&gt;</c>
+    /// block is appended with a per-script entry describing the expected argument format.
+    /// The result is cached after the first access.
+    /// </remarks>
+    public override string Content
+    {
+        get => this._content ??= this._scripts is { Count: > 0 }
+            ? this._originalContent + AgentInlineSkillContentBuilder.BuildScriptsBlock(this._scripts)
+            : this._originalContent;
+    }
 
     /// <summary>
     /// Gets the directory path where the skill was discovered.

dotnet/src/Microsoft.Agents.AI/Skills/File/AgentFileSkillScript.cs

@@ -2,9 +2,9 @@
 
 using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 using Microsoft.Shared.DiagnosticIds;
 using Microsoft.Shared.Diagnostics;
 
@@ -16,6 +16,11 @@ namespace Microsoft.Agents.AI;
 [Experimental(DiagnosticIds.Experiments.AgentsAIExperiments)]
 public sealed class AgentFileSkillScript : AgentSkillScript
 {
+    /// <summary>
+    /// Cached JSON schema element describing the expected argument format: a string array of CLI arguments.
+    /// </summary>
+    private static readonly JsonElement s_defaultSchema = CreateDefaultSchema();
+
     private readonly AgentFileSkillScriptRunner? _runner;
 
     /// <summary>
@@ -37,7 +42,14 @@ public sealed class AgentFileSkillScript : AgentSkillScript
     public string FullPath { get; }
 
     /// <inheritdoc/>
-    public override async Task<object?> RunAsync(AgentSkill skill, AIFunctionArguments arguments, CancellationToken cancellationToken = default)
+    /// <remarks>
+    /// Returns a fixed schema describing a string array of CLI arguments:
+    /// <c>{"type":"array","items":{"type":"string"}}</c>.
+    /// </remarks>
+    public override JsonElement? ParametersSchema => s_defaultSchema;
+
+    /// <inheritdoc/>
+    public override async Task<object?> RunAsync(AgentSkill skill, JsonElement? arguments, IServiceProvider? serviceProvider, CancellationToken cancellationToken = default)
     {
         if (skill is not AgentFileSkill fileSkill)
         {
@@ -51,6 +63,12 @@ public sealed class AgentFileSkillScript : AgentSkillScript
                 $"Supply a script runner when constructing {nameof(AgentFileSkillsSource)} to enable script execution.");
         }
 
-        return await this._runner(fileSkill, this, arguments, cancellationToken).ConfigureAwait(false);
+        return await this._runner(fileSkill, this, arguments, serviceProvider, cancellationToken).ConfigureAwait(false);
+    }
+
+    private static JsonElement CreateDefaultSchema()
+    {
+        using JsonDocument document = JsonDocument.Parse("""{"type":"array","items":{"type":"string"}}""");
+        return document.RootElement.Clone();
     }
 }

dotnet/src/Microsoft.Agents.AI/Skills/File/AgentFileSkillScriptRunner.cs

@@ -1,9 +1,10 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI;
@@ -13,15 +14,19 @@ namespace Microsoft.Agents.AI;
 /// </summary>
 /// <remarks>
 /// Implementations determine the execution strategy (e.g., local subprocess, hosted code execution environment).
+/// The <paramref name="arguments"/> parameter preserves the raw JSON sent by the caller, in the shape
+/// described by <see cref="AgentFileSkillScript.ParametersSchema"/>.
 /// </remarks>
 /// <param name="skill">The skill that owns the script.</param>
 /// <param name="script">The file-based script to run.</param>
-/// <param name="arguments">Optional arguments for the script, provided by the agent/LLM.</param>
+/// <param name="arguments">Raw JSON arguments for the script, in the shape described by <see cref="AgentFileSkillScript.ParametersSchema"/>.</param>
+/// <param name="serviceProvider">Optional service provider for dependency injection.</param>
 /// <param name="cancellationToken">Cancellation token.</param>
 /// <returns>The script execution result.</returns>
 [Experimental(DiagnosticIds.Experiments.AgentsAIExperiments)]
 public delegate Task<object?> AgentFileSkillScriptRunner(
     AgentFileSkill skill,
     AgentFileSkillScript script,
-    AIFunctionArguments arguments,
+    JsonElement? arguments,
+    IServiceProvider? serviceProvider,
     CancellationToken cancellationToken);

dotnet/src/Microsoft.Agents.AI/Skills/Programmatic/AgentInlineSkillContentBuilder.cs

@@ -59,36 +59,60 @@ internal static class AgentInlineSkillContentBuilder
 
         if (scripts is { Count: > 0 })
         {
-            sb.Append("\n\n<scripts>\n");
-            foreach (var script in scripts)
-            {
-                var parametersSchema = script.ParametersSchema;
-
-                if (script.Description is null && parametersSchema is null)
-                {
-                    sb.Append($"  <script name=\"{EscapeXmlString(script.Name)}\"/>\n");
-                }
-                else
-                {
-                    sb.Append(script.Description is not null
-                        ? $"  <script name=\"{EscapeXmlString(script.Name)}\" description=\"{EscapeXmlString(script.Description)}\">\n"
-                        : $"  <script name=\"{EscapeXmlString(script.Name)}\">\n");
-
-                    if (parametersSchema is not null)
-                    {
-                        sb.Append($"    <parameters_schema>{EscapeXmlString(parametersSchema.Value.GetRawText(), preserveQuotes: true)}</parameters_schema>\n");
-                    }
-
-                    sb.Append("  </script>\n");
-                }
-            }
-
-            sb.Append("</scripts>");
+            sb.Append('\n');
+            sb.Append(BuildScriptsBlock(scripts));
         }
 
         return sb.ToString();
     }
 
+    /// <summary>
+    /// Builds a <c>&lt;scripts&gt;...&lt;/scripts&gt;</c> XML block for the given scripts.
+    /// Each script is emitted as a <c>&lt;script name="..."&gt;</c> element with optional
+    /// <c>description</c> attribute and <c>&lt;parameters_schema&gt;</c> child element.
+    /// </summary>
+    /// <param name="scripts">The scripts to include in the block.</param>
+    /// <returns>An XML string starting with <c>\n&lt;scripts&gt;</c>, or an empty string if the list is empty.</returns>
+    public static string BuildScriptsBlock(IReadOnlyList<AgentSkillScript> scripts)
+    {
+        _ = Throw.IfNull(scripts);
+
+        if (scripts.Count == 0)
+        {
+            return string.Empty;
+        }
+
+        var sb = new StringBuilder();
+        sb.Append("\n<scripts>\n");
+
+        foreach (var script in scripts)
+        {
+            var parametersSchema = script.ParametersSchema;
+
+            if (script.Description is null && parametersSchema is null)
+            {
+                sb.Append($"  <script name=\"{EscapeXmlString(script.Name)}\"/>\n");
+            }
+            else
+            {
+                sb.Append(script.Description is not null
+                    ? $"  <script name=\"{EscapeXmlString(script.Name)}\" description=\"{EscapeXmlString(script.Description)}\">\n"
+                    : $"  <script name=\"{EscapeXmlString(script.Name)}\">\n");
+
+                if (parametersSchema is not null)
+                {
+                    sb.Append($"    <parameters_schema>{EscapeXmlString(parametersSchema.Value.GetRawText(), preserveQuotes: true)}</parameters_schema>\n");
+                }
+
+                sb.Append("  </script>\n");
+            }
+        }
+
+        sb.Append("</scripts>");
+
+        return sb.ToString();
+    }
+
     /// <summary>
     /// Escapes XML special characters: always escapes <c>&amp;</c>, <c>&lt;</c>, <c>&gt;</c>,
     /// <c>&quot;</c>, and <c>&apos;</c>. When <paramref name="preserveQuotes"/> is <see langword="true"/>,

dotnet/src/Microsoft.Agents.AI/Skills/Programmatic/AgentInlineSkillScript.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
 using System.Text.Json;
@@ -67,8 +68,42 @@ internal sealed class AgentInlineSkillScript : AgentSkillScript
     public override JsonElement? ParametersSchema => this._function.JsonSchema;
 
     /// <inheritdoc/>
-    public override async Task<object?> RunAsync(AgentSkill skill, AIFunctionArguments arguments, CancellationToken cancellationToken = default)
+    public override async Task<object?> RunAsync(AgentSkill skill, JsonElement? arguments, IServiceProvider? serviceProvider, CancellationToken cancellationToken = default)
     {
-        return await this._function.InvokeAsync(arguments, cancellationToken).ConfigureAwait(false);
+        var funcArgs = ConvertToFunctionArguments(arguments);
+        funcArgs.Services = serviceProvider;
+
+        return await this._function.InvokeAsync(funcArgs, cancellationToken).ConfigureAwait(false);
+    }
+
+    /// <summary>
+    /// Converts a raw <see cref="JsonElement"/> to <see cref="AIFunctionArguments"/> for delegate invocation.
+    /// </summary>
+    /// <exception cref="InvalidOperationException">
+    /// Thrown when <paramref name="arguments"/> is provided but is not a JSON object.
+    /// Inline skill scripts expect arguments as a JSON object whose properties map to the delegate's parameters.
+    /// </exception>
+    private static AIFunctionArguments ConvertToFunctionArguments(JsonElement? arguments)
+    {
+        if (arguments is null ||
+            arguments.Value.ValueKind == JsonValueKind.Null ||
+            arguments.Value.ValueKind == JsonValueKind.Undefined)
+        {
+            return [];
+        }
+
+        if (arguments.Value.ValueKind != JsonValueKind.Object)
+        {
+            throw new InvalidOperationException(
+                $"Inline skill scripts expect arguments as a JSON object but received a JSON element of kind '{arguments.Value.ValueKind}'.");
+        }
+
+        var dict = new Dictionary<string, object?>();
+        foreach (var property in arguments.Value.EnumerateObject())
+        {
+            dict[property.Name] = property.Value;
+        }
+
+        return new AIFunctionArguments(dict);
     }
 }

dotnet/src/Shared/Workflows/Execution/WorkflowFactory.cs

@@ -25,6 +25,9 @@ internal sealed class WorkflowFactory(string workflowFile, Uri foundryEndpoint)
     // Assign to provide MCP tool capabilities
     public IMcpToolHandler? McpToolHandler { get; init; }
 
+    // Assign to enable HttpRequestAction support
+    public IHttpRequestHandler? HttpRequestHandler { get; init; }
+
     /// <summary>
     /// Create the workflow from the declarative YAML.  Includes definition of the
     /// <see cref="DeclarativeWorkflowOptions" /> and the associated <see cref="ResponseAgentProvider"/>.
@@ -46,6 +49,7 @@ internal sealed class WorkflowFactory(string workflowFile, Uri foundryEndpoint)
                 ConversationId = this.ConversationId,
                 LoggerFactory = this.LoggerFactory,
                 McpToolHandler = this.McpToolHandler,
+                HttpRequestHandler = this.HttpRequestHandler,
             };
 
         string workflowPath = Path.Combine(AppContext.BaseDirectory, workflowFile);

dotnet/src/Shared/Workflows/Execution/WorkflowRunner.cs

@@ -162,7 +162,10 @@ internal sealed class WorkflowRunner
 
                 case RequestInfoEvent requestInfo:
                     Debug.WriteLine($"REQUEST #{requestInfo.Request.RequestId}");
-                    externalResponse = requestInfo.Request;
+                    if (response is null || !string.Equals(requestInfo.Request.RequestId, response.RequestId, StringComparison.Ordinal))
+                    {
+                        externalResponse = requestInfo.Request;
+                    }
                     break;
 
                 case ConversationUpdateEvent invokeEvent:

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/AgentFrameworkResponseHandlerTelemetryTests.cs

@@ -164,10 +164,8 @@ public class AgentFrameworkResponseHandlerTelemetryTests
     private static (CreateResponse request, ResponseContext context) BuildRequest(string? agentKey = null)
     {
         var request = agentKey is null
-            ? AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test")
-            : AzureAIAgentServerResponsesModelFactory.CreateResponse(
-                model: "test",
-                agentReference: new AgentReference(agentKey));
+            ? new CreateResponse { Model = "test" }
+            : new CreateResponse { Model = "test", AgentReference = new AgentReference(agentKey) };
 
         request.Input = BinaryData.FromObjectAsJson(new[]
         {

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/AgentFrameworkResponseHandlerTests.cs

@@ -34,7 +34,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -72,9 +72,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            agentReference: new AgentReference("my-agent"));
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("my-agent") };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -109,7 +107,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -158,7 +156,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "my-agent");
+        var request = new CreateResponse { Model = "my-agent" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -195,7 +193,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "");
+        var request = new CreateResponse { Model = "" };
         var metadata = new Metadata();
         metadata.AdditionalProperties["entity_id"] = "entity-agent";
         request.Metadata = metadata;
@@ -235,9 +233,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            agentReference: new AgentReference("nonexistent-agent"));
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("nonexistent-agent") };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -272,9 +268,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            agentReference: new AgentReference("missing-agent"));
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("missing-agent") };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -308,7 +302,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "");
+        var request = new CreateResponse { Model = "" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -342,7 +336,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -387,7 +381,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -435,7 +429,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -478,7 +472,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -517,9 +511,11 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            instructions: "You are a helpful assistant.");
+        var request = new CreateResponse
+        {
+            Model = "test",
+            Instructions = "You are a helpful assistant.",
+        };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -557,7 +553,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -598,9 +594,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            agentReference: new AgentReference("agent-2"));
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("agent-2") };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -637,7 +631,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",
@@ -674,7 +668,7 @@ public class AgentFrameworkResponseHandlerTests
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
 
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = BinaryData.FromObjectAsJson(new[]
         {
             new { type = "message", id = "msg_1", status = "completed", role = "user",

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/DelegatingResponsesClientTests.cs

@@ -0,0 +1,453 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Net;
+using System.Net.Http;
+using System.Reflection;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Azure.AI.Extensions.OpenAI;
+using Microsoft.Agents.AI.Foundry.Hosting;
+using Microsoft.Extensions.AI;
+using OpenAI;
+using OpenAI.Responses;
+
+#pragma warning disable OPENAI001, SCME0001, SCME0002, MEAI001
+
+namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+
+/// <summary>
+/// Verifies that <see cref="DelegatingResponsesClient"/> preserves user-supplied client options
+/// (Transport, RetryPolicy, UserAgentApplicationId, OrganizationId, ProjectId) and adds the
+/// hosted-agent User-Agent supplement on every outgoing request, including streaming.
+/// Covers both the Azure-flavored <see cref="ProjectResponsesClient"/> and the native OpenAI
+/// <see cref="ResponsesClient"/>.
+/// </summary>
+public sealed partial class DelegatingResponsesClientTests
+{
+    private const string TestEndpoint = "https://fake-foundry.example.com/api/projects/fake-prj";
+    private const string OpenAIEndpoint = "https://fake-openai.example.com/v1";
+    private const string Deployment = "fake-deployment";
+
+    [System.Text.RegularExpressions.GeneratedRegex("foundry-hosting/agent-framework-dotnet")]
+    private static partial System.Text.RegularExpressions.Regex SupplementRegex();
+
+    [Fact]
+    public async Task Polyfill_NonStreaming_PreservesAppId_ThroughCustomTransport_AddsSupplementAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("MEAI/", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+        Assert.StartsWith(TestEndpoint, req.Uri);
+    }
+
+    [Fact]
+    public async Task Polyfill_Streaming_PreservesAppId_ThroughCustomTransport_AddsSupplementAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler(MinimalSseResponse());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        await foreach (var _ in chat.GetStreamingResponseAsync("hello"))
+        {
+        }
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("MEAI/", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+        Assert.StartsWith(TestEndpoint, req.Uri);
+    }
+
+    [Fact]
+    public async Task Polyfill_PreservesOrganizationAndProjectHeadersAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient,
+            userAgentApplicationId: "MY_APP_ID",
+            organizationId: "org_xyz",
+            projectId: "proj_abc");
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+    }
+
+    [Fact]
+    public async Task Polyfill_HonorsUserSuppliedRetryPolicy_ByCountingRetriesAsync()
+    {
+        // Arrange
+        var retryPolicy = new CountingRetryPolicy(extraAttempts: 2);
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID", retryPolicy: retryPolicy);
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert: retry policy ran (1 + 2 extras = 3 attempts).
+        Assert.Equal(3, handler.Requests.Count);
+        Assert.Equal(3, retryPolicy.InvocationCount);
+        foreach (var req in handler.Requests)
+        {
+            Assert.Contains("MY_APP_ID", req.UserAgent);
+            Assert.Contains("MEAI/", req.UserAgent);
+            Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+        }
+    }
+
+    [Fact]
+    public async Task Baseline_NonStreaming_DoesNotInjectSupplementAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var chat = inner.AsIChatClient(Deployment);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("MEAI/", req.UserAgent);
+        Assert.DoesNotContain("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+    }
+
+    [Fact]
+    public async Task Polyfill_NativeOpenAIResponsesClient_NonStreaming_AddsSupplementAsync()
+    {
+        // Arrange: use the NATIVE OpenAI SDK ResponsesClient (no Foundry / Azure project involved).
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildOpenAIInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("MEAI/", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+        Assert.StartsWith(OpenAIEndpoint, req.Uri);
+    }
+
+    [Fact]
+    public async Task Polyfill_NativeOpenAIResponsesClient_Streaming_AddsSupplementAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler(MinimalSseResponse());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildOpenAIInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        await foreach (var _ in chat.GetStreamingResponseAsync("hello"))
+        {
+        }
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("MEAI/", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+        Assert.StartsWith(OpenAIEndpoint, req.Uri);
+    }
+
+    [Theory]
+    [InlineData("DeleteResponseAsync")]
+    [InlineData("CancelResponseAsync")]
+    [InlineData("GetInputTokenCountAsync")]
+    [InlineData("CompactResponseAsync")]
+    [InlineData("GetResponseInputItemCollectionPageAsync")]
+    public async Task Polyfill_AncillaryProtocolMethod_AddsSupplementAsync(string method)
+    {
+        // Arrange: hit the wrapper DIRECTLY (no MEAI in the chain) to simulate user code that
+        // grabs the underlying ResponsesClient via chat.GetService<ResponsesClient>() and invokes
+        // a non-Create/Get protocol method. This is the regression path: without overriding these,
+        // the wrapper's dummy throwing pipeline would fire.
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildOpenAIInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        var wrapper = new DelegatingResponsesClient(inner);
+
+        // Act
+        switch (method)
+        {
+            case "DeleteResponseAsync":
+                _ = await wrapper.DeleteResponseAsync("resp_1", options: null!);
+                break;
+            case "CancelResponseAsync":
+                _ = await wrapper.CancelResponseAsync("resp_1", options: null!);
+                break;
+            case "GetInputTokenCountAsync":
+                _ = await wrapper.GetInputTokenCountAsync("application/json", BinaryContent.Create(BinaryData.FromString("{}")));
+                break;
+            case "CompactResponseAsync":
+                _ = await wrapper.CompactResponseAsync("application/json", BinaryContent.Create(BinaryData.FromString("{}")));
+                break;
+            case "GetResponseInputItemCollectionPageAsync":
+                _ = await wrapper.GetResponseInputItemCollectionPageAsync("resp_1", limit: null, order: "asc", after: "a", before: "b", options: null!);
+                break;
+            default:
+                Assert.Fail($"Unhandled method: {method}");
+                break;
+        }
+
+        // Assert
+        var req = Assert.Single(handler.Requests);
+        Assert.Contains("MY_APP_ID", req.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", req.UserAgent);
+    }
+
+    [Fact]
+    public async Task Polyfill_RetryWithinCall_DoesNotDuplicateSupplementInUserAgentAsync()
+    {
+        // Arrange: a custom retry policy that re-runs the inner pipeline on the SAME message,
+        // so the per-call HostedAgentUserAgentPolicy fires multiple times against the same headers.
+        // The policy's Contains-guard must prevent the supplement from appearing twice.
+        var retryPolicy = new CountingRetryPolicy(extraAttempts: 2);
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID", retryPolicy: retryPolicy);
+        var chat = MakeWithDelegating(inner);
+
+        // Act
+        _ = await chat.GetResponseAsync("hello");
+
+        // Assert: each retry attempt must have exactly ONE foundry-hosting segment, never two.
+        Assert.Equal(3, handler.Requests.Count);
+        foreach (var req in handler.Requests)
+        {
+            int matches = SupplementRegex().Matches(req.UserAgent).Count;
+            Assert.True(matches == 1, $"Expected exactly one foundry-hosting segment per retry attempt, got {matches}. UA: {req.UserAgent}");
+        }
+    }
+
+    [Fact]
+    public async Task TryApplyUserAgent_CalledTwiceOnSameAgent_DoesNotDoubleWrapAsync()
+    {
+        // Arrange: build a real ChatClientAgent whose IChatClient resolves to MEAI's
+        // OpenAIResponsesChatClient → ProjectResponsesClient (with a fake transport).
+        using var handler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var inner = BuildInner(httpClient, userAgentApplicationId: "MY_APP_ID");
+        IChatClient chatClient = inner.AsIChatClient(Deployment);
+        AIAgent agent = new ChatClientAgent(chatClient);
+
+        // Act: apply twice.
+        FoundryHostingExtensions.TryApplyUserAgent(agent);
+        FoundryHostingExtensions.TryApplyUserAgent(agent);
+
+        // Assert: invoking the agent produces exactly ONE outbound request whose UA contains
+        // the supplement EXACTLY ONCE (would be twice if the wrapper were nested).
+        _ = await chatClient.GetResponseAsync("hello");
+        var req = Assert.Single(handler.Requests);
+        int matches = SupplementRegex().Matches(req.UserAgent).Count;
+        Assert.True(matches == 1, $"Expected exactly one foundry-hosting segment, got {matches}. UA: {req.UserAgent}");
+    }
+
+    [Fact]
+    public void OpenAIResponsesChatClient_ResponseClientField_ReflectionGuard()
+    {
+        // Guards the polyfill's reflection target. Failure here means MEAI internals
+        // changed and the polyfill needs updating.
+        var meaiType = typeof(MicrosoftExtensionsAIResponsesExtensions).Assembly
+            .GetType("Microsoft.Extensions.AI.OpenAIResponsesChatClient");
+        Assert.NotNull(meaiType);
+
+        var field = meaiType!.GetField("_responseClient", BindingFlags.NonPublic | BindingFlags.Instance);
+        Assert.NotNull(field);
+        Assert.True(typeof(ResponsesClient).IsAssignableFrom(field!.FieldType),
+            $"Expected _responseClient to be assignable to ResponsesClient but was {field.FieldType}.");
+    }
+
+    [Fact]
+    public void ResponsesClient_PipelineProperty_ReflectionGuard()
+    {
+        // The polyfill design assumes ResponsesClient.Pipeline remains accessible.
+        var pipelineProp = typeof(ResponsesClient).GetProperty("Pipeline", BindingFlags.Public | BindingFlags.Instance);
+        Assert.NotNull(pipelineProp);
+        Assert.Equal(typeof(ClientPipeline), pipelineProp!.PropertyType);
+    }
+
+    private static IChatClient MakeWithDelegating(ResponsesClient inner)
+    {
+        IChatClient meai = inner.AsIChatClient(Deployment);
+        var meaiType = meai.GetType();
+        var field = meaiType.GetField("_responseClient", BindingFlags.NonPublic | BindingFlags.Instance)!;
+        field.SetValue(meai, new DelegatingResponsesClient(inner));
+        return meai;
+    }
+
+    private static ProjectResponsesClient BuildInner(
+        HttpClient httpClient,
+        string? userAgentApplicationId = null,
+        string? organizationId = null,
+        string? projectId = null,
+        PipelinePolicy? retryPolicy = null)
+    {
+        var options = new ProjectResponsesClientOptions
+        {
+            Transport = new HttpClientPipelineTransport(httpClient),
+        };
+        if (userAgentApplicationId is not null)
+        {
+            options.UserAgentApplicationId = userAgentApplicationId;
+        }
+        if (organizationId is not null)
+        {
+            options.OrganizationId = organizationId;
+        }
+        if (projectId is not null)
+        {
+            options.ProjectId = projectId;
+        }
+        if (retryPolicy is not null)
+        {
+            options.RetryPolicy = retryPolicy;
+        }
+
+        return new ProjectResponsesClient(new Uri(TestEndpoint), new FakeAuthenticationTokenProvider(), options);
+    }
+
+    private static ResponsesClient BuildOpenAIInner(
+        HttpClient httpClient,
+        string? userAgentApplicationId = null)
+    {
+        var options = new OpenAIClientOptions
+        {
+            Transport = new HttpClientPipelineTransport(httpClient),
+            Endpoint = new Uri(OpenAIEndpoint),
+        };
+        if (userAgentApplicationId is not null)
+        {
+            options.UserAgentApplicationId = userAgentApplicationId;
+        }
+
+        return new ResponsesClient(new ApiKeyCredential("test-key"), options);
+    }
+
+    private static string MinimalResponseJson() => """
+        {
+          "id":"resp_1","object":"response","created_at":1700000000,"status":"completed",
+          "model":"fake","output":[],"usage":{"input_tokens":1,"output_tokens":1,"total_tokens":2}
+        }
+        """;
+
+    private static string MinimalSseResponse()
+    {
+        var sb = new StringBuilder();
+        sb.Append("event: response.completed\n");
+        sb.Append("data: ").Append("""{"type":"response.completed","response":{"id":"resp_1","object":"response","created_at":1700000000,"status":"completed","model":"fake","output":[],"usage":{"input_tokens":1,"output_tokens":1,"total_tokens":2}}}""").Append("\n\n");
+        sb.Append("data: [DONE]\n\n");
+        return sb.ToString();
+    }
+
+    private sealed class RecordingHandler : HttpClientHandler
+    {
+        private readonly string _body;
+        public List<RecordedRequest> Requests { get; } = [];
+
+        public RecordingHandler(string body)
+        {
+            this._body = body;
+        }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            string ua = request.Headers.TryGetValues("User-Agent", out var values)
+                ? string.Join(",", values)
+                : "(none)";
+            this.Requests.Add(new RecordedRequest(request.Method.Method, request.RequestUri?.ToString() ?? "?", ua));
+
+            var resp = new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(this._body, Encoding.UTF8, "application/json"),
+                RequestMessage = request,
+            };
+            return Task.FromResult(resp);
+        }
+    }
+
+    private readonly record struct RecordedRequest(string Method, string Uri, string UserAgent);
+
+    private sealed class CountingRetryPolicy : PipelinePolicy
+    {
+        private readonly int _extraAttempts;
+        public int InvocationCount { get; private set; }
+
+        public CountingRetryPolicy(int extraAttempts)
+        {
+            this._extraAttempts = extraAttempts;
+        }
+
+        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        {
+            for (int i = 0; i <= this._extraAttempts; i++)
+            {
+                this.InvocationCount++;
+                ProcessNext(message, pipeline, currentIndex);
+            }
+        }
+
+        public override async ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        {
+            for (int i = 0; i <= this._extraAttempts; i++)
+            {
+                this.InvocationCount++;
+                await ProcessNextAsync(message, pipeline, currentIndex).ConfigureAwait(false);
+            }
+        }
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/FoundryToolboxTests.cs

@@ -0,0 +1,329 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Net;
+using System.Net.Http;
+using System.Text;
+using System.Threading.Tasks;
+using Azure.AI.Projects;
+using Azure.AI.Projects.Agents;
+using Microsoft.Agents.AI.Foundry.Hosting;
+using Microsoft.Extensions.AI;
+
+#pragma warning disable OPENAI001
+#pragma warning disable AAIP001
+
+namespace Microsoft.Agents.AI.Foundry.UnitTests;
+
+/// <summary>
+/// Unit tests for the <see cref="FoundryToolbox"/> class.
+/// </summary>
+public class FoundryToolboxTests
+{
+    private static readonly Uri s_testEndpoint = new("https://test.services.ai.azure.com/api/projects/test-project");
+
+    #region Parameter validation tests
+
+    [Fact]
+    public async Task GetToolboxVersionAsync_NullEndpoint_ThrowsAsync()
+    {
+        await Assert.ThrowsAsync<ArgumentNullException>(() =>
+            FoundryToolbox.GetToolboxVersionAsync(
+                projectEndpoint: null!,
+                credential: new FakeAuthenticationTokenProvider(),
+                name: "test-toolbox"));
+    }
+
+    [Fact]
+    public async Task GetToolboxVersionAsync_NullCredential_ThrowsAsync()
+    {
+        await Assert.ThrowsAsync<ArgumentNullException>(() =>
+            FoundryToolbox.GetToolboxVersionAsync(
+                projectEndpoint: s_testEndpoint,
+                credential: null!,
+                name: "test-toolbox"));
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    public async Task GetToolboxVersionAsync_InvalidName_ThrowsAsync(string? name)
+    {
+        await Assert.ThrowsAnyAsync<ArgumentException>(() =>
+            FoundryToolbox.GetToolboxVersionAsync(
+                projectEndpoint: s_testEndpoint,
+                credential: new FakeAuthenticationTokenProvider(),
+                name: name!));
+    }
+
+    [Fact]
+    public async Task GetToolsAsync_NullEndpoint_ThrowsAsync()
+    {
+        await Assert.ThrowsAsync<ArgumentNullException>(() =>
+            FoundryToolbox.GetToolsAsync(
+                projectEndpoint: null!,
+                credential: new FakeAuthenticationTokenProvider(),
+                name: "test-toolbox"));
+    }
+
+    [Fact]
+    public void ToAITools_NullToolboxVersion_Throws()
+    {
+        Assert.Throws<ArgumentNullException>(() =>
+            FoundryToolbox.ToAITools(null!));
+    }
+
+    #endregion
+
+    #region ToAITools conversion tests
+
+    [Fact]
+    public void ToAITools_EmptyTools_ReturnsEmptyList()
+    {
+        var version = ProjectsAgentsModelFactory.ToolboxVersion(
+            metadata: null,
+            id: "ver-1",
+            name: "empty-toolbox",
+            version: "v1",
+            description: "Empty",
+            createdAt: DateTimeOffset.UtcNow,
+            tools: Array.Empty<ProjectsAgentTool>(),
+            policies: null);
+
+        var tools = version.ToAITools();
+
+        Assert.Empty(tools);
+    }
+
+    [Fact]
+    public void ToAITools_NullTools_ReturnsEmptyList()
+    {
+        var version = ProjectsAgentsModelFactory.ToolboxVersion(
+            metadata: null,
+            id: "ver-1",
+            name: "null-tools-toolbox",
+            version: "v1",
+            description: "Null tools",
+            createdAt: DateTimeOffset.UtcNow,
+            tools: null,
+            policies: null);
+
+        var tools = version.ToAITools();
+
+        Assert.Empty(tools);
+    }
+
+    [Fact]
+    public void ToAITools_WithCodeInterpreterTool_ReturnsAITool()
+    {
+        var json = TestDataUtil.GetToolboxVersionResponseJson();
+        var version = ModelReaderWriter.Read<ToolboxVersion>(BinaryData.FromString(json))!;
+
+        var tools = version.ToAITools();
+
+        Assert.Single(tools);
+        Assert.IsAssignableFrom<AITool>(tools[0]);
+    }
+
+    [Fact]
+    public void ToAITools_SanitizesDecorationFieldsOnNonFunctionTools()
+    {
+        var json = TestDataUtil.GetToolboxVersionWithDecorationFieldsJson();
+        var version = ModelReaderWriter.Read<ToolboxVersion>(BinaryData.FromString(json))!;
+
+        var tools = version.ToAITools();
+
+        Assert.Single(tools);
+        Assert.IsAssignableFrom<AITool>(tools[0]);
+    }
+
+    [Fact]
+    public void SanitizeAndConvert_FunctionTool_PreservesNameAndDescription()
+    {
+        const string ToolJson = @"{""type"":""function"",""name"":""get_weather"",""description"":""Get weather"",""parameters"":{""type"":""object"",""properties"":{}}}";
+        var tool = ModelReaderWriter.Read<ProjectsAgentTool>(BinaryData.FromString(ToolJson))!;
+
+        var aiTool = FoundryToolbox.SanitizeAndConvert(tool);
+
+        Assert.NotNull(aiTool);
+        Assert.IsAssignableFrom<AITool>(aiTool);
+    }
+
+    [Fact]
+    public void SanitizeAndConvert_CodeInterpreterWithExtraFields_StripsDecorationFields()
+    {
+        const string ToolJson = @"{""type"":""code_interpreter"",""name"":""code_interpreter"",""description"":""Execute code""}";
+        var tool = ModelReaderWriter.Read<ProjectsAgentTool>(BinaryData.FromString(ToolJson))!;
+
+        var aiTool = FoundryToolbox.SanitizeAndConvert(tool);
+
+        Assert.NotNull(aiTool);
+    }
+
+    #endregion
+
+    #region Integration tests with mock HTTP
+
+    [Fact]
+    public async Task GetToolboxVersionAsync_WithExplicitVersion_FetchesVersionDirectlyAsync()
+    {
+        var versionJson = TestDataUtil.GetToolboxVersionResponseJson();
+        using var httpHandler = new HttpHandlerAssert((request) =>
+        {
+            Assert.Contains("/toolboxes/research_tools/versions/v5", request.RequestUri!.PathAndQuery);
+
+            return new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(versionJson, Encoding.UTF8, "application/json")
+            };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+        var clientOptions = new AgentAdministrationClientOptions { Transport = new HttpClientPipelineTransport(httpClient) };
+
+        var result = await FoundryToolbox.GetToolboxVersionAsync(
+            s_testEndpoint,
+            new FakeAuthenticationTokenProvider(),
+            "research_tools",
+            version: "v5",
+            clientOptions: clientOptions,
+            cancellationToken: default);
+
+        Assert.Equal("research_tools", result.Name);
+        Assert.Equal("v5", result.Version);
+        Assert.Single(result.Tools);
+    }
+
+    [Fact]
+    public async Task GetToolboxVersionAsync_WithoutVersion_ResolvesDefaultThenFetchesAsync()
+    {
+        var recordJson = TestDataUtil.GetToolboxRecordResponseJson();
+        var versionJson = TestDataUtil.GetToolboxVersionResponseJson();
+        var callCount = 0;
+
+        using var httpHandler = new HttpHandlerAssert((request) =>
+        {
+            callCount++;
+            var path = request.RequestUri!.PathAndQuery;
+
+            if (!path.Contains("/versions/"))
+            {
+                Assert.Contains("/toolboxes/research_tools", path);
+                return new HttpResponseMessage(HttpStatusCode.OK)
+                {
+                    Content = new StringContent(recordJson, Encoding.UTF8, "application/json")
+                };
+            }
+
+            Assert.Contains("/toolboxes/research_tools/versions/v5", path);
+            return new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(versionJson, Encoding.UTF8, "application/json")
+            };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+        var clientOptions = new AgentAdministrationClientOptions { Transport = new HttpClientPipelineTransport(httpClient) };
+
+        var result = await FoundryToolbox.GetToolboxVersionAsync(
+            s_testEndpoint,
+            new FakeAuthenticationTokenProvider(),
+            "research_tools",
+            version: null,
+            clientOptions: clientOptions,
+            cancellationToken: default);
+
+        Assert.Equal(2, callCount);
+        Assert.Equal("research_tools", result.Name);
+        Assert.Equal("v5", result.Version);
+    }
+
+    [Fact]
+    public async Task GetToolboxVersionAsync_ApiError_ThrowsClientResultExceptionAsync()
+    {
+        using var httpHandler = new HttpHandlerAssert((_) =>
+            new HttpResponseMessage(HttpStatusCode.NotFound)
+            {
+                Content = new StringContent("{\"error\":\"not found\"}", Encoding.UTF8, "application/json")
+            });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+        var clientOptions = new AgentAdministrationClientOptions { Transport = new HttpClientPipelineTransport(httpClient) };
+
+        await Assert.ThrowsAsync<ClientResultException>(() =>
+            FoundryToolbox.GetToolboxVersionAsync(
+                s_testEndpoint,
+                new FakeAuthenticationTokenProvider(),
+                "nonexistent-toolbox",
+                version: "v1",
+                clientOptions: clientOptions,
+                cancellationToken: default));
+    }
+
+    [Fact]
+    public async Task GetToolsAsync_ReturnsConvertedAIToolsAsync()
+    {
+        var versionJson = TestDataUtil.GetToolboxVersionResponseJson();
+        using var httpHandler = new HttpHandlerAssert((_) =>
+            new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(versionJson, Encoding.UTF8, "application/json")
+            });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+        var clientOptions = new AgentAdministrationClientOptions { Transport = new HttpClientPipelineTransport(httpClient) };
+
+        var result = await FoundryToolbox.GetToolboxVersionAsync(
+            s_testEndpoint,
+            new FakeAuthenticationTokenProvider(),
+            "research_tools",
+            version: "v5",
+            clientOptions: clientOptions,
+            cancellationToken: default);
+
+        var tools = result.ToAITools();
+
+        Assert.Single(tools);
+        Assert.IsAssignableFrom<AITool>(tools[0]);
+    }
+
+    #endregion
+
+    #region AIProjectClient extension tests
+
+    [Fact]
+    public async Task AIProjectClientExtension_GetToolboxToolsAsync_ReturnsAIToolsAsync()
+    {
+        var versionJson = TestDataUtil.GetToolboxVersionResponseJson();
+        using var httpHandler = new HttpHandlerAssert((_) =>
+            new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(versionJson, Encoding.UTF8, "application/json")
+            });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+        var clientOptions = new AIProjectClientOptions();
+        clientOptions.Transport = new HttpClientPipelineTransport(httpClient);
+        var client = new AIProjectClient(s_testEndpoint, new FakeAuthenticationTokenProvider(), clientOptions);
+
+        var tools = await client.GetToolboxToolsAsync("research_tools", version: "v5");
+
+        Assert.Single(tools);
+        Assert.IsAssignableFrom<AITool>(tools[0]);
+    }
+
+    #endregion
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/HostedOutboundUserAgentTests.cs

@@ -0,0 +1,165 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Net;
+using System.Net.Http;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Azure.AI.Extensions.OpenAI;
+using Microsoft.Agents.AI.Foundry.Hosting;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.AspNetCore.TestHost;
+using Microsoft.Extensions.AI;
+using Microsoft.Extensions.DependencyInjection;
+
+#pragma warning disable OPENAI001, SCME0001, SCME0002, MEAI001
+
+namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+
+/// <summary>
+/// End-to-end tests that exercise the FULL hosted ASP.NET Core pipeline:
+/// inbound HTTP → MapFoundryResponses → AgentFrameworkResponseHandler → TryApplyUserAgent →
+/// agent invocation → outbound HTTP from inside the hosted environment.
+/// Verifies that the hosted-agent <c>User-Agent</c> supplement reaches the outbound wire,
+/// not just the inbound request.
+/// </summary>
+public sealed class HostedOutboundUserAgentTests : IAsyncDisposable
+{
+    private const string TestEndpoint = "https://fake-foundry.example.com/api/projects/fake-prj";
+    private const string Deployment = "fake-deployment";
+
+    private WebApplication? _app;
+    private HttpClient? _inboundClient;
+    private RecordingHandler? _outboundHandler;
+
+    public async ValueTask DisposeAsync()
+    {
+        this._inboundClient?.Dispose();
+        this._outboundHandler?.Dispose();
+        if (this._app is not null)
+        {
+            await this._app.DisposeAsync();
+        }
+    }
+
+    [Fact]
+    public async Task Hosted_InboundResponsesRequest_TriggersOutboundCall_WithFoundryHostingSupplementAsync()
+    {
+        // Arrange: spin up a real ASP.NET Core TestServer that hosts an AIAgent backed by MEAI's
+        // OpenAIResponsesChatClient → ProjectResponsesClient → fake HTTP transport. This is the
+        // exact production stack minus the network: the only thing not real is the wire transport.
+        await this.StartHostedServerAsync();
+
+        // Act: send an inbound /openai/v1/responses request as the Foundry runtime would.
+        using var inboundRequest = new HttpRequestMessage(HttpMethod.Post, "/responses")
+        {
+            Content = new StringContent(InboundResponsesRequestJson(), Encoding.UTF8, "application/json"),
+        };
+        using var inboundResponse = await this._inboundClient!.SendAsync(inboundRequest);
+        var inboundBody = await inboundResponse.Content.ReadAsStringAsync();
+
+        // Assert: at least one OUTBOUND request reached the fake transport, AND it carries the
+        // foundry-hosting/agent-framework-dotnet/{version} supplement on its User-Agent.
+        // (We don't care about the inbound response shape — only that the agent's call to MEAI
+        // triggered an outbound request whose UA reaches the sandbox boundary correctly.)
+        Assert.True(this._outboundHandler!.Requests.Count > 0,
+            $"Expected at least one outbound request. Inbound status: {(int)inboundResponse.StatusCode}, body: {inboundBody}");
+        var outbound = this._outboundHandler.Requests[0];
+        Assert.StartsWith(TestEndpoint, outbound.Uri);
+        Assert.Contains("MEAI/", outbound.UserAgent);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", outbound.UserAgent);
+    }
+
+    private async Task StartHostedServerAsync()
+    {
+        var builder = WebApplication.CreateBuilder();
+        builder.WebHost.UseTestServer();
+
+        // Build a real ChatClientAgent whose IChatClient is MEAI's OpenAIResponsesChatClient
+        // wrapping a ProjectResponsesClient backed by a fake HTTP handler. After AgentFrameworkResponseHandler
+        // resolves this agent, TryApplyUserAgent will swap the inner _responseClient with our wrapper.
+        this._outboundHandler = new RecordingHandler(MinimalResponseJson());
+#pragma warning disable CA5399
+        var outboundHttpClient = new HttpClient(this._outboundHandler);
+#pragma warning restore CA5399
+
+        var projectOptions = new ProjectResponsesClientOptions
+        {
+            Transport = new HttpClientPipelineTransport(outboundHttpClient),
+        };
+        var projectResponsesClient = new ProjectResponsesClient(
+            new Uri(TestEndpoint),
+            new FakeAuthenticationTokenProvider(),
+            projectOptions);
+
+        IChatClient chatClient = projectResponsesClient.AsIChatClient(Deployment);
+        AIAgent agent = new ChatClientAgent(chatClient);
+
+        builder.Services.AddFoundryResponses(agent);
+        builder.Services.AddLogging();
+
+        this._app = builder.Build();
+        this._app.MapFoundryResponses();
+
+        await this._app.StartAsync();
+
+        var testServer = this._app.Services.GetRequiredService<IServer>() as TestServer
+            ?? throw new InvalidOperationException("TestServer not found");
+
+        this._inboundClient = testServer.CreateClient();
+    }
+
+    private static string InboundResponsesRequestJson() => """
+        {
+          "model": "fake-deployment",
+          "input": [
+            {
+              "type": "message",
+              "id": "msg_1",
+              "status": "completed",
+              "role": "user",
+              "content": [{ "type": "input_text", "text": "Hello" }]
+            }
+          ]
+        }
+        """;
+
+    private static string MinimalResponseJson() => """
+        {
+          "id":"resp_1","object":"response","created_at":1700000000,"status":"completed",
+          "model":"fake","output":[],"usage":{"input_tokens":1,"output_tokens":1,"total_tokens":2}
+        }
+        """;
+
+    private sealed class RecordingHandler : HttpClientHandler
+    {
+        private readonly string _body;
+        public List<RecordedRequest> Requests { get; } = [];
+
+        public RecordingHandler(string body)
+        {
+            this._body = body;
+        }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            string ua = request.Headers.TryGetValues("User-Agent", out var values)
+                ? string.Join(",", values)
+                : "(none)";
+            this.Requests.Add(new RecordedRequest(request.RequestUri?.ToString() ?? "?", ua));
+
+            var resp = new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(this._body, Encoding.UTF8, "application/json"),
+                RequestMessage = request,
+            };
+            return Task.FromResult(resp);
+        }
+    }
+
+    private readonly record struct RecordedRequest(string Uri, string UserAgent);
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/InputConverterTests.cs

@@ -2,7 +2,6 @@
 
 using System;
 using System.Linq;
-using Azure.AI.AgentServer.Responses;
 using Azure.AI.AgentServer.Responses.Models;
 using Microsoft.Agents.AI.Foundry.Hosting;
 using Microsoft.Extensions.AI;
@@ -146,11 +145,7 @@ public class InputConverterTests
     [Fact]
     public void ConvertToChatOptions_SetsTemperatureAndTopP()
     {
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            temperature: 0.7,
-            topP: 0.9,
-            maxOutputTokens: 1000,
-            model: "gpt-4o");
+        var request = new CreateResponse { Temperature = 0.7, TopP = 0.9, MaxOutputTokens = 1000, Model = "gpt-4o" };
 
         var options = InputConverter.ConvertToChatOptions(request);
 
@@ -211,9 +206,9 @@ public class InputConverterTests
     }
 
     [Fact]
-    public void ConvertOutputItemsToMessages_FunctionToolCallOutputResource_ReturnsToolMessage()
+    public void ConvertOutputItemsToMessages_FunctionToolCallOutput_ReturnsToolMessage()
     {
-        var funcOutput = new FunctionToolCallOutputResource(
+        var funcOutput = new OutputItemFunctionToolCallOutput(
             callId: "call_def",
             output: BinaryData.FromString("result data"));
 
@@ -229,8 +224,7 @@ public class InputConverterTests
     [Fact]
     public void ConvertOutputItemsToMessages_ReasoningItem_ReturnsNull()
     {
-        var reasoning = AzureAIAgentServerResponsesModelFactory.OutputItemReasoningItem(
-            id: "reason_001");
+        var reasoning = new OutputItemReasoningItem("reason_001", []);
 
         var messages = InputConverter.ConvertOutputItemsToMessages([reasoning]);
 
@@ -661,7 +655,7 @@ public class InputConverterTests
     [Fact]
     public void ConvertToChatOptions_ModelId_NotSetFromRequest()
     {
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "my-model");
+        var request = new CreateResponse { Model = "my-model" };
 
         var options = InputConverter.ConvertToChatOptions(request);
 

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/OutputConverterTests.cs

@@ -20,7 +20,7 @@ public class OutputConverterTests
     private static (ResponseEventStream stream, Mock<ResponseContext> mockContext) CreateTestStream()
     {
         var mockContext = new Mock<ResponseContext>("resp_" + new string('0', 46)) { CallBase = true };
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test-model");
+        var request = new CreateResponse { Model = "test-model" };
         var stream = new ResponseEventStream(mockContext.Object, request);
         return (stream, mockContext);
     }

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/ServiceCollectionExtensionsTests.cs

@@ -4,8 +4,10 @@ using System;
 using System.Linq;
 using Azure.AI.AgentServer.Responses;
 using Microsoft.Agents.AI.Foundry.Hosting;
+using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 using Moq;
+using OpenAI.Responses;
 
 namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
 
@@ -93,4 +95,45 @@ public class ServiceCollectionExtensionsTests
 
         Assert.Same(instrumented, result);
     }
+
+    [Fact]
+    public void TryApplyUserAgent_AgentWithoutChatClient_NoOp()
+    {
+        // Arrange: agent.GetService<IChatClient>() returns null.
+        var mockAgent = new Mock<AIAgent>();
+
+        // Act
+        var result = FoundryHostingExtensions.TryApplyUserAgent(mockAgent.Object);
+
+        // Assert
+        Assert.Same(mockAgent.Object, result);
+    }
+
+    [Fact]
+    public void TryApplyUserAgent_AgentWithNonMeaiChatClient_NoOp()
+    {
+        // Arrange: chat client that does not return MEAI's OpenAIResponsesChatClient via GetService.
+        var mockChatClient = new Mock<IChatClient>();
+        mockChatClient.Setup(c => c.GetService(It.IsAny<Type>(), It.IsAny<object?>())).Returns(null!);
+
+        var mockAgent = new Mock<AIAgent>();
+        mockAgent.Setup(a => a.GetService(typeof(IChatClient), It.IsAny<object?>())).Returns(mockChatClient.Object);
+
+        // Act
+        var result = FoundryHostingExtensions.TryApplyUserAgent(mockAgent.Object);
+
+        // Assert
+        Assert.Same(mockAgent.Object, result);
+    }
+
+    [Fact]
+    public void MeaiOpenAIResponsesChatClient_TypeFullName_ReflectionGuard()
+    {
+        // Guards the polyfill's reflection target type-name.
+        var meaiType = typeof(MicrosoftExtensionsAIResponsesExtensions).Assembly
+            .GetType("Microsoft.Extensions.AI.OpenAIResponsesChatClient");
+        Assert.NotNull(meaiType);
+        Assert.True(typeof(IChatClient).IsAssignableFrom(meaiType!),
+            $"Expected MEAI {meaiType!.FullName} to implement IChatClient.");
+    }
 }

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/UserAgentMiddlewareTests.cs

@@ -1,134 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Net.Http;
-using System.Text.RegularExpressions;
-using System.Threading.Tasks;
-using Microsoft.Agents.AI.Foundry.Hosting;
-using Microsoft.AspNetCore.Builder;
-using Microsoft.AspNetCore.Hosting.Server;
-using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.TestHost;
-using Microsoft.Extensions.DependencyInjection;
-using Moq;
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
-
-/// <summary>
-/// Tests for the <c>AgentFrameworkUserAgentMiddleware</c> registered by
-/// <see cref="FoundryHostingExtensions.MapFoundryResponses"/>.
-/// </summary>
-public sealed partial class UserAgentMiddlewareTests : IAsyncDisposable
-{
-    private const string VersionedUserAgentPattern = @"agent-framework-dotnet/\d+\.\d+\.\d+(-[\w.]+)?";
-
-    private WebApplication? _app;
-    private HttpClient? _httpClient;
-
-    public async ValueTask DisposeAsync()
-    {
-        this._httpClient?.Dispose();
-        if (this._app != null)
-        {
-            await this._app.DisposeAsync();
-        }
-    }
-
-    [Fact]
-    public async Task MapFoundryResponses_NoUserAgentHeader_SetsAgentFrameworkUserAgentAsync()
-    {
-        // Arrange
-        await this.CreateTestServerAsync();
-
-        using var request = new HttpRequestMessage(HttpMethod.Get, "/test-ua");
-
-        // Act
-        var response = await this._httpClient!.SendAsync(request);
-        var userAgent = await response.Content.ReadAsStringAsync();
-
-        // Assert
-        Assert.Matches(VersionedUserAgentPattern, userAgent);
-    }
-
-    [Fact]
-    public async Task MapFoundryResponses_WithExistingUserAgent_AppendsAgentFrameworkUserAgentAsync()
-    {
-        // Arrange
-        await this.CreateTestServerAsync();
-
-        using var request = new HttpRequestMessage(HttpMethod.Get, "/test-ua");
-        request.Headers.TryAddWithoutValidation("User-Agent", "MyApp/1.0");
-
-        // Act
-        var response = await this._httpClient!.SendAsync(request);
-        var userAgent = await response.Content.ReadAsStringAsync();
-
-        // Assert
-        Assert.StartsWith("MyApp/1.0", userAgent);
-        Assert.Matches(VersionedUserAgentPattern, userAgent);
-    }
-
-    [Fact]
-    public async Task MapFoundryResponses_AlreadyContainsUserAgent_DoesNotDuplicateAsync()
-    {
-        // Arrange
-        await this.CreateTestServerAsync();
-
-        // First request to capture the actual middleware-generated value
-        using var firstRequest = new HttpRequestMessage(HttpMethod.Get, "/test-ua");
-        var firstResponse = await this._httpClient!.SendAsync(firstRequest);
-        var middlewareValue = await firstResponse.Content.ReadAsStringAsync();
-
-        // Act: send a second request that already contains the middleware value
-        using var secondRequest = new HttpRequestMessage(HttpMethod.Get, "/test-ua");
-        secondRequest.Headers.TryAddWithoutValidation("User-Agent", $"MyApp/2.0 {middlewareValue}");
-        var secondResponse = await this._httpClient!.SendAsync(secondRequest);
-        var userAgent = await secondResponse.Content.ReadAsStringAsync();
-
-        // Assert: should remain unchanged (no duplication)
-        Assert.Equal($"MyApp/2.0 {middlewareValue}", userAgent);
-        Assert.Single(VersionedUserAgentRegex().Matches(userAgent));
-    }
-
-    [Fact]
-    public async Task MapFoundryResponses_UserAgentValue_ContainsVersionAsync()
-    {
-        // Arrange
-        await this.CreateTestServerAsync();
-
-        using var request = new HttpRequestMessage(HttpMethod.Get, "/test-ua");
-
-        // Act
-        var response = await this._httpClient!.SendAsync(request);
-        var userAgent = await response.Content.ReadAsStringAsync();
-
-        // Assert: should match "agent-framework-dotnet/x.y.z" pattern
-        Assert.Matches(VersionedUserAgentPattern, userAgent);
-    }
-
-    private async Task CreateTestServerAsync()
-    {
-        var builder = WebApplication.CreateBuilder();
-        builder.WebHost.UseTestServer();
-
-        var mockAgent = new Mock<AIAgent>();
-        builder.Services.AddFoundryResponses(mockAgent.Object);
-
-        this._app = builder.Build();
-        this._app.MapFoundryResponses();
-
-        // Test endpoint that echoes the User-Agent header after middleware processing
-        this._app.MapGet("/test-ua", (HttpContext ctx) =>
-            Results.Text(ctx.Request.Headers.UserAgent.ToString()));
-
-        await this._app.StartAsync();
-
-        var testServer = this._app.Services.GetRequiredService<IServer>() as TestServer
-            ?? throw new InvalidOperationException("TestServer not found");
-
-        this._httpClient = testServer.CreateClient();
-    }
-
-    [GeneratedRegex(VersionedUserAgentPattern)]
-    private static partial Regex VersionedUserAgentRegex();
-}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/WorkflowIntegrationTests.cs

@@ -160,9 +160,7 @@ public class WorkflowIntegrationTests
         var sp = services.BuildServiceProvider();
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(
-            model: "test",
-            agentReference: new AgentReference("my-workflow"));
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("my-workflow") };
         request.Input = CreateUserInput("Test keyed workflow");
         var mockContext = CreateMockContext();
 
@@ -363,7 +361,7 @@ public class WorkflowIntegrationTests
         var sp = services.BuildServiceProvider();
 
         var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test");
+        var request = new CreateResponse { Model = "test" };
         request.Input = CreateUserInput(userMessage);
         var mockContext = CreateMockContext();
 
@@ -393,7 +391,7 @@ public class WorkflowIntegrationTests
     private static (ResponseEventStream stream, Mock<ResponseContext> mockContext) CreateTestStream()
     {
         var mockContext = new Mock<ResponseContext>("resp_" + new string('0', 46)) { CallBase = true };
-        var request = AzureAIAgentServerResponsesModelFactory.CreateResponse(model: "test-model");
+        var request = new CreateResponse { Model = "test-model" };
         var stream = new ResponseEventStream(mockContext.Object, request);
         return (stream, mockContext);
     }

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Microsoft.Agents.AI.Foundry.UnitTests.csproj

@@ -10,7 +10,7 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'">
-    <PackageReference Include="Azure.AI.Projects" />
+    <PackageReference Include="Azure.AI.Projects" VersionOverride="2.1.0-beta.1" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp'">
@@ -34,7 +34,7 @@
     <ProjectReference Include="..\..\src\Microsoft.Agents.AI.Foundry.Hosting\Microsoft.Agents.AI.Foundry.Hosting.csproj" />
   </ItemGroup>
 
-  <!-- Evaluation tests require net8.0+ (MEAI.Evaluation does not support legacy TFMs) -->
+  <!-- FoundryEval tests require net8.0+ (MEAI.Evaluation does not support legacy TFMs) -->
   <ItemGroup Condition="!$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net8.0'))">
     <Compile Remove="FoundryEvalConverterTests.cs" />
     <Compile Remove="FoundryEvalsTests.cs" />
@@ -50,6 +50,15 @@
     <None Update="TestData\OpenAIDefaultResponse.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>
+    <None Update="TestData\ToolboxRecordResponse.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
+    <None Update="TestData\ToolboxVersionResponse.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
+    <None Update="TestData\ToolboxVersionWithDecorationFields.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 
 </Project>

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/RequestOptionsExtensionsTests.cs

@@ -0,0 +1,115 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.ClientModel.Primitives;
+using System.Net;
+using System.Net.Http;
+using System.Reflection;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.Agents.AI.Foundry.UnitTests;
+
+/// <summary>
+/// Verifies the per-call <c>MeaiUserAgentPolicy</c> exposed via
+/// <see cref="RequestOptionsExtensions.UserAgentPolicy"/>. The policy is reachable through the
+/// public <see cref="FoundryAgent"/> constructors (which add it to the internally-built
+/// <see cref="Azure.AI.Projects.AIProjectClient"/>'s pipeline), so its behavior is part of the
+/// public API surface.
+/// </summary>
+public sealed class RequestOptionsExtensionsTests
+{
+    [Fact]
+    public async Task MeaiUserAgentPolicy_AddsMeaiSegment_ToOutgoingRequestAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler();
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var pipeline = ClientPipeline.Create(
+            new ClientPipelineOptions { Transport = new HttpClientPipelineTransport(httpClient) },
+            perCallPolicies: [RequestOptionsExtensions.UserAgentPolicy],
+            perTryPolicies: default,
+            beforeTransportPolicies: default);
+
+        // Act
+        var message = pipeline.CreateMessage();
+        message.Request.Method = "POST";
+        message.Request.Uri = new System.Uri("https://example.test/anything");
+        await pipeline.SendAsync(message);
+
+        // Assert
+        Assert.Equal(1, handler.Count);
+        Assert.NotNull(handler.LastUserAgent);
+        Assert.Contains("MEAI/", handler.LastUserAgent);
+    }
+
+    [Fact]
+    public async Task MeaiUserAgentPolicy_DoesNotAddFoundryHostingSegmentAsync()
+    {
+        // Arrange
+        using var handler = new RecordingHandler();
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(handler);
+#pragma warning restore CA5399
+        var pipeline = ClientPipeline.Create(
+            new ClientPipelineOptions { Transport = new HttpClientPipelineTransport(httpClient) },
+            perCallPolicies: [RequestOptionsExtensions.UserAgentPolicy],
+            perTryPolicies: default,
+            beforeTransportPolicies: default);
+
+        // Act
+        var message = pipeline.CreateMessage();
+        message.Request.Method = "POST";
+        message.Request.Uri = new System.Uri("https://example.test/anything");
+        await pipeline.SendAsync(message);
+
+        // Assert: the policy is MEAI-only; the foundry-hosting supplement is added elsewhere
+        // (by the polyfill DelegatingResponsesClient → HostedAgentUserAgentPolicy).
+        Assert.NotNull(handler.LastUserAgent);
+        Assert.DoesNotContain("foundry-hosting/agent-framework-dotnet", handler.LastUserAgent);
+    }
+
+    [Fact]
+    public void UserAgentPolicy_ExposesSingletonInstance()
+    {
+        // Two reads of the static property must return the same instance — the policy is stateless and shared.
+        var first = RequestOptionsExtensions.UserAgentPolicy;
+        var second = RequestOptionsExtensions.UserAgentPolicy;
+        Assert.Same(first, second);
+    }
+
+    [Fact]
+    public void MeaiUserAgentPolicy_ValueIncludesAFFoundryAssemblyVersion_ReflectionGuard()
+    {
+        // The policy emits "MEAI/{Microsoft.Agents.AI.Foundry assembly InformationalVersion}".
+        // If the assembly metadata stops being readable, the policy falls back to "MEAI" without a version,
+        // which is a measurable telemetry regression.
+        var attr = typeof(RequestOptionsExtensions).Assembly
+            .GetCustomAttribute<AssemblyInformationalVersionAttribute>();
+        Assert.NotNull(attr);
+        Assert.False(string.IsNullOrEmpty(attr!.InformationalVersion));
+    }
+
+    private sealed class RecordingHandler : HttpClientHandler
+    {
+        public int Count { get; private set; }
+        public string? LastUserAgent { get; private set; }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            this.Count++;
+            this.LastUserAgent = request.Headers.TryGetValues("User-Agent", out var values)
+                ? string.Join(",", values)
+                : null;
+
+            var resp = new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent("{}", Encoding.UTF8, "application/json"),
+                RequestMessage = request,
+            };
+            return Task.FromResult(resp);
+        }
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/TestData/ToolboxRecordResponse.json

@@ -0,0 +1,5 @@
+{
+  "id": "tbx-123",
+  "name": "research_tools",
+  "default_version": "v5"
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/TestData/ToolboxVersionResponse.json

@@ -0,0 +1,11 @@
+{
+  "metadata": {},
+  "id": "tbv-research_tools-v5",
+  "name": "research_tools",
+  "version": "v5",
+  "description": "Example research toolbox",
+  "created_at": 1775779200,
+  "tools": [
+    { "type": "code_interpreter" }
+  ]
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/TestData/ToolboxVersionWithDecorationFields.json

@@ -0,0 +1,11 @@
+{
+  "metadata": {},
+  "id": "tbv-dirty-v1",
+  "name": "dirty_toolbox",
+  "version": "v1",
+  "description": "Toolbox with decoration fields on tools",
+  "created_at": 1775779200,
+  "tools": [
+    { "type": "code_interpreter", "name": "code_interpreter", "description": "Execute Python code" }
+  ]
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/TestDataUtil.cs

@@ -14,6 +14,9 @@ internal static class TestDataUtil
     private static readonly string s_agentResponseJson = File.ReadAllText("TestData/AgentResponse.json");
     private static readonly string s_agentVersionResponseJson = File.ReadAllText("TestData/AgentVersionResponse.json");
     private static readonly string s_openAIDefaultResponseJson = File.ReadAllText("TestData/OpenAIDefaultResponse.json");
+    private static readonly string s_toolboxRecordResponseJson = File.ReadAllText("TestData/ToolboxRecordResponse.json");
+    private static readonly string s_toolboxVersionResponseJson = File.ReadAllText("TestData/ToolboxVersionResponse.json");
+    private static readonly string s_toolboxVersionWithDecorationFieldsJson = File.ReadAllText("TestData/ToolboxVersionWithDecorationFields.json");
 
     private const string AgentDefinitionPlaceholder = "\"agent-definition-placeholder\"";
 
@@ -162,4 +165,19 @@ internal static class TestDataUtil
         }
         return json;
     }
+
+    /// <summary>
+    /// Gets the toolbox record response JSON.
+    /// </summary>
+    public static string GetToolboxRecordResponseJson() => s_toolboxRecordResponseJson;
+
+    /// <summary>
+    /// Gets the toolbox version response JSON.
+    /// </summary>
+    public static string GetToolboxVersionResponseJson() => s_toolboxVersionResponseJson;
+
+    /// <summary>
+    /// Gets the toolbox version response JSON with decoration fields on tools.
+    /// </summary>
+    public static string GetToolboxVersionWithDecorationFieldsJson() => s_toolboxVersionWithDecorationFieldsJson;
 }

dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/A2AAgentHandlerTests.cs

@@ -586,6 +586,457 @@ public sealed class A2AAgentHandlerTests
 
 #pragma warning restore MEAI001
 
+    /// <summary>
+    /// Verifies that in streaming mode, each update from RunStreamingAsync produces a message event.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_EnqueuesMessageForEachUpdateAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk 1") { ResponseId = "r1" },
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk 2") { ResponseId = "r2" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Assert.Equal(2, events.Messages.Count);
+        Assert.Equal("chunk 1", events.Messages[0].Parts![0].Text);
+        Assert.Equal("chunk 2", events.Messages[1].Parts![0].Text);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when metadata is present, options with AdditionalProperties
+    /// are passed to RunStreamingAsync.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WithMetadata_PassesOptionsWithAdditionalPropertiesAsync()
+    {
+        // Arrange
+        AgentRunOptions? capturedOptions = null;
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMockWithOptionsCapture(
+            options => capturedOptions = options));
+
+        // Act
+        await InvokeExecuteAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] },
+            Metadata = new Dictionary<string, JsonElement>
+            {
+                ["key1"] = JsonSerializer.SerializeToElement("value1")
+            }
+        });
+
+        // Assert
+        Assert.NotNull(capturedOptions);
+        Assert.NotNull(capturedOptions.AdditionalProperties);
+        Assert.Equal("value1", capturedOptions.AdditionalProperties["key1"]?.ToString());
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when metadata is null, null options are passed to RunStreamingAsync.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WithNullMetadata_PassesNullOptionsAsync()
+    {
+        // Arrange
+        AgentRunOptions? capturedOptions = null;
+        bool optionsCaptured = false;
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMockWithOptionsCapture(
+            options => { capturedOptions = options; optionsCaptured = true; }));
+
+        // Act
+        await InvokeExecuteAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Assert.True(optionsCaptured);
+        Assert.Null(capturedOptions);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, ReferenceTaskIds throws NotSupportedException.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WithReferenceTaskIds_ThrowsNotSupportedExceptionAsync()
+    {
+        // Arrange
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock([]));
+
+        // Act & Assert
+        var eventQueue = new AgentEventQueue();
+        await Assert.ThrowsAsync<NotSupportedException>(() =>
+            handler.ExecuteAsync(
+                new RequestContext
+                {
+                    StreamingResponse = true,
+                    TaskId = "",
+                    ContextId = "ctx",
+                    Message = new Message
+                    {
+                        MessageId = "test-id",
+                        Role = Role.User,
+                        Parts = [new Part { Text = "Hello" }],
+                        ReferenceTaskIds = ["other-task-id"]
+                    }
+                },
+                eventQueue,
+                CancellationToken.None));
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when ContextId is null, a new one is generated.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WhenContextIdIsNull_GeneratesContextIdAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "Reply") { ResponseId = "r1" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = null!,
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.NotNull(message.ContextId);
+        Assert.NotEmpty(message.ContextId);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, the provided ContextId is used in the response.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_UsesProvidedContextIdAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "Reply") { ResponseId = "r1" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "my-streaming-ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.Equal("my-streaming-ctx", message.ContextId);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when Message is null, the handler succeeds with empty messages.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WhenMessageIsNull_SucceedsWithEmptyMessagesAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "Reply") { ResponseId = "r1" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = null!
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.Equal("ctx", message.ContextId);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, the ResponseId from the update is used as the MessageId in the response.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_ResponseIdIsUsedAsMessageIdAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = "resp-42" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.Equal("resp-42", message.MessageId);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when ResponseId is null, a MessageId is still generated.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WhenResponseIdIsNull_GeneratesMessageIdAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = null }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.NotNull(message.MessageId);
+        Assert.NotEmpty(message.MessageId);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when the update has AdditionalProperties, the message has metadata.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WithResponseAdditionalProperties_ReturnsMessageWithMetadataAsync()
+    {
+        // Arrange
+        AdditionalPropertiesDictionary additionalProps = new()
+        {
+            ["streamKey"] = "streamValue"
+        };
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = "r1", AdditionalProperties = additionalProps }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.NotNull(message.Metadata);
+        Assert.True(message.Metadata.ContainsKey("streamKey"));
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when the update has null AdditionalProperties, the message has null metadata.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WithNullAdditionalProperties_ReturnsMessageWithNullMetadataAsync()
+    {
+        // Arrange
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = "r1", AdditionalProperties = null }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates));
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Message message = Assert.Single(events.Messages);
+        Assert.Null(message.Metadata);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, the session is saved after all updates are processed.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_SavesSessionAfterProcessingAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.IsAny<string>(),
+                It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.IsAny<string>(),
+                It.IsAny<AgentSession>(),
+                It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        AgentResponseUpdate[] updates =
+        [
+            new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = "r1" }
+        ];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates), agentSessionStore: mockSessionStore.Object);
+
+        // Act
+        await InvokeExecuteAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx-stream",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert - verify session was saved
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx-stream"),
+                It.IsAny<AgentSession>(),
+                It.IsAny<CancellationToken>()),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that in streaming mode, when RunStreamingAsync yields no updates,
+    /// no messages are enqueued and the session is still saved.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WhenNoUpdates_EnqueuesNoMessagesAndSavesSessionAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.IsAny<string>(),
+                It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.IsAny<string>(),
+                It.IsAny<AgentSession>(),
+                It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock([]), agentSessionStore: mockSessionStore.Object);
+
+        // Act
+        var events = await CollectEventsAsync(handler, new RequestContext
+        {
+            StreamingResponse = true,
+            TaskId = "",
+            ContextId = "ctx",
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+        });
+
+        // Assert
+        Assert.Empty(events.Messages);
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx"),
+                It.IsAny<AgentSession>(),
+                It.IsAny<CancellationToken>()),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that the CancellationToken is propagated to RunStreamingAsync in the streaming path.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_CancellationTokenIsPropagatedToRunStreamingAsync()
+    {
+        // Arrange
+        CancellationToken capturedToken = default;
+        using var cts = new CancellationTokenSource();
+
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock
+            .Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock
+            .Protected()
+            .Setup<IAsyncEnumerable<AgentResponseUpdate>>("RunCoreStreamingAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .Callback<IEnumerable<ChatMessage>, AgentSession?, AgentRunOptions?, CancellationToken>(
+                (_, _, _, ct) => capturedToken = ct)
+            .Returns(() => ToAsyncEnumerableAsync([new AgentResponseUpdate(ChatRole.Assistant, "reply") { ResponseId = "r1" }]));
+
+        A2AAgentHandler handler = CreateHandler(agentMock);
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        await handler.ExecuteAsync(
+            new RequestContext
+            {
+                TaskId = "",
+                ContextId = "ctx",
+                StreamingResponse = true,
+                Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+            },
+            eventQueue,
+            cts.Token);
+        eventQueue.Complete(null);
+
+        // Assert
+        Assert.Equal(cts.Token, capturedToken);
+    }
+
     /// <summary>
     /// Verifies that when no session store is provided, the handler uses InMemoryAgentSessionStore
     /// and can execute successfully.
@@ -821,6 +1272,308 @@ public sealed class A2AAgentHandlerTests
         Assert.True(capturedOptions.AllowBackgroundResponses);
     }
 
+    /// <summary>
+    /// Verifies that in the non-streaming path, SaveSessionAsync is called with
+    /// CancellationToken.None even when RunAsync throws an exception.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_NonStreaming_WhenRunAsyncThrows_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock.Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock.Protected()
+            .Setup<Task<AgentResponse>>("RunCoreAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .ThrowsAsync(new InvalidOperationException("Agent failed"));
+
+        using var cts = new CancellationTokenSource();
+        A2AAgentHandler handler = CreateHandler(agentMock, agentSessionStore: mockSessionStore.Object);
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        await Assert.ThrowsAsync<InvalidOperationException>(() =>
+            handler.ExecuteAsync(
+                new RequestContext
+                {
+                    TaskId = "", ContextId = "ctx", StreamingResponse = false,
+                    Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+                },
+                eventQueue,
+                cts.Token));
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None despite the exception
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that in the streaming path, SaveSessionAsync is called with
+    /// CancellationToken.None even when RunStreamingAsync throws an exception.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_WhenRunStreamingAsyncThrows_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock.Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock.Protected()
+            .Setup<IAsyncEnumerable<AgentResponseUpdate>>("RunCoreStreamingAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .Returns(() => ToThrowingAsyncEnumerableAsync(new InvalidOperationException("Stream failed")));
+
+        using var cts = new CancellationTokenSource();
+        A2AAgentHandler handler = CreateHandler(agentMock, agentSessionStore: mockSessionStore.Object);
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        await Assert.ThrowsAsync<InvalidOperationException>(() =>
+            handler.ExecuteAsync(
+                new RequestContext
+                {
+                    TaskId = "", ContextId = "ctx-stream", StreamingResponse = true,
+                    Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+                },
+                eventQueue,
+                cts.Token));
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None despite the exception
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx-stream"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that on the continuation path, SaveSessionAsync is called with
+    /// CancellationToken.None even when RunAsync throws an exception.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_OnContinuation_WhenRunAsyncThrows_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock.Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock.Protected()
+            .Setup<Task<AgentResponse>>("RunCoreAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .ThrowsAsync(new InvalidOperationException("Agent failed"));
+
+        using var cts = new CancellationTokenSource();
+        A2AAgentHandler handler = CreateHandler(agentMock, agentSessionStore: mockSessionStore.Object);
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        var events = new EventCollector();
+        var readerTask = ReadEventsAsync(eventQueue, events);
+        await Assert.ThrowsAsync<InvalidOperationException>(() =>
+            handler.ExecuteAsync(
+                new RequestContext
+                {
+                    StreamingResponse = false,
+                    TaskId = "task-1", ContextId = "ctx-cont",
+                    Message = new Message { MessageId = "empty", Role = Role.User, Parts = [] },
+                    Task = new AgentTask { Id = "task-1", ContextId = "ctx-cont", History = [new Message { Role = Role.User, Parts = [new Part { Text = "Hello" }] }] }
+                },
+                eventQueue,
+                cts.Token));
+        eventQueue.Complete(null);
+        await readerTask;
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None despite the exception
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx-cont"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that in the non-streaming path, SaveSessionAsync is called with
+    /// CancellationToken.None rather than the caller's cancellation token.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_NonStreaming_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        AgentResponse response = new([new ChatMessage(ChatRole.Assistant, "Reply")]);
+        A2AAgentHandler handler = CreateHandler(CreateAgentMockWithResponse(response), agentSessionStore: mockSessionStore.Object);
+
+        using var cts = new CancellationTokenSource();
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        await handler.ExecuteAsync(
+            new RequestContext
+            {
+                TaskId = "", ContextId = "ctx", StreamingResponse = false,
+                Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+            },
+            eventQueue,
+            cts.Token);
+        eventQueue.Complete(null);
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None, not the caller's token
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that in the streaming path, SaveSessionAsync is called with
+    /// CancellationToken.None rather than the caller's cancellation token.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_Streaming_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        AgentResponseUpdate[] updates = [new AgentResponseUpdate(ChatRole.Assistant, "chunk") { ResponseId = "r1" }];
+        A2AAgentHandler handler = CreateHandler(CreateStreamingAgentMock(updates), agentSessionStore: mockSessionStore.Object);
+
+        using var cts = new CancellationTokenSource();
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        await handler.ExecuteAsync(
+            new RequestContext
+            {
+                TaskId = "", ContextId = "ctx-stream", StreamingResponse = true,
+                Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] }
+            },
+            eventQueue,
+            cts.Token);
+        eventQueue.Complete(null);
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None, not the caller's token
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx-stream"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
+    /// <summary>
+    /// Verifies that on the continuation path, SaveSessionAsync is called with
+    /// CancellationToken.None rather than the caller's cancellation token.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_OnContinuation_SavesSessionWithUncancelledTokenAsync()
+    {
+        // Arrange
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        mockSessionStore
+            .Setup(x => x.GetSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new TestAgentSession());
+        mockSessionStore
+            .Setup(x => x.SaveSessionAsync(It.IsAny<AIAgent>(), It.IsAny<string>(), It.IsAny<AgentSession>(), It.IsAny<CancellationToken>()))
+            .Returns(ValueTask.CompletedTask);
+
+        AgentResponse response = new([new ChatMessage(ChatRole.Assistant, "Done!")]);
+        A2AAgentHandler handler = CreateHandler(CreateAgentMockWithResponse(response), agentSessionStore: mockSessionStore.Object);
+
+        using var cts = new CancellationTokenSource();
+
+        // Act
+        var eventQueue = new AgentEventQueue();
+        var events = new EventCollector();
+        var readerTask = ReadEventsAsync(eventQueue, events);
+        await handler.ExecuteAsync(
+            new RequestContext
+            {
+                StreamingResponse = false,
+                TaskId = "task-1", ContextId = "ctx-cont",
+                Message = new Message { MessageId = "empty", Role = Role.User, Parts = [] },
+                Task = new AgentTask { Id = "task-1", ContextId = "ctx-cont", History = [new Message { Role = Role.User, Parts = [new Part { Text = "Hello" }] }] }
+            },
+            eventQueue,
+            cts.Token);
+        eventQueue.Complete(null);
+        await readerTask;
+
+        // Assert - SaveSessionAsync was called with CancellationToken.None, not the caller's token
+        mockSessionStore.Verify(
+            x => x.SaveSessionAsync(
+                It.IsAny<AIAgent>(),
+                It.Is<string>(s => s == "ctx-cont"),
+                It.IsAny<AgentSession>(),
+                It.Is<CancellationToken>(ct => ct == CancellationToken.None)),
+            Times.Once);
+    }
+
     private static A2AAgentHandler CreateHandler(
         Mock<AIAgent> agentMock,
         AgentRunMode? runMode = null,
@@ -905,6 +1658,68 @@ public sealed class A2AAgentHandlerTests
         return agentMock;
     }
 
+    private static Mock<AIAgent> CreateStreamingAgentMock(IEnumerable<AgentResponseUpdate> updates)
+    {
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock
+            .Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock
+            .Protected()
+            .Setup<IAsyncEnumerable<AgentResponseUpdate>>("RunCoreStreamingAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .Returns(() => ToAsyncEnumerableAsync(updates));
+
+        return agentMock;
+    }
+
+    private static Mock<AIAgent> CreateStreamingAgentMockWithOptionsCapture(
+        Action<AgentRunOptions?> optionsCallback)
+    {
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns("TestAgent");
+        agentMock
+            .Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock
+            .Protected()
+            .Setup<IAsyncEnumerable<AgentResponseUpdate>>("RunCoreStreamingAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .Callback<IEnumerable<ChatMessage>, AgentSession?, AgentRunOptions?, CancellationToken>(
+                (_, _, options, _) => optionsCallback(options))
+            .Returns(() => ToAsyncEnumerableAsync([new AgentResponseUpdate(ChatRole.Assistant, "reply") { ResponseId = "r1" }]));
+
+        return agentMock;
+    }
+
+    private static async IAsyncEnumerable<T> ToAsyncEnumerableAsync<T>(IEnumerable<T> items)
+    {
+        await Task.Yield();
+        foreach (var item in items)
+        {
+            yield return item;
+        }
+    }
+
+    private static async IAsyncEnumerable<AgentResponseUpdate> ToThrowingAsyncEnumerableAsync(Exception exception)
+    {
+        await Task.Yield();
+        throw exception;
+
+#pragma warning disable CS0162 // Unreachable code detected - yield is required for async iterator
+        yield break;
+#pragma warning restore CS0162
+    }
+
     private static async Task InvokeExecuteAsync(A2AAgentHandler handler, RequestContext context)
     {
         var eventQueue = new AgentEventQueue();

dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/Converters/MessageConverterTests.cs

@@ -147,4 +147,67 @@ public class MessageConverterTests
         Assert.Equal("First message", result[0].Text);
         Assert.Equal("Second message", result[1].Text);
     }
+
+    [Fact]
+    public void ToParts_AgentResponseUpdate_WithNoContents_ReturnsEmptyList()
+    {
+        // Arrange
+        var update = new AgentResponseUpdate();
+
+        // Act
+        var result = update.ToParts();
+
+        // Assert
+        Assert.NotNull(result);
+        Assert.Empty(result);
+    }
+
+    [Fact]
+    public void ToParts_AgentResponseUpdate_WithTextContent_ReturnsTextPart()
+    {
+        // Arrange
+        var update = new AgentResponseUpdate(ChatRole.Assistant, "Hello from streaming!");
+
+        // Act
+        var result = update.ToParts();
+
+        // Assert
+        Assert.Single(result);
+        Assert.Equal("Hello from streaming!", result[0].Text);
+    }
+
+    [Fact]
+    public void ToParts_AgentResponseUpdate_WithMultipleContents_ReturnsAllParts()
+    {
+        // Arrange
+        var update = new AgentResponseUpdate(ChatRole.Assistant, [
+            new TextContent("First chunk"),
+            new TextContent("Second chunk")
+        ]);
+
+        // Act
+        var result = update.ToParts();
+
+        // Assert
+        Assert.Equal(2, result.Count);
+        Assert.Equal("First chunk", result[0].Text);
+        Assert.Equal("Second chunk", result[1].Text);
+    }
+
+    [Fact]
+    public void ToParts_AgentResponseUpdate_WithUnsupportedContent_FiltersOutNulls()
+    {
+        // Arrange - FunctionCallContent maps to null Part since it's not a supported A2A content type
+        var update = new AgentResponseUpdate(ChatRole.Assistant, [
+            new TextContent("Supported text"),
+            new FunctionCallContent("call-1", "myFunction")
+        ]);
+
+        // Act
+        var result = update.ToParts();
+
+        // Assert - only the text part should be returned
+        Assert.Single(result);
+        Assert.Equal("Supported text", result[0].Text);
+    }
 }

dotnet/tests/Microsoft.Agents.AI.Hosting.AzureFunctions.IntegrationTests/WorkflowSamplesValidation.cs

@@ -3,6 +3,7 @@
 using System.Diagnostics;
 using System.Reflection;
 using System.Text;
+using System.Text.Json;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 using ModelContextProtocol.Client;
@@ -125,6 +126,45 @@ public sealed class WorkflowSamplesValidation(ITestOutputHelper outputHelper) :
                 },
                 message: "OrderStatus workflow completed",
                 timeout: s_orchestrationTimeout);
+
+            // Test the CancelOrder workflow with x-ms-wait-for-response header
+            this._outputHelper.WriteLine("Starting CancelOrder workflow with x-ms-wait-for-response: true...");
+
+            using HttpRequestMessage waitRequest = new(HttpMethod.Post, cancelOrderUri);
+            waitRequest.Content = new StringContent("55555", Encoding.UTF8, "text/plain");
+            waitRequest.Headers.Add("x-ms-wait-for-response", "true");
+            using HttpResponseMessage waitResponse = await s_sharedHttpClient.SendAsync(waitRequest);
+
+            Assert.True(waitResponse.IsSuccessStatusCode, $"CancelOrder wait-for-response request failed with status: {waitResponse.StatusCode}");
+            string waitResponseText = await waitResponse.Content.ReadAsStringAsync();
+            this._outputHelper.WriteLine($"CancelOrder wait-for-response result: {waitResponseText}");
+
+            // The response should contain the workflow result (not just "started for CancelOrder")
+            Assert.DoesNotContain("Workflow orchestration started", waitResponseText);
+            Assert.Contains("55555", waitResponseText);
+
+            // Test the wait-for-response with Accept: application/json header
+            this._outputHelper.WriteLine("Starting CancelOrder workflow with x-ms-wait-for-response and Accept: application/json...");
+
+            using HttpRequestMessage jsonWaitRequest = new(HttpMethod.Post, cancelOrderUri);
+            jsonWaitRequest.Content = new StringContent("77777", Encoding.UTF8, "text/plain");
+            jsonWaitRequest.Headers.Add("x-ms-wait-for-response", "true");
+            jsonWaitRequest.Headers.Add("Accept", "application/json");
+
+            using CancellationTokenSource jsonWaitCts = new(s_orchestrationTimeout);
+            using HttpResponseMessage jsonWaitResponse = await s_sharedHttpClient.SendAsync(jsonWaitRequest, jsonWaitCts.Token);
+
+            Assert.True(jsonWaitResponse.IsSuccessStatusCode, $"CancelOrder JSON wait-for-response request failed with status: {jsonWaitResponse.StatusCode}");
+            string jsonWaitResponseText = await jsonWaitResponse.Content.ReadAsStringAsync();
+            this._outputHelper.WriteLine($"CancelOrder JSON wait-for-response result: {jsonWaitResponseText}");
+
+            using JsonDocument jsonDoc = JsonDocument.Parse(jsonWaitResponseText);
+            JsonElement root = jsonDoc.RootElement;
+            Assert.True(root.TryGetProperty("runId", out _), "JSON response missing 'runId' property");
+            Assert.True(root.TryGetProperty("workflowStatus", out JsonElement statusEl), "JSON response missing 'workflowStatus' property");
+            Assert.Equal("Completed", statusEl.GetString());
+            Assert.True(root.TryGetProperty("result", out JsonElement resultEl), "JSON response missing 'result' property");
+            Assert.Contains("77777", resultEl.GetString());
         });
     }
 

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentClassSkillTests.cs

@@ -8,7 +8,6 @@ using System.Reflection;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
@@ -128,8 +127,9 @@ public sealed class AgentClassSkillTests
         // Act — script with custom type deserialization
         var script = skill.Scripts![0];
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "test", MaxResults = 5 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
-        var scriptResult = await script.RunAsync(skill, args, CancellationToken.None);
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
+        var scriptResult = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.NotNull(scriptResult);
@@ -173,12 +173,14 @@ public sealed class AgentClassSkillTests
 
         // Act & Assert — static method
         var doWorkScript = skill.Scripts!.First(s => s.Name == "do-work");
-        var doWorkResult = await doWorkScript.RunAsync(skill, new AIFunctionArguments { ["input"] = "hello" }, CancellationToken.None);
+        using var doWorkDoc = JsonDocument.Parse("""{"input":"hello"}""");
+        var doWorkResult = await doWorkScript.RunAsync(skill, doWorkDoc.RootElement, null, CancellationToken.None);
         Assert.Equal("HELLO", doWorkResult?.ToString());
 
         // Act & Assert — instance method
         var appendScript = skill.Scripts!.First(s => s.Name == "append");
-        var appendResult = await appendScript.RunAsync(skill, new AIFunctionArguments { ["input"] = "test" }, CancellationToken.None);
+        using var appendDoc = JsonDocument.Parse("""{"input":"test"}""");
+        var appendResult = await appendScript.RunAsync(skill, appendDoc.RootElement, null, CancellationToken.None);
         Assert.Equal("test-suffix", appendResult?.ToString());
     }
 
@@ -367,7 +369,7 @@ public sealed class AgentClassSkillTests
         // Act & Assert — all scripts produce values
         foreach (var script in skill.Scripts!)
         {
-            var result = await script.RunAsync(skill, new AIFunctionArguments(), CancellationToken.None);
+            var result = await script.RunAsync(skill, null, null, CancellationToken.None);
             Assert.NotNull(result);
         }
     }
@@ -382,8 +384,9 @@ public sealed class AgentClassSkillTests
         // Act & Assert — script with custom JSO
         var script = skill.Scripts![0];
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "test", MaxResults = 3 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
-        var scriptResult = await script.RunAsync(skill, args, CancellationToken.None);
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
+        var scriptResult = await script.RunAsync(skill, args, null, CancellationToken.None);
         Assert.NotNull(scriptResult);
         Assert.Contains("test", scriptResult!.ToString()!);
         Assert.Contains("3", scriptResult!.ToString()!);
@@ -497,8 +500,9 @@ public sealed class AgentClassSkillTests
         var script = skill.Scripts!.First(s => s.Name == "Lookup");
         var jso = SkillTestJsonContext.Default.Options;
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "fallback", MaxResults = 7 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.NotNull(result);
@@ -531,8 +535,9 @@ public sealed class AgentClassSkillTests
         var script = skill.Scripts!.First(s => s.Name == "Lookup");
         var jso = SkillTestJsonContext.Default.Options;
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "explicit", MaxResults = 2 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.NotNull(result);

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentFileSkillScriptTests.cs

@@ -1,9 +1,9 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 
 namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
 
@@ -16,13 +16,13 @@ public sealed class AgentFileSkillScriptTests
     public async Task RunAsync_SkillIsNotAgentFileSkill_ThrowsInvalidOperationExceptionAsync()
     {
         // Arrange
-        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, AIFunctionArguments a, CancellationToken ct) => Task.FromResult<object?>("result");
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>("result");
         var script = CreateScript("test-script", "/path/to/script.py", RunnerAsync);
         var nonFileSkill = new TestAgentSkill("my-skill", "A skill", "Instructions.");
 
         // Act & Assert
         await Assert.ThrowsAsync<InvalidOperationException>(
-            () => script.RunAsync(nonFileSkill, new AIFunctionArguments(), CancellationToken.None));
+            () => script.RunAsync(nonFileSkill, null, null, CancellationToken.None));
     }
 
     [Fact]
@@ -30,7 +30,7 @@ public sealed class AgentFileSkillScriptTests
     {
         // Arrange
         var runnerCalled = false;
-        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, AIFunctionArguments args, CancellationToken ct)
+        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, JsonElement? args, IServiceProvider? sp, CancellationToken ct)
         {
             runnerCalled = true;
             return Task.FromResult<object?>("executed");
@@ -42,7 +42,7 @@ public sealed class AgentFileSkillScriptTests
             "/skills/my-skill");
 
         // Act
-        var result = await script.RunAsync(fileSkill, new AIFunctionArguments(), CancellationToken.None);
+        var result = await script.RunAsync(fileSkill, null, null, CancellationToken.None);
 
         // Assert
         Assert.True(runnerCalled);
@@ -55,7 +55,7 @@ public sealed class AgentFileSkillScriptTests
         // Arrange
         AgentFileSkill? capturedSkill = null;
         AgentFileSkillScript? capturedScript = null;
-        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, AIFunctionArguments args, CancellationToken ct)
+        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, JsonElement? args, IServiceProvider? sp, CancellationToken ct)
         {
             capturedSkill = skill;
             capturedScript = scriptArg;
@@ -68,7 +68,7 @@ public sealed class AgentFileSkillScriptTests
             "/skills/owner-skill");
 
         // Act
-        await script.RunAsync(fileSkill, new AIFunctionArguments(), CancellationToken.None);
+        await script.RunAsync(fileSkill, null, null, CancellationToken.None);
 
         // Assert
         Assert.Same(fileSkill, capturedSkill);
@@ -79,7 +79,7 @@ public sealed class AgentFileSkillScriptTests
     public void Script_HasCorrectNameAndPath()
     {
         // Arrange & Act
-        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, AIFunctionArguments a, CancellationToken ct) => Task.FromResult<object?>(null);
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>(null);
         var script = CreateScript("my-script", "/path/to/my-script.py", RunnerAsync);
 
         // Assert
@@ -87,10 +87,173 @@ public sealed class AgentFileSkillScriptTests
         Assert.Equal("/path/to/my-script.py", script.FullPath);
     }
 
+    [Fact]
+    public void ParametersSchema_ReturnsExpectedArraySchema()
+    {
+        // Arrange
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>(null);
+        var script = CreateScript("my-script", "/path/to/script.py", RunnerAsync);
+
+        // Act
+        var schema = script.ParametersSchema;
+
+        // Assert
+        Assert.NotNull(schema);
+        var raw = schema!.Value.GetRawText();
+        Assert.Contains("\"type\":\"array\"", raw);
+        Assert.Contains("\"items\":{\"type\":\"string\"}", raw);
+    }
+
+    [Fact]
+    public void Content_WithScripts_AppendsPerScriptEntries()
+    {
+        // Arrange
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>(null);
+        var script1 = CreateScript("build", "/scripts/build.sh", RunnerAsync);
+        var script2 = CreateScript("deploy", "/scripts/deploy.sh", RunnerAsync);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Original content",
+            "/skills/my-skill",
+            scripts: [script1, script2]);
+
+        // Act
+        var content = fileSkill.Content;
+
+        // Assert — content starts with original and appends per-script entries
+        Assert.StartsWith("Original content", content);
+        Assert.Contains("<scripts>", content);
+        Assert.Contains("<script name=\"build\">", content);
+        Assert.Contains("<script name=\"deploy\">", content);
+        Assert.Contains("<parameters_schema>", content);
+        Assert.Contains("</scripts>", content);
+    }
+
+    [Fact]
+    public void Content_WithoutScripts_ReturnsOriginalContent()
+    {
+        // Arrange
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Original content only",
+            "/skills/my-skill");
+
+        // Act
+        var content = fileSkill.Content;
+
+        // Assert
+        Assert.Equal("Original content only", content);
+    }
+
+    [Fact]
+    public void Content_WithScripts_IsCached()
+    {
+        // Arrange
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>(null);
+        var script = CreateScript("test", "/scripts/test.sh", RunnerAsync);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Content",
+            "/skills/my-skill",
+            scripts: [script]);
+
+        // Act
+        var content1 = fileSkill.Content;
+        var content2 = fileSkill.Content;
+
+        // Assert
+        Assert.Same(content1, content2);
+    }
+
+    [Fact]
+    public async Task RunAsync_ForwardsJsonArrayArgumentsToRunnerAsync()
+    {
+        // Arrange
+        JsonElement? capturedArgs = null;
+        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, JsonElement? args, IServiceProvider? sp, CancellationToken ct)
+        {
+            capturedArgs = args;
+            return Task.FromResult<object?>("done");
+        }
+        var script = CreateScript("array-test", "/scripts/test.sh", runnerAsync);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Content",
+            "/skills/my-skill");
+        using var arrayArgsDoc = JsonDocument.Parse("""["arg1","arg2","arg3"]""");
+        var arrayArgs = arrayArgsDoc.RootElement;
+
+        // Act
+        await script.RunAsync(fileSkill, arrayArgs, null, CancellationToken.None);
+
+        // Assert — the raw JSON array is forwarded unchanged
+        Assert.NotNull(capturedArgs);
+        Assert.Equal(JsonValueKind.Array, capturedArgs!.Value.ValueKind);
+        Assert.Equal("""["arg1","arg2","arg3"]""", capturedArgs.Value.GetRawText());
+    }
+
+    [Fact]
+    public async Task RunAsync_ForwardsServiceProviderToRunnerAsync()
+    {
+        // Arrange
+        IServiceProvider? capturedProvider = null;
+        Task<object?> runnerAsync(AgentFileSkill skill, AgentFileSkillScript scriptArg, JsonElement? args, IServiceProvider? sp, CancellationToken ct)
+        {
+            capturedProvider = sp;
+            return Task.FromResult<object?>("done");
+        }
+        var script = CreateScript("sp-test", "/scripts/test.sh", runnerAsync);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Content",
+            "/skills/my-skill");
+        var mockProvider = new TestServiceProvider();
+
+        // Act
+        await script.RunAsync(fileSkill, null, mockProvider, CancellationToken.None);
+
+        // Assert
+        Assert.Same(mockProvider, capturedProvider);
+    }
+
+    [Fact]
+    public async Task RunAsync_NoRunner_ThrowsInvalidOperationExceptionAsync()
+    {
+        // Arrange — create script without a runner
+        var script = CreateScript("no-runner", "/scripts/test.sh", runner: null);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Content",
+            "/skills/my-skill");
+
+        // Act & Assert
+        await Assert.ThrowsAsync<InvalidOperationException>(
+            () => script.RunAsync(fileSkill, null, null, CancellationToken.None));
+    }
+
+    [Fact]
+    public void Content_WithScripts_ContainsDefaultParametersSchema()
+    {
+        // Arrange
+        static Task<object?> RunnerAsync(AgentFileSkill s, AgentFileSkillScript sc, JsonElement? a, IServiceProvider? sp, CancellationToken ct) => Task.FromResult<object?>(null);
+        var script = CreateScript("test", "/scripts/test.sh", RunnerAsync);
+        var fileSkill = new AgentFileSkill(
+            new AgentSkillFrontmatter("my-skill", "A skill"),
+            "Original content",
+            "/skills/my-skill",
+            scripts: [script]);
+
+        // Act
+        var content = fileSkill.Content;
+
+        // Assert — the appended block contains the actual default schema from AgentFileSkillScript
+        Assert.Contains("""{"type":"array","items":{"type":"string"}}""", content);
+    }
+
     /// <summary>
     /// Helper to create an <see cref="AgentFileSkillScript"/> via reflection since the constructor is internal.
     /// </summary>
-    private static AgentFileSkillScript CreateScript(string name, string fullPath, AgentFileSkillScriptRunner executor)
+    private static AgentFileSkillScript CreateScript(string name, string fullPath, AgentFileSkillScriptRunner? runner)
     {
         var ctor = typeof(AgentFileSkillScript).GetConstructor(
             System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance,
@@ -98,6 +261,14 @@ public sealed class AgentFileSkillScriptTests
             [typeof(string), typeof(string), typeof(AgentFileSkillScriptRunner)],
             null) ?? throw new InvalidOperationException("Could not find internal constructor.");
 
-        return (AgentFileSkillScript)ctor.Invoke([name, fullPath, executor]);
+        return (AgentFileSkillScript)ctor.Invoke([name, fullPath, runner]);
+    }
+
+    /// <summary>
+    /// Minimal <see cref="IServiceProvider"/> for testing service forwarding.
+    /// </summary>
+    private sealed class TestServiceProvider : IServiceProvider
+    {
+        public object? GetService(Type serviceType) => null;
     }
 }

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentFileSkillsSourceScriptTests.cs

@@ -3,9 +3,9 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 
 namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
 
@@ -15,7 +15,7 @@ namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
 public sealed class AgentFileSkillsSourceScriptTests : IDisposable
 {
     private static readonly string[] s_rubyExtension = new[] { ".rb" };
-    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, ct) => Task.FromResult<object?>(null);
+    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, sp, ct) => Task.FromResult<object?>(null);
 
     private readonly string _testRoot;
 
@@ -139,7 +139,7 @@ public sealed class AgentFileSkillsSourceScriptTests : IDisposable
         var executorCalled = false;
         var source = new AgentFileSkillsSource(
             this._testRoot,
-            (skill, script, args, ct) =>
+            (skill, script, args, sp, ct) =>
             {
                 executorCalled = true;
                 Assert.Equal("exec-skill", skill.Frontmatter.Name);
@@ -150,7 +150,7 @@ public sealed class AgentFileSkillsSourceScriptTests : IDisposable
 
         // Act
         var skills = await source.GetSkillsAsync(CancellationToken.None);
-        var scriptResult = await skills[0].Scripts![0].RunAsync(skills[0], new AIFunctionArguments(), CancellationToken.None);
+        var scriptResult = await skills[0].Scripts![0].RunAsync(skills[0], null, null, CancellationToken.None);
 
         // Assert
         Assert.True(executorCalled);
@@ -178,7 +178,7 @@ public sealed class AgentFileSkillsSourceScriptTests : IDisposable
         var script = skills[0].Scripts![0];
 
         // Assert — running the script throws because no runner was provided
-        await Assert.ThrowsAsync<InvalidOperationException>(() => script.RunAsync(skills[0], new AIFunctionArguments(), CancellationToken.None));
+        await Assert.ThrowsAsync<InvalidOperationException>(() => script.RunAsync(skills[0], null, null, CancellationToken.None));
     }
 
     [Fact]
@@ -204,10 +204,10 @@ public sealed class AgentFileSkillsSourceScriptTests : IDisposable
     {
         // Arrange
         CreateSkillWithScript(this._testRoot, "args-skill", "Args test", "Body.", "scripts/test.py", "print('ok')");
-        AIFunctionArguments? capturedArgs = null;
+        JsonElement? capturedArgs = null;
         var source = new AgentFileSkillsSource(
             this._testRoot,
-            (skill, script, args, ct) =>
+            (skill, script, args, sp, ct) =>
             {
                 capturedArgs = args;
                 return Task.FromResult<object?>("done");
@@ -215,17 +215,15 @@ public sealed class AgentFileSkillsSourceScriptTests : IDisposable
 
         // Act
         var skills = await source.GetSkillsAsync(CancellationToken.None);
-        var arguments = new AIFunctionArguments
-        {
-            ["value"] = 26.2,
-            ["factor"] = 1.60934
-        };
-        await skills[0].Scripts![0].RunAsync(skills[0], arguments, CancellationToken.None);
+        using var argumentsDoc = JsonDocument.Parse("""{"value":26.2,"factor":1.60934}""");
+        var arguments = argumentsDoc.RootElement;
+        await skills[0].Scripts![0].RunAsync(skills[0], arguments, null, CancellationToken.None);
 
         // Assert
         Assert.NotNull(capturedArgs);
-        Assert.Equal(26.2, capturedArgs["value"]);
-        Assert.Equal(1.60934, capturedArgs["factor"]);
+        Assert.Equal(JsonValueKind.Object, capturedArgs!.Value.ValueKind);
+        Assert.Equal(26.2, capturedArgs.Value.GetProperty("value").GetDouble());
+        Assert.Equal(1.60934, capturedArgs.Value.GetProperty("factor").GetDouble());
     }
 
     [Fact]

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentInlineSkillScriptTests.cs

@@ -5,7 +5,6 @@ using System.Reflection;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
 
 namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
 
@@ -22,7 +21,7 @@ public sealed class AgentInlineSkillScriptTests
         var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
 
         // Act
-        var result = await script.RunAsync(skill, new AIFunctionArguments(), CancellationToken.None);
+        var result = await script.RunAsync(skill, null, null, CancellationToken.None);
 
         // Assert
         Assert.Equal("hello", result?.ToString());
@@ -34,10 +33,11 @@ public sealed class AgentInlineSkillScriptTests
         // Arrange
         var script = new AgentInlineSkillScript("add", (int a, int b) => a + b);
         var skill = new AgentInlineSkill("calc-skill", "Calc.", "Instructions.");
-        var args = new AIFunctionArguments { ["a"] = 3, ["b"] = 7 };
+        using var argsDoc = JsonDocument.Parse("""{"a":3,"b":7}""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.Equal(10, int.Parse(result?.ToString()!));
@@ -129,10 +129,11 @@ public sealed class AgentInlineSkillScriptTests
         }, serializerOptions: jso);
         var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "test", MaxResults = 5 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert — the custom input type was deserialized and the response was produced
         Assert.NotNull(result);
@@ -145,10 +146,11 @@ public sealed class AgentInlineSkillScriptTests
         // Arrange
         var script = new AgentInlineSkillScript("echo", (string message) => message);
         var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
-        var args = new AIFunctionArguments { ["message"] = "hello world" };
+        using var argsDoc = JsonDocument.Parse("""{"message":"hello world"}""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.Equal("hello world", result?.ToString());
@@ -175,10 +177,11 @@ public sealed class AgentInlineSkillScriptTests
         var method = typeof(AgentInlineSkillScriptTests).GetMethod(nameof(StaticScriptHelper), BindingFlags.NonPublic | BindingFlags.Static)!;
         var script = new AgentInlineSkillScript("static-method-script", method, target: null);
         var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
-        var args = new AIFunctionArguments { ["input"] = "hello" };
+        using var argsDoc = JsonDocument.Parse("""{"input":"hello"}""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        var result = await script.RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert
         Assert.Equal("HELLO", result?.ToString());
@@ -191,10 +194,11 @@ public sealed class AgentInlineSkillScriptTests
         var method = typeof(AgentInlineSkillScriptTests).GetMethod(nameof(InstanceScriptHelper), BindingFlags.NonPublic | BindingFlags.Instance)!;
         var script = new AgentInlineSkillScript("instance-method-script", method, target: this);
         var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
-        var args = new AIFunctionArguments { ["input"] = "test" };
+        using var argsDoc2 = JsonDocument.Parse("""{"input":"test"}""");
+        var args2 = argsDoc2.RootElement;
 
         // Act
-        var result = await script.RunAsync(skill, args, CancellationToken.None);
+        var result = await script.RunAsync(skill, args2, null, CancellationToken.None);
 
         // Assert
         Assert.Equal("test-suffix", result?.ToString());
@@ -223,7 +227,63 @@ public sealed class AgentInlineSkillScriptTests
         Assert.Contains("input", schema!.Value.GetRawText());
     }
 
+    [Fact]
+    public async Task RunAsync_WithNonObjectArguments_ThrowsInvalidOperationExceptionAsync()
+    {
+        // Arrange — inline scripts require a JSON object for arguments
+        var script = new AgentInlineSkillScript("noop", () => "ok");
+        var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
+        using var arrayArgsDoc = JsonDocument.Parse("""["a","b"]""");
+        var arrayArgs = arrayArgsDoc.RootElement;
+
+        // Act & Assert — non-object JSON should fail fast rather than silently dropping arguments
+        await Assert.ThrowsAsync<InvalidOperationException>(
+            () => script.RunAsync(skill, arrayArgs, null, CancellationToken.None));
+    }
+
+    [Fact]
+    public async Task RunAsync_WithNullArguments_TreatsAsNoArgumentsAsync()
+    {
+        // Arrange — a parameterless delegate should succeed when given null arguments
+        var script = new AgentInlineSkillScript("noop", () => "ok");
+        var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
+
+        // Act
+        var result = await script.RunAsync(skill, null, null, CancellationToken.None);
+
+        // Assert
+        Assert.Equal("ok", result?.ToString());
+    }
+
+    [Fact]
+    public async Task RunAsync_ServiceProviderIsForwardedAsync()
+    {
+        // Arrange — delegate that resolves a service from the IServiceProvider
+        IServiceProvider? capturedProvider = null;
+        var script = new AgentInlineSkillScript("svc-test", (IServiceProvider sp) =>
+        {
+            capturedProvider = sp;
+            return "done";
+        });
+        var skill = new AgentInlineSkill("test-skill", "Test.", "Instructions.");
+        var mockProvider = new TestServiceProvider();
+
+        // Act
+        await script.RunAsync(skill, null, mockProvider, CancellationToken.None);
+
+        // Assert
+        Assert.Same(mockProvider, capturedProvider);
+    }
+
     private static string StaticScriptHelper(string input) => input.ToUpperInvariant();
 
     private string InstanceScriptHelper(string input) => input + "-suffix";
+
+    /// <summary>
+    /// Minimal <see cref="IServiceProvider"/> for testing service forwarding.
+    /// </summary>
+    private sealed class TestServiceProvider : IServiceProvider
+    {
+        public object? GetService(Type serviceType) => null;
+    }
 }

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentInlineSkillTests.cs

@@ -433,10 +433,11 @@ public sealed class AgentInlineSkillTests
             TotalCount = request.MaxResults,
         });
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "test", MaxResults = 3 }, jso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await skill.Scripts![0].RunAsync(skill, args, CancellationToken.None);
+        var result = await skill.Scripts![0].RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert — the custom input was deserialized via skill-level JSO and response was produced
         Assert.NotNull(result);
@@ -456,10 +457,11 @@ public sealed class AgentInlineSkillTests
             TotalCount = request.MaxResults,
         }, serializerOptions: scriptJso);
         var inputJson = JsonSerializer.SerializeToElement(new LookupRequest { Query = "override", MaxResults = 7 }, scriptJso);
-        var args = new AIFunctionArguments { ["request"] = inputJson };
+        using var argsDoc = JsonDocument.Parse($$"""{ "request": {{inputJson.GetRawText()}} }""");
+        var args = argsDoc.RootElement;
 
         // Act
-        var result = await skill.Scripts![0].RunAsync(skill, args, CancellationToken.None);
+        var result = await skill.Scripts![0].RunAsync(skill, args, null, CancellationToken.None);
 
         // Assert — per-script JSO takes effect and custom types are properly marshaled
         Assert.NotNull(result);

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/AgentSkillsProviderTests.cs

@@ -4,6 +4,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.AI;
@@ -15,7 +16,7 @@ namespace Microsoft.Agents.AI.UnitTests.AgentSkills;
 /// </summary>
 public sealed class AgentSkillsProviderTests : IDisposable
 {
-    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, ct) => Task.FromResult<object?>(null);
+    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, sp, ct) => Task.FromResult<object?>(null);
     private readonly string _testRoot;
     private readonly TestAIAgent _agent = new();
 
@@ -462,7 +463,7 @@ public sealed class AgentSkillsProviderTests : IDisposable
         // Act — call UseFileScriptRunner AFTER UseFileSkill (the bug scenario)
         var provider = new AgentSkillsProviderBuilder()
             .UseFileSkill(this._testRoot)
-            .UseFileScriptRunner((skill, script, args, ct) =>
+            .UseFileScriptRunner((skill, script, args, sp, ct) =>
             {
                 executorCalled = true;
                 return Task.FromResult<object?>("executed");
@@ -487,6 +488,62 @@ public sealed class AgentSkillsProviderTests : IDisposable
         Assert.True(executorCalled);
     }
 
+    [Fact]
+    public async Task RunSkillScript_ForwardsJsonArgumentsAndServiceProviderToRunnerAsync()
+    {
+        // Arrange — create a skill with a script file
+        string skillDir = Path.Combine(this._testRoot, "fwd-skill");
+        Directory.CreateDirectory(Path.Combine(skillDir, "scripts"));
+        File.WriteAllText(
+            Path.Combine(skillDir, "SKILL.md"),
+            "---\nname: fwd-skill\ndescription: Forwarding test\n---\nBody.");
+        File.WriteAllText(
+            Path.Combine(skillDir, "scripts", "run.py"),
+            "print('ok')");
+
+        JsonElement? capturedArgs = null;
+        IServiceProvider? capturedServiceProvider = null;
+
+        var provider = new AgentSkillsProviderBuilder()
+            .UseFileSkill(this._testRoot)
+            .UseFileScriptRunner((skill, script, args, sp, ct) =>
+            {
+                capturedArgs = args;
+                capturedServiceProvider = sp;
+                return Task.FromResult<object?>("executed");
+            })
+            .Build();
+
+        var mockServiceProvider = new TestServiceProvider();
+        var invokingContext = new AIContextProvider.InvokingContext(this._agent, session: null, new AIContext());
+        var result = await provider.InvokingAsync(invokingContext, CancellationToken.None);
+        var runScriptTool = result.Tools!.First(t => t.Name == "run_skill_script") as AIFunction;
+
+        // Act — invoke with JsonElement arguments and a service provider
+        using var argsJsonDoc = JsonDocument.Parse("""["arg1","arg2"]""");
+        var argsJson = argsJsonDoc.RootElement;
+        await runScriptTool!.InvokeAsync(new AIFunctionArguments(new Dictionary<string, object?>
+        {
+            ["skillName"] = "fwd-skill",
+            ["scriptName"] = "scripts/run.py",
+            ["arguments"] = argsJson,
+        })
+        {
+            Services = mockServiceProvider,
+        });
+
+        // Assert — JsonElement arguments and service provider are forwarded to the runner
+        Assert.NotNull(capturedArgs);
+        Assert.Equal(JsonValueKind.Array, capturedArgs!.Value.ValueKind);
+        Assert.Equal("""["arg1","arg2"]""", capturedArgs.Value.GetRawText());
+        Assert.Same(mockServiceProvider, capturedServiceProvider);
+    }
+
+    private sealed class TestServiceProvider : IServiceProvider
+    {
+        public object? GetService(Type serviceType) => null;
+    }
+
     private static void CreateSkillIn(string root, string name, string description, string body)
     {
         string skillDir = Path.Combine(root, name);

dotnet/tests/Microsoft.Agents.AI.UnitTests/AgentSkills/FileAgentSkillLoaderTests.cs

@@ -15,7 +15,7 @@ public sealed class FileAgentSkillLoaderTests : IDisposable
     private static readonly string[] s_customExtensions = [".custom"];
     private static readonly string[] s_validExtensions = [".md", ".json", ".custom"];
     private static readonly string[] s_mixedValidInvalidExtensions = [".md", "json"];
-    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, ct) => Task.FromResult<object?>(null);
+    private static readonly AgentFileSkillScriptRunner s_noOpExecutor = (skill, script, args, sp, ct) => Task.FromResult<object?>(null);
 
     private readonly string _testRoot;
 

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests/Framework/IntegrationTest.cs

@@ -60,10 +60,20 @@ public abstract class IntegrationTest : IDisposable
 
     protected async ValueTask<DeclarativeWorkflowOptions> CreateOptionsAsync(bool externalConversation = false, params IEnumerable<AIFunction> functionTools)
     {
-        return await this.CreateOptionsAsync(externalConversation, mcpToolProvider: null, functionTools).ConfigureAwait(false);
+        return await this.CreateOptionsAsync(externalConversation, mcpToolProvider: null, httpRequestHandler: null, functionTools).ConfigureAwait(false);
     }
 
     protected async ValueTask<DeclarativeWorkflowOptions> CreateOptionsAsync(bool externalConversation, IMcpToolHandler? mcpToolProvider, params IEnumerable<AIFunction> functionTools)
+    {
+        return await this.CreateOptionsAsync(externalConversation, mcpToolProvider, httpRequestHandler: null, functionTools).ConfigureAwait(false);
+    }
+
+    protected async ValueTask<DeclarativeWorkflowOptions> CreateOptionsAsync(bool externalConversation, IHttpRequestHandler? httpRequestHandler, params IEnumerable<AIFunction> functionTools)
+    {
+        return await this.CreateOptionsAsync(externalConversation, mcpToolProvider: null, httpRequestHandler, functionTools).ConfigureAwait(false);
+    }
+
+    protected async ValueTask<DeclarativeWorkflowOptions> CreateOptionsAsync(bool externalConversation, IMcpToolHandler? mcpToolProvider, IHttpRequestHandler? httpRequestHandler, params IEnumerable<AIFunction> functionTools)
     {
         AzureAgentProvider agentProvider =
             new(this.TestEndpoint, TestAzureCliCredentials.CreateAzureCliCredential())
@@ -82,7 +92,8 @@ public abstract class IntegrationTest : IDisposable
             {
                 ConversationId = conversationId,
                 LoggerFactory = this.Output,
-                McpToolHandler = mcpToolProvider
+                McpToolHandler = mcpToolProvider,
+                HttpRequestHandler = httpRequestHandler,
             };
     }
 

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests/InvokeToolWorkflowTest.cs

@@ -45,6 +45,15 @@ public sealed class InvokeToolWorkflowTest(ITestOutputHelper output) : Integrati
 
     #endregion
 
+    #region InvokeHttpRequest Tests
+
+    [RetryTheory(3, 5000)]
+    [InlineData("HttpRequest.yaml", "visibility: public")]
+    public Task ValidateHttpRequestAsync(string workflowFileName, string? expectedResultContains) =>
+        this.RunHttpRequestTestAsync(workflowFileName, expectedResultContains);
+
+    #endregion
+
     #region InvokeFunctionTool Test Helpers
 
     /// <summary>
@@ -250,6 +259,40 @@ public sealed class InvokeToolWorkflowTest(ITestOutputHelper output) : Integrati
 
     #endregion
 
+    #region InvokeHttpRequest Test Helpers
+
+    /// <summary>
+    /// Runs an HttpRequestAction workflow test with the specified configuration.
+    /// </summary>
+    private async Task RunHttpRequestTestAsync(
+        string workflowFileName,
+        string? expectedResultContains = null)
+    {
+        // Arrange
+        string workflowPath = GetWorkflowPath(workflowFileName);
+        await using DefaultHttpRequestHandler httpRequestHandler = new();
+        DeclarativeWorkflowOptions workflowOptions = await this.CreateOptionsAsync(
+            externalConversation: false,
+            httpRequestHandler: httpRequestHandler);
+
+        Workflow workflow = DeclarativeWorkflowBuilder.Build<string>(workflowPath, workflowOptions);
+        WorkflowHarness harness = new(workflow, runId: Path.GetFileNameWithoutExtension(workflowPath));
+
+        // Act
+        WorkflowEvents workflowEvents = await harness.RunWorkflowAsync("start").ConfigureAwait(false);
+
+        // Assert - Verify executor and action events
+        AssertWorkflowEventsEmitted(workflowEvents);
+
+        // Assert - Verify expected result if specified
+        if (expectedResultContains is not null)
+        {
+            AssertResultContains(workflowEvents, expectedResultContains);
+        }
+    }
+
+    #endregion
+
     #region Shared Helpers
 
     private static void AssertWorkflowEventsEmitted(WorkflowEvents workflowEvents)

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests/Workflows/HttpRequest.yaml

@@ -0,0 +1,32 @@
+#
+# This workflow tests invoking HttpRequestAction end-to-end.
+# Uses the public GitHub API (unauthenticated) to fetch repo metadata.
+#
+kind: Workflow
+trigger:
+
+  kind: OnConversationStart
+  id: workflow_http_request_test
+  actions:
+
+    # Set the repo owner used to form the request URL.
+    - kind: SetVariable
+      id: set_repo_owner
+      variable: Local.RepoOwner
+      value: dotnet
+
+    # Invoke the GitHub repo API.
+    - kind: HttpRequestAction
+      id: fetch_repo_info
+      conversationId: =System.ConversationId
+      method: GET
+      url: =Concatenate("https://api.github.com/repos/", Local.RepoOwner, "/runtime")
+      headers:
+        Accept: application/vnd.github+json
+        User-Agent: agent-framework-integration-test
+      response: Local.RepoInfo
+
+    # Surface the Repo visibility field from the parsed JSON response.
+    - kind: SendMessage
+      id: show_visibility
+      message: "visibility: {Local.RepoInfo.visibility}"

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/DeclarativeWorkflowTest.cs

@@ -181,6 +181,7 @@ public sealed class DeclarativeWorkflowTest(ITestOutputHelper output) : Workflow
     [InlineData("ResetVariable.yaml", 2, "clear_var")]
     [InlineData("MixedScopes.yaml", 2, "activity_input")]
     [InlineData("CaseInsensitive.yaml", 6, "end_when_match")]
+    [InlineData("HttpRequest.yaml", 1, "http_request")]
     public async Task ExecuteActionAsync(string workflowFile, int expectedCount, string expectedId)
     {
         await this.RunWorkflowAsync(workflowFile);
@@ -200,7 +201,6 @@ public sealed class DeclarativeWorkflowTest(ITestOutputHelper output) : Workflow
     [InlineData(typeof(EmitEvent.Builder))]
     [InlineData(typeof(GetActivityMembers.Builder))]
     [InlineData(typeof(GetConversationMembers.Builder))]
-    [InlineData(typeof(HttpRequestAction.Builder))]
     [InlineData(typeof(InvokeAIBuilderModelAction.Builder))]
     [InlineData(typeof(InvokeConnectorAction.Builder))]
     [InlineData(typeof(InvokeCustomModelAction.Builder))]
@@ -266,6 +266,7 @@ public sealed class DeclarativeWorkflowTest(ITestOutputHelper output) : Workflow
     [InlineData("SendActivity.yaml", "activity_input")]
     [InlineData("SetVariable.yaml", "set_var")]
     [InlineData("SetTextVariable.yaml", "set_text")]
+    [InlineData("HttpRequest.yaml", "http_request")]
     public async Task CancelRunAsync(string workflowPath, string expectedExecutedId)
     {
         // Arrange
@@ -374,7 +375,12 @@ public sealed class DeclarativeWorkflowTest(ITestOutputHelper output) : Workflow
     {
         using StreamReader yamlReader = File.OpenText(Path.Combine("Workflows", workflowPath));
         Mock<ResponseAgentProvider> mockAgentProvider = CreateMockProvider($"{workflowInput}");
-        DeclarativeWorkflowOptions workflowContext = new(mockAgentProvider.Object) { LoggerFactory = this.Output };
+        DeclarativeWorkflowOptions workflowContext =
+            new(mockAgentProvider.Object)
+            {
+                LoggerFactory = this.Output,
+                HttpRequestHandler = CreateMockHttpRequestHandler().Object,
+            };
         return DeclarativeWorkflowBuilder.Build<TInput>(yamlReader, workflowContext);
     }
 
@@ -385,4 +391,18 @@ public sealed class DeclarativeWorkflowTest(ITestOutputHelper output) : Workflow
         mockAgentProvider.Setup(provider => provider.CreateMessageAsync(It.IsAny<string>(), It.IsAny<ChatMessage>(), It.IsAny<CancellationToken>())).Returns(Task.FromResult(new ChatMessage(ChatRole.Assistant, input)));
         return mockAgentProvider;
     }
+
+    private static Mock<IHttpRequestHandler> CreateMockHttpRequestHandler()
+    {
+        Mock<IHttpRequestHandler> mockHandler = new(MockBehavior.Loose);
+        mockHandler
+            .Setup(handler => handler.SendAsync(It.IsAny<HttpRequestInfo>(), It.IsAny<CancellationToken>()))
+            .Returns(() => Task.FromResult(new HttpRequestResult
+            {
+                StatusCode = 200,
+                IsSuccessStatusCode = true,
+                Body = "{\"ok\":true}",
+            }));
+        return mockHandler;
+    }
 }

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/DefaultHttpRequestHandlerTests.cs

@@ -0,0 +1,510 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Net;
+using System.Net.Http;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using FluentAssertions;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative.UnitTests;
+
+/// <summary>
+/// Unit tests for <see cref="DefaultHttpRequestHandler"/>.
+/// </summary>
+public sealed class DefaultHttpRequestHandlerTests
+{
+    private static readonly string[] s_setCookieValues = ["a=1", "b=2"];
+
+    private const string TestUrl = "https://api.example.test/resource";
+
+    #region Constructor Tests
+
+    [Fact]
+    public async Task ConstructorWithNoParametersCreatesInstanceAsync()
+    {
+        // Act
+        await using DefaultHttpRequestHandler handler = new();
+
+        // Assert
+        handler.Should().NotBeNull();
+    }
+
+    [Fact]
+    public async Task ConstructorWithNullProviderCreatesInstanceAsync()
+    {
+        // Act
+        await using DefaultHttpRequestHandler handler = new(httpClientProvider: null);
+
+        // Assert
+        handler.Should().NotBeNull();
+    }
+
+    [Fact]
+    public void ConstructorWithNullHttpClientThrows()
+    {
+        // Act
+        Action act = () => _ = new DefaultHttpRequestHandler((HttpClient)null!);
+
+        // Assert
+        act.Should().Throw<ArgumentNullException>();
+    }
+
+    [Fact]
+    public async Task ConstructorWithHttpClientUsesSuppliedClientForAllRequestsAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent("ok", Encoding.UTF8, "text/plain"),
+            }));
+        using HttpClient suppliedClient = new(messageHandler);
+        await using DefaultHttpRequestHandler handler = new(suppliedClient);
+        HttpRequestInfo request = new() { Method = "GET", Url = TestUrl };
+
+        // Act
+        HttpRequestResult result = await handler.SendAsync(request);
+
+        // Assert - the supplied HttpClient's underlying handler saw the request
+        messageHandler.LastRequest.Should().NotBeNull();
+        messageHandler.LastRequest!.RequestUri!.ToString().Should().Be(TestUrl);
+        result.Body.Should().Be("ok");
+    }
+
+    [Fact]
+    public async Task DisposeAsyncDoesNotDisposeCallerSuppliedHttpClientAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+        using HttpClient suppliedClient = new(messageHandler);
+
+        // Act
+        DefaultHttpRequestHandler handler = new(suppliedClient);
+        await handler.DisposeAsync();
+
+        // Assert - supplied client remains usable (not disposed)
+        Func<Task> act = async () => await suppliedClient.GetAsync(new Uri(TestUrl));
+        await act.Should().NotThrowAsync<ObjectDisposedException>();
+    }
+
+    #endregion
+
+    #region Argument Validation Tests
+
+    [Fact]
+    public async Task SendAsyncWithNullRequestThrowsAsync()
+    {
+        // Arrange
+        await using DefaultHttpRequestHandler handler = new();
+
+        // Act
+        Func<Task> act = async () => await handler.SendAsync(null!);
+
+        // Assert
+        await act.Should().ThrowAsync<ArgumentNullException>();
+    }
+
+    [Fact]
+    public async Task SendAsyncWithEmptyUrlThrowsAsync()
+    {
+        // Arrange
+        await using DefaultHttpRequestHandler handler = new();
+        HttpRequestInfo request = new() { Method = "GET", Url = "" };
+
+        // Act
+        Func<Task> act = async () => await handler.SendAsync(request);
+
+        // Assert
+        await act.Should().ThrowAsync<ArgumentException>();
+    }
+
+    [Fact]
+    public async Task SendAsyncWithEmptyMethodThrowsAsync()
+    {
+        // Arrange
+        await using DefaultHttpRequestHandler handler = new();
+        HttpRequestInfo request = new() { Method = "", Url = TestUrl };
+
+        // Act
+        Func<Task> act = async () => await handler.SendAsync(request);
+
+        // Assert
+        await act.Should().ThrowAsync<ArgumentException>();
+    }
+
+    #endregion
+
+    #region Send Behavior Tests
+
+    [Fact]
+    public async Task SendAsyncUsesProvidedHttpClientAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent("hello", Encoding.UTF8, "text/plain"),
+            }));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new() { Method = "GET", Url = TestUrl };
+
+        // Act
+        HttpRequestResult result = await handler.SendAsync(request);
+
+        // Assert
+        messageHandler.LastRequest.Should().NotBeNull();
+        messageHandler.LastRequest!.Method.Should().Be(HttpMethod.Get);
+        messageHandler.LastRequest.RequestUri!.ToString().Should().Be(TestUrl);
+        result.StatusCode.Should().Be(200);
+        result.IsSuccessStatusCode.Should().BeTrue();
+        result.Body.Should().Be("hello");
+    }
+
+    [Fact]
+    public async Task SendAsyncMapsAllKnownMethodsAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        foreach (string method in new[] { "GET", "POST", "PUT", "PATCH", "DELETE", "CUSTOM" })
+        {
+            HttpRequestInfo request = new() { Method = method, Url = TestUrl };
+
+            // Act
+            await handler.SendAsync(request);
+
+            // Assert
+            messageHandler.LastRequest!.Method.Method.Should().Be(method);
+        }
+    }
+
+    [Fact]
+    public async Task SendAsyncNormalizesWhitespaceAroundCustomMethodAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+        HttpRequestInfo request = new() { Method = "  custom  ", Url = TestUrl };
+
+        // Act
+        await handler.SendAsync(request);
+
+        // Assert - fallback path should apply the same Trim/ToUpperInvariant normalization.
+        messageHandler.LastRequest!.Method.Method.Should().Be("CUSTOM");
+    }
+
+    [Fact]
+    public async Task SendAsyncAppliesBodyAndContentTypeAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new()
+        {
+            Method = "POST",
+            Url = TestUrl,
+            Body = "{\"hello\":\"world\"}",
+            BodyContentType = "application/json",
+        };
+
+        // Act
+        await handler.SendAsync(request);
+
+        // Assert
+        messageHandler.LastRequestBody.Should().Be("{\"hello\":\"world\"}");
+        messageHandler.LastRequestContentType.Should().Be("application/json");
+    }
+
+    [Fact]
+    public async Task SendAsyncAppliesRequestHeadersAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new()
+        {
+            Method = "GET",
+            Url = TestUrl,
+            Headers = new Dictionary<string, string>
+            {
+                ["Authorization"] = "Bearer secret",
+                ["Accept"] = "application/json",
+            },
+        };
+
+        // Act
+        await handler.SendAsync(request);
+
+        // Assert
+        messageHandler.LastRequest!.Headers.Authorization!.ToString().Should().Be("Bearer secret");
+        messageHandler.LastRequest.Headers.Accept.Should().Contain(mediaType => mediaType.MediaType == "application/json");
+    }
+
+    [Fact]
+    public async Task SendAsyncRoutesContentHeadersToBodyAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new()
+        {
+            Method = "POST",
+            Url = TestUrl,
+            Body = "raw",
+            BodyContentType = "text/plain",
+            Headers = new Dictionary<string, string>
+            {
+                ["Content-Language"] = "en-US",
+            },
+        };
+
+        // Act
+        await handler.SendAsync(request);
+
+        // Assert
+        messageHandler.LastRequest!.Content!.Headers.ContentLanguage.Should().Contain("en-US");
+    }
+
+    [Fact]
+    public async Task SendAsyncCapturesResponseHeadersAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+        {
+#pragma warning disable CA2025
+            HttpResponseMessage response = new(HttpStatusCode.OK)
+            {
+                Content = new StringContent("ok", Encoding.UTF8, "text/plain"),
+            };
+            response.Headers.Add("X-Request-Id", "request-1");
+            response.Headers.Add("Set-Cookie", s_setCookieValues);
+            return Task.FromResult(response);
+#pragma warning restore CA2025
+        });
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new() { Method = "GET", Url = TestUrl };
+
+        // Act
+        HttpRequestResult result = await handler.SendAsync(request);
+
+        // Assert
+        result.Headers.Should().NotBeNull();
+        result.Headers!.Should().ContainKey("X-Request-Id");
+        result.Headers!["Set-Cookie"].Should().BeEquivalentTo(s_setCookieValues);
+        // Content headers also flattened in.
+        result.Headers!.Should().ContainKey("Content-Type");
+    }
+
+    [Fact]
+    public async Task SendAsyncReturnsFailureStatusWithoutThrowingAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new((req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.BadRequest)
+            {
+                Content = new StringContent("bad request", Encoding.UTF8, "text/plain"),
+            }));
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new() { Method = "GET", Url = TestUrl };
+
+        // Act
+        HttpRequestResult result = await handler.SendAsync(request);
+
+        // Assert
+        result.IsSuccessStatusCode.Should().BeFalse();
+        result.StatusCode.Should().Be(400);
+        result.Body.Should().Be("bad request");
+    }
+
+    [Fact]
+    public async Task SendAsyncTimeoutCancelsRequestAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler messageHandler = new(async (req, ct) =>
+        {
+            await Task.Delay(TimeSpan.FromSeconds(5), ct).ConfigureAwait(false);
+            return new HttpResponseMessage(HttpStatusCode.OK);
+        });
+
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(messageHandler)));
+
+        HttpRequestInfo request = new()
+        {
+            Method = "GET",
+            Url = TestUrl,
+            Timeout = TimeSpan.FromMilliseconds(50),
+        };
+
+        // Act
+        Func<Task> act = async () => await handler.SendAsync(request);
+
+        // Assert
+        await act.Should().ThrowAsync<OperationCanceledException>();
+    }
+
+    [Fact]
+    public async Task SendAsyncFallsBackToOwnedClientWhenProviderReturnsNullAsync()
+    {
+        // Arrange
+        int providerCallCount = 0;
+        await using DefaultHttpRequestHandler handler = new((_, _) =>
+        {
+            providerCallCount++;
+            return Task.FromResult<HttpClient?>(null);
+        });
+
+        HttpRequestInfo request = new() { Method = "GET", Url = "http://127.0.0.1:1/" };
+
+        // Act - owned client will attempt real network and fail, but provider path should have been consulted first.
+        Func<Task> act = async () => await handler.SendAsync(request);
+
+        // Assert
+        await act.Should().ThrowAsync<Exception>();
+        providerCallCount.Should().Be(1);
+    }
+
+    #endregion
+
+    #region DisposeAsync
+
+    [Fact]
+    public async Task DisposeAsyncCompletesAsync()
+    {
+        // Arrange
+        DefaultHttpRequestHandler handler = new();
+
+        // Act
+        Func<Task> act = async () => await handler.DisposeAsync();
+
+        // Assert
+        await act.Should().NotThrowAsync();
+    }
+
+    [Fact]
+    public async Task DisposeAsyncCalledMultipleTimesSucceedsAsync()
+    {
+        // Arrange
+        DefaultHttpRequestHandler handler = new();
+
+        // Act
+        await handler.DisposeAsync();
+        Func<Task> second = async () => await handler.DisposeAsync();
+
+        // Assert
+        await second.Should().NotThrowAsync();
+    }
+
+    #endregion
+
+    #region Query Parameters and Connection Tests
+
+    [Fact]
+    public async Task QueryParametersAreAppendedToUrlAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler fake = new(static (req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(string.Empty) }));
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(fake)));
+
+        HttpRequestInfo info = new()
+        {
+            Method = "GET",
+            Url = TestUrl,
+            QueryParameters = new Dictionary<string, string>
+            {
+                ["filter"] = "active items",
+                ["ids"] = "1,2,3",
+            },
+        };
+
+        // Act
+        await handler.SendAsync(info);
+
+        // Assert
+        fake.LastRequest.Should().NotBeNull();
+        string? query = fake.LastRequest!.RequestUri!.Query;
+        query.Should().Contain("filter=active%20items");
+        query.Should().Contain("ids=1%2C2%2C3");
+    }
+
+    [Fact]
+    public async Task QueryParametersPreserveExistingQueryStringAsync()
+    {
+        // Arrange
+        TestHttpMessageHandler fake = new(static (req, _) =>
+            Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(string.Empty) }));
+        await using DefaultHttpRequestHandler handler = new((_, _) => Task.FromResult<HttpClient?>(new HttpClient(fake)));
+
+        HttpRequestInfo info = new()
+        {
+            Method = "GET",
+            Url = TestUrl + "?existing=yes",
+            QueryParameters = new Dictionary<string, string>
+            {
+                ["added"] = "true",
+            },
+        };
+
+        // Act
+        await handler.SendAsync(info);
+
+        // Assert
+        fake.LastRequest!.RequestUri!.Query.Should().Be("?existing=yes&added=true");
+    }
+
+    #endregion
+
+    private sealed class TestHttpMessageHandler : HttpMessageHandler
+    {
+        private readonly Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> _responseFactory;
+
+        public TestHttpMessageHandler(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> responseFactory)
+        {
+            this._responseFactory = responseFactory;
+        }
+
+        public HttpRequestMessage? LastRequest { get; private set; }
+
+        public string? LastRequestBody { get; private set; }
+
+        public string? LastRequestContentType { get; private set; }
+
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            this.LastRequest = request;
+            if (request.Content is not null)
+            {
+#if NET
+                this.LastRequestBody = await request.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false);
+#else
+                this.LastRequestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+#endif
+                this.LastRequestContentType = request.Content.Headers.ContentType?.MediaType;
+            }
+            return await this._responseFactory(request, cancellationToken).ConfigureAwait(false);
+        }
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/Extensions/ChatMessageExtensionsTests.cs

@@ -769,4 +769,165 @@ public sealed class ChatMessageExtensionsTests
                 break;
         }
     }
+
+    [Fact]
+    public void MergeForLastMessageReturnsInputWhenInputMessageIsNull()
+    {
+        // Arrange
+        ChatMessage input = new(ChatRole.User, "hello") { MessageId = "local" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(null);
+
+        // Assert
+        Assert.Same(input, result);
+    }
+
+    [Fact]
+    public void MergeForLastMessageReturnsSameInstanceAsRoundTripped()
+    {
+        // Arrange: returning the round-tripped instance keeps the merge forward-compatible
+        // with future ChatMessage properties (e.g., new metadata fields) without explicit copies.
+        ChatMessage input = new(ChatRole.User, "original");
+        ChatMessage roundTripped = new(ChatRole.User, "stripped") { MessageId = "server" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert
+        Assert.Same(roundTripped, result);
+    }
+
+    [Fact]
+    public void MergeForLastMessagePrefersOriginalTextOverRoundTrippedText()
+    {
+        // Arrange
+        ChatMessage input = new(ChatRole.User, "original text");
+        ChatMessage roundTripped = new(ChatRole.User, "stripped") { MessageId = "server-id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert
+        Assert.Equal("server-id", result.MessageId);
+        Assert.Equal("original text", result.Text);
+        TextContent text = Assert.IsType<TextContent>(Assert.Single(result.Contents));
+        Assert.Equal("original text", text.Text);
+    }
+
+    [Fact]
+    public void MergeForLastMessageReplacesTextInPlaceAndKeepsServerMedia()
+    {
+        // Arrange
+        HostedFileContent serverRef = new("file-abc");
+        ChatMessage input = new(ChatRole.User, [new TextContent("look at this:"), new DataContent("data:image/jpeg;base64,QUJD", "image/jpeg")]);
+        ChatMessage roundTripped = new(ChatRole.User, [new TextContent("stripped"), serverRef]) { MessageId = "server-id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert: server's text slot is replaced with original text; server's media reference is preserved.
+        Assert.Equal("server-id", result.MessageId);
+        Assert.Collection(result.Contents,
+            c => Assert.Equal("look at this:", Assert.IsType<TextContent>(c).Text),
+            c => Assert.Same(serverRef, c));
+    }
+
+    [Fact]
+    public void MergeForLastMessageAppendsOriginalTextWhenRoundTripHasNoTextSlot()
+    {
+        // Arrange: round-tripped message has only media (no text slot to replace).
+        HostedFileContent serverRef = new("file-1");
+        ChatMessage input = new(ChatRole.User, [new TextContent("middle"), new DataContent("data:image/jpeg;base64,QUE=", "image/jpeg")]);
+        ChatMessage roundTripped = new(ChatRole.User, [serverRef]) { MessageId = "id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert: media kept; original text appended at end.
+        Assert.Collection(result.Contents,
+            c => Assert.Same(serverRef, c),
+            c => Assert.Equal("middle", Assert.IsType<TextContent>(c).Text));
+    }
+
+    [Fact]
+    public void MergeForLastMessageReplacesMultipleTextSlotsInOrder()
+    {
+        // Arrange: input has two text items; round-tripped has two text slots interleaved with media.
+        HostedFileContent firstRef = new("file-1");
+        HostedFileContent secondRef = new("file-2");
+        ChatMessage input = new(ChatRole.User, [new TextContent("first"), new TextContent("second")]);
+        ChatMessage roundTripped = new(ChatRole.User, [firstRef, new TextContent("a"), secondRef, new TextContent("b")]) { MessageId = "id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert
+        Assert.Collection(result.Contents,
+            c => Assert.Same(firstRef, c),
+            c => Assert.Equal("first", Assert.IsType<TextContent>(c).Text),
+            c => Assert.Same(secondRef, c),
+            c => Assert.Equal("second", Assert.IsType<TextContent>(c).Text));
+    }
+
+    [Fact]
+    public void MergeForLastMessageFallsBackToInputTextWhenInputHasNoTextContent()
+    {
+        // Arrange: ChatMessage(role, "string") populates Text but no explicit TextContent
+        // when Contents is initially empty in some construction paths. Verify we still
+        // recover the original Text via input.Text.
+        ChatMessage input = new(ChatRole.User, "fallback text");
+        ChatMessage roundTripped = new(ChatRole.User, [new TextContent("stripped")]) { MessageId = "id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert
+        Assert.Equal("fallback text", Assert.IsType<TextContent>(Assert.Single(result.Contents)).Text);
+    }
+
+    [Fact]
+    public void MergeForLastMessagePreservesServerAuthoredProperties()
+    {
+        // Arrange: server (round-trip) is authoritative for metadata. Returning the
+        // round-tripped instance means any future ChatMessage property is automatically
+        // preserved without code changes here.
+        ChatMessage input = new(ChatRole.User, "hi")
+        {
+            AuthorName = "client-side",
+            AdditionalProperties = new AdditionalPropertiesDictionary { ["client"] = "value" },
+        };
+        ChatMessage roundTripped = new(ChatRole.User, [new TextContent("stripped")])
+        {
+            MessageId = "server",
+            AuthorName = "server-side",
+            AdditionalProperties = new AdditionalPropertiesDictionary { ["server"] = "value" },
+        };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert
+        Assert.Equal("server", result.MessageId);
+        Assert.Equal("server-side", result.AuthorName);
+        Assert.NotNull(result.AdditionalProperties);
+        Assert.True(result.AdditionalProperties.ContainsKey("server"));
+        Assert.False(result.AdditionalProperties.ContainsKey("client"));
+    }
+
+    [Fact]
+    public void MergeForLastMessageHandlesEmptyInputContents()
+    {
+        // Arrange
+        ChatMessage input = new(ChatRole.User, new List<AIContent>());
+        HostedFileContent serverRef = new("file-only");
+        ChatMessage roundTripped = new(ChatRole.User, [serverRef]) { MessageId = "id" };
+
+        // Act
+        ChatMessage result = input.MergeForLastMessage(roundTripped);
+
+        // Assert: nothing to splice; round-tripped returned unchanged.
+        Assert.Same(roundTripped, result);
+        Assert.Equal("file-only", Assert.IsType<HostedFileContent>(Assert.Single(result.Contents)).FileId);
+    }
 }

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/ObjectModel/HttpRequestExecutorTest.cs

@@ -0,0 +1,759 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Agents.AI.Workflows.Declarative.ObjectModel;
+using Microsoft.Agents.AI.Workflows.Declarative.PowerFx;
+using Microsoft.Agents.ObjectModel;
+using Microsoft.Extensions.AI;
+using Microsoft.PowerFx.Types;
+using Moq;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative.UnitTests.ObjectModel;
+
+/// <summary>
+/// Tests for <see cref="HttpRequestExecutor"/>.
+/// </summary>
+public sealed class HttpRequestExecutorTest(ITestOutputHelper output) : WorkflowActionExecutorTest(output)
+{
+    private const string TestUrl = "https://api.example.com/data";
+
+    private readonly Mock<ResponseAgentProvider> _agentProvider = new(MockBehavior.Loose);
+
+    [Fact]
+    public void InvalidModel()
+    {
+        // Arrange
+        Mock<IHttpRequestHandler> mockHandler = new();
+
+        // Act & Assert
+        Assert.Throws<DeclarativeModelException>(() => new HttpRequestExecutor(
+            new HttpRequestAction(),
+            mockHandler.Object,
+            this._agentProvider.Object,
+            this.State));
+    }
+
+    [Fact]
+    public void HttpRequestIsDiscreteAction()
+    {
+        // Arrange
+        Mock<IHttpRequestHandler> mockHandler = new();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestIsDiscreteAction),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+        HttpRequestExecutor action = new(model, mockHandler.Object, this._agentProvider.Object, this.State);
+
+        // Act & Assert — IsDiscreteAction should be true for HttpRequest (single-step action).
+        VerifyIsDiscrete(action, isDiscrete: true);
+    }
+
+    [Fact]
+    public async Task HttpGetReturnsJsonObjectAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string ResponseVar = "Result";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetReturnsJsonObjectAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            responseVariable: ResponseVar);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{\"key\":\"value\",\"number\":42}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        Assert.IsType<RecordValue>(this.State.Get(ResponseVar), exactMatch: false);
+        handler.VerifySent(info => info.Method == "GET" && info.Url == TestUrl);
+    }
+
+    [Fact]
+    public async Task HttpGetReturnsPlainStringAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string ResponseVar = "Result";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetReturnsPlainStringAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            responseVariable: ResponseVar);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("not-json content"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this.VerifyState(ResponseVar, FormulaValue.New("not-json content"));
+    }
+
+    [Fact]
+    public async Task HttpGetWithEmptyBodyYieldsBlankAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string ResponseVar = "Result";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetWithEmptyBodyYieldsBlankAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            responseVariable: ResponseVar);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult(null));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this.VerifyUndefined(ResponseVar);
+    }
+
+    [Fact]
+    public async Task HttpGetForwardsHeadersAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetForwardsHeadersAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            headers: new Dictionary<string, string>
+            {
+                ["Authorization"] = "Bearer token",
+                ["Accept"] = "application/json",
+            });
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.Headers?["Authorization"] == "Bearer token" &&
+            info.Headers?["Accept"] == "application/json");
+    }
+
+    [Fact]
+    public async Task HttpPostWithJsonBodyAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpPostWithJsonBodyAsync),
+            url: TestUrl,
+            method: HttpMethodType.Post,
+            jsonBody: new StringDataValue("hello"));
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.Method == "POST" &&
+            info.BodyContentType == "application/json" &&
+            info.Body == "\"hello\"");
+    }
+
+    [Fact]
+    public async Task HttpPostWithRawBodyAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpPostWithRawBodyAsync),
+            url: TestUrl,
+            method: HttpMethodType.Post,
+            rawBody: "raw body content",
+            rawContentType: "text/plain");
+
+        MockHttpRequestHandler handler = new(HttpRequestResult(""));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.BodyContentType == "text/plain" &&
+            info.Body == "raw body content");
+    }
+
+    [Fact]
+    public async Task HttpRequestRaisesOnErrorByDefaultAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestRaisesOnErrorByDefaultAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("server error", statusCode: 500, isSuccess: false));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act & Assert
+        await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+    }
+
+    [Fact]
+    public async Task HttpRequestFailureExceptionTruncatesLongBodyAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestFailureExceptionTruncatesLongBodyAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        string longBody = new('x', 10_000);
+        MockHttpRequestHandler handler = new(HttpRequestResult(longBody, statusCode: 500, isSuccess: false));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        DeclarativeActionException exception =
+            await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+
+        // Assert - message contains status and truncation marker, bounded in length, never the full body.
+        Assert.Contains("500", exception.Message);
+        Assert.Contains("[truncated]", exception.Message);
+        Assert.DoesNotContain(longBody, exception.Message);
+        Assert.True(exception.Message.Length < 512, $"Exception message too long: {exception.Message.Length} chars.");
+    }
+
+    [Fact]
+    public async Task HttpRequestFailureExceptionOmitsEmptyBodyAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestFailureExceptionOmitsEmptyBodyAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult(body: null, statusCode: 404, isSuccess: false));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        DeclarativeActionException exception =
+            await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+
+        // Assert - status present, no stray "Body: ''" noise.
+        Assert.Contains("404", exception.Message);
+        Assert.DoesNotContain("Body:", exception.Message);
+    }
+
+    [Fact]
+    public async Task HttpRequestFailureExceptionSanitizesControlCharsAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestFailureExceptionSanitizesControlCharsAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("line1\r\nline2\tend", statusCode: 400, isSuccess: false));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        DeclarativeActionException exception =
+            await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+
+        // Assert - CR/LF/TAB collapsed to spaces so the message stays on one line.
+        Assert.DoesNotContain("\r", exception.Message);
+        Assert.DoesNotContain("\n", exception.Message);
+        Assert.DoesNotContain("\t", exception.Message);
+        Assert.Contains("line1", exception.Message);
+        Assert.Contains("line2", exception.Message);
+    }
+
+    [Fact]
+    public async Task HttpRequestPassesTimeoutToHandlerAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestPassesTimeoutToHandlerAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            timeoutMilliseconds: 1500);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.Timeout is not null &&
+            info.Timeout.Value == TimeSpan.FromMilliseconds(1500));
+    }
+
+    [Fact]
+    public async Task HttpRequestTimeoutRaisesDeclarativeExceptionAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestTimeoutRaisesDeclarativeExceptionAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(
+            HttpRequestResult("{}"),
+            throwOnSend: new OperationCanceledException());
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act & Assert
+        await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+    }
+
+    [Fact]
+    public async Task HttpRequestTransportFailureRaisesDeclarativeExceptionAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestTransportFailureRaisesDeclarativeExceptionAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(
+            HttpRequestResult("{}"),
+            throwOnSend: new InvalidOperationException("transport failure"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act & Assert
+        await Assert.ThrowsAsync<DeclarativeActionException>(() => this.ExecuteAsync(action));
+    }
+
+    [Fact]
+    public async Task HttpRequestStoresResponseHeadersAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string HeaderVar = "Headers";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestStoresResponseHeadersAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            responseHeadersVariable: HeaderVar);
+
+        Dictionary<string, IReadOnlyList<string>> responseHeaders = new(StringComparer.OrdinalIgnoreCase)
+        {
+            ["X-Request-Id"] = ["abc-123"],
+            ["Set-Cookie"] = ["a=1", "b=2"],
+        };
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}", headers: responseHeaders));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        FormulaValue storedHeaders = this.State.Get(HeaderVar);
+        Assert.IsType<RecordValue>(storedHeaders, exactMatch: false);
+    }
+
+    [Fact]
+    public async Task HttpRequestForwardsQueryParametersAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestForwardsQueryParametersAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            queryParameters: new Dictionary<string, DataValue>
+            {
+                ["filter"] = StringDataValue.Create("active"),
+                ["limit"] = NumberDataValue.Create(10),
+                ["includeDeleted"] = BooleanDataValue.Create(false),
+            });
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.QueryParameters?.Count == 3 &&
+            info.QueryParameters["filter"] == "active" &&
+            info.QueryParameters["limit"] == "10" &&
+            info.QueryParameters["includeDeleted"] == "false");
+    }
+
+    [Fact]
+    public async Task HttpRequestAddsResponseToConversationAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string ConversationId = "conv-12345";
+        const string ResponseBody = "response-text";
+
+        this._agentProvider
+            .Setup(p => p.CreateMessageAsync(It.IsAny<string>(), It.IsAny<ChatMessage>(), It.IsAny<CancellationToken>()))
+            .Returns<string, ChatMessage, CancellationToken>((_, message, _) => Task.FromResult(message));
+
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestAddsResponseToConversationAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            conversationId: ConversationId);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult(ResponseBody));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this._agentProvider.Verify(
+            p => p.CreateMessageAsync(
+                ConversationId,
+                It.Is<ChatMessage>(m => m.Role == ChatRole.Assistant && m.Text == ResponseBody),
+                It.IsAny<CancellationToken>()),
+            Times.Once);
+    }
+
+    [Fact]
+    public async Task HttpRequestWithoutConversationIdSkipsConversationAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestWithoutConversationIdSkipsConversationAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("response"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this._agentProvider.Verify(
+            p => p.CreateMessageAsync(It.IsAny<string>(), It.IsAny<ChatMessage>(), It.IsAny<CancellationToken>()),
+            Times.Never);
+    }
+
+    [Fact]
+    public async Task HttpRequestForwardsConnectionNameAsync()
+    {
+        // Arrange
+        this.State.InitializeSystem();
+        const string ConnectionName = "my-connection";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestForwardsConnectionNameAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            connectionName: ConnectionName);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info => info.ConnectionName == ConnectionName);
+    }
+
+    [Fact]
+    public async Task HttpRequestEmptyConversationIdSkipsConversationAsync()
+    {
+        // Arrange - empty-string conversationId should be treated as unset.
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestEmptyConversationIdSkipsConversationAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            conversationId: "");
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("response"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this._agentProvider.Verify(
+            p => p.CreateMessageAsync(It.IsAny<string>(), It.IsAny<ChatMessage>(), It.IsAny<CancellationToken>()),
+            Times.Never);
+    }
+
+    [Fact]
+    public async Task HttpRequestEmptyResponseBodySkipsConversationAsync()
+    {
+        // Arrange - conversationId set, but empty body should not produce a conversation message.
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestEmptyResponseBodySkipsConversationAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            conversationId: "conv-1");
+
+        MockHttpRequestHandler handler = new(HttpRequestResult(""));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        this._agentProvider.Verify(
+            p => p.CreateMessageAsync(It.IsAny<string>(), It.IsAny<ChatMessage>(), It.IsAny<CancellationToken>()),
+            Times.Never);
+    }
+
+    [Fact]
+    public async Task HttpGetReturnsJsonArrayAsync()
+    {
+        // Arrange - exercises JsonValueKind.Array branch of ParseResponseBody.
+        this.State.InitializeSystem();
+        const string ResponseVar = "Result";
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetReturnsJsonArrayAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            responseVariable: ResponseVar);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("[1, 2, 3]"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        FormulaValue stored = this.State.Get(ResponseVar);
+        Assert.IsType<TableValue>(stored, exactMatch: false);
+    }
+
+    [Fact]
+    public async Task HttpGetWithEmptyHeaderValueDropsHeaderAsync()
+    {
+        // Arrange - empty header values should be filtered out (matches GetHeaders guard).
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpGetWithEmptyHeaderValueDropsHeaderAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            headers: new Dictionary<string, string>
+            {
+                ["X-Trace"] = "trace-1",
+                ["X-Empty"] = "",
+            });
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info =>
+            info.Headers?.ContainsKey("X-Trace") == true &&
+            info.Headers?.ContainsKey("X-Empty") == false);
+    }
+
+    [Fact]
+    public async Task HttpRequestZeroTimeoutNotForwardedAsync()
+    {
+        // Arrange - non-positive timeouts should not be forwarded (handler default applies).
+        this.State.InitializeSystem();
+        HttpRequestAction model = this.CreateModel(
+            displayName: nameof(HttpRequestZeroTimeoutNotForwardedAsync),
+            url: TestUrl,
+            method: HttpMethodType.Get,
+            timeoutMilliseconds: 0);
+
+        MockHttpRequestHandler handler = new(HttpRequestResult("{}"));
+        HttpRequestExecutor action = new(model, handler.Object, this._agentProvider.Object, this.State);
+
+        // Act
+        await this.ExecuteAsync(action);
+
+        // Assert
+        VerifyModel(model, action);
+        handler.VerifySent(info => info.Timeout is null);
+    }
+
+    private static HttpRequestResult HttpRequestResult(
+        string? body,
+        int statusCode = 200,
+        bool isSuccess = true,
+        IReadOnlyDictionary<string, IReadOnlyList<string>>? headers = null) =>
+        new()
+        {
+            StatusCode = statusCode,
+            IsSuccessStatusCode = isSuccess,
+            Body = body,
+            Headers = headers,
+        };
+
+    private HttpRequestAction CreateModel(
+        string displayName,
+        string url,
+        HttpMethodType method,
+        string? responseVariable = null,
+        string? responseHeadersVariable = null,
+        IReadOnlyDictionary<string, string>? headers = null,
+        IReadOnlyDictionary<string, DataValue>? queryParameters = null,
+        string? conversationId = null,
+        string? connectionName = null,
+        DataValue? jsonBody = null,
+        string? rawBody = null,
+        string? rawContentType = null,
+        long? timeoutMilliseconds = null,
+        string? continueOnErrorStatusVariable = null,
+        string? continueOnErrorBodyVariable = null)
+    {
+        HttpRequestAction.Builder builder = new()
+        {
+            Id = this.CreateActionId(),
+            DisplayName = this.FormatDisplayName(displayName),
+            Url = new StringExpression.Builder(StringExpression.Literal(url)),
+            Method = new EnumExpression<HttpMethodTypeWrapper>.Builder(
+                EnumExpression<HttpMethodTypeWrapper>.Literal(HttpMethodTypeWrapper.Get(method))),
+        };
+
+        if (responseVariable is not null)
+        {
+            builder.Response = PropertyPath.Create(FormatVariablePath(responseVariable));
+        }
+
+        if (responseHeadersVariable is not null)
+        {
+            builder.ResponseHeaders = PropertyPath.Create(FormatVariablePath(responseHeadersVariable));
+        }
+
+        if (headers is not null)
+        {
+            foreach (KeyValuePair<string, string> header in headers)
+            {
+                builder.Headers.Add(header.Key, new StringExpression.Builder(StringExpression.Literal(header.Value)));
+            }
+        }
+
+        if (queryParameters is not null)
+        {
+            foreach (KeyValuePair<string, DataValue> parameter in queryParameters)
+            {
+                builder.QueryParameters.Add(parameter.Key, new ValueExpression.Builder(ValueExpression.Literal(parameter.Value)));
+            }
+        }
+
+        if (conversationId is not null)
+        {
+            builder.ConversationId = new StringExpression.Builder(StringExpression.Literal(conversationId));
+        }
+
+        if (connectionName is not null)
+        {
+            builder.Connection = new RemoteConnection.Builder
+            {
+                Name = new StringExpression.Builder(StringExpression.Literal(connectionName)),
+            };
+        }
+
+        if (jsonBody is not null)
+        {
+            builder.Body = new JsonRequestContent.Builder()
+            {
+                Content = new ValueExpression.Builder(ValueExpression.Literal(jsonBody)),
+            };
+        }
+        else if (rawBody is not null)
+        {
+            RawRequestContent.Builder rawBuilder = new()
+            {
+                Content = new StringExpression.Builder(StringExpression.Literal(rawBody)),
+            };
+            if (rawContentType is not null)
+            {
+                rawBuilder.ContentType = new StringExpression.Builder(StringExpression.Literal(rawContentType));
+            }
+            builder.Body = rawBuilder;
+        }
+
+        if (timeoutMilliseconds is not null)
+        {
+            builder.RequestTimeoutInMilliseconds = new IntExpression.Builder(IntExpression.Literal(timeoutMilliseconds.Value));
+        }
+
+        if (continueOnErrorStatusVariable is not null || continueOnErrorBodyVariable is not null)
+        {
+            ContinueOnErrorBehavior.Builder continueBuilder = new();
+            if (continueOnErrorStatusVariable is not null)
+            {
+                continueBuilder.StatusCode = PropertyPath.Create(FormatVariablePath(continueOnErrorStatusVariable));
+            }
+            if (continueOnErrorBodyVariable is not null)
+            {
+                continueBuilder.ErrorResponseBody = PropertyPath.Create(FormatVariablePath(continueOnErrorBodyVariable));
+            }
+            builder.ErrorHandling = continueBuilder;
+        }
+
+        return AssignParent<HttpRequestAction>(builder);
+    }
+
+    private sealed class MockHttpRequestHandler : Mock<IHttpRequestHandler>
+    {
+        private HttpRequestInfo? _lastRequest;
+
+        public MockHttpRequestHandler(HttpRequestResult result, Exception? throwOnSend = null)
+        {
+            this.Setup(handler => handler.SendAsync(It.IsAny<HttpRequestInfo>(), It.IsAny<CancellationToken>()))
+                .Returns<HttpRequestInfo, CancellationToken>((info, _) =>
+                {
+                    this._lastRequest = info;
+                    if (throwOnSend is not null)
+                    {
+                        throw throwOnSend;
+                    }
+                    return Task.FromResult(result);
+                });
+        }
+
+        public void VerifySent(Func<HttpRequestInfo, bool> predicate)
+        {
+            Assert.NotNull(this._lastRequest);
+            Assert.True(predicate(this._lastRequest!), "Sent HTTP request did not match expected predicate.");
+        }
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/Workflows/HttpRequest.yaml

@@ -0,0 +1,15 @@
+kind: Workflow
+trigger:
+
+  kind: OnConversationStart
+  id: my_workflow
+  actions:
+
+    - kind: HttpRequestAction
+      id: http_request
+      method: GET
+      url: =Concatenate("https://api.example.test/items/", System.LastMessageText)
+      headers:
+        Accept: application/json
+      response: Local.HttpResult
+      responseHeaders: Local.HttpHeaders

dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/SampleSmokeTest.cs

@@ -269,6 +269,29 @@ public class SampleSmokeTest
         _ = await Step9EntryPoint.RunAsync(writer, environment.ToWorkflowExecutionEnvironment());
     }
 
+    /// <summary>
+    /// Stress regression for the off-thread run-status race: after
+    /// <c>Run.ResumeAsync</c> returns at a halt boundary,
+    /// callers must observe a stable terminal status and never a transient
+    /// <see cref="RunStatus.Running"/>. Step9 is the canonical multi-response resume
+    /// sample; prior to the fix in <see cref="Execution.StreamingRunEventStream"/>,
+    /// its `runStatus.Should().Be(RunStatus.Idle)` assertion failed intermittently
+    /// on roughly 1-in-10 iterations under InProcess_OffThread.
+    /// </summary>
+    [Fact]
+    internal async Task Test_RunSample_Step9_OffThread_MultiResponseResume_StatusIsStableAsync()
+    {
+        const int Iterations = 50;
+
+        for (int i = 0; i < Iterations; i++)
+        {
+            using StringWriter writer = new();
+            _ = await Step9EntryPoint.RunAsync(
+                writer,
+                ExecutionEnvironment.InProcess_OffThread.ToWorkflowExecutionEnvironment());
+        }
+    }
+
     [Theory]
     [InlineData(ExecutionEnvironment.InProcess_Lockstep)]
     [InlineData(ExecutionEnvironment.InProcess_OffThread)]

python/.pre-commit-config.yaml

@@ -61,7 +61,7 @@ repos:
         additional_dependencies: ["bandit[toml]"]
   - repo: https://github.com/astral-sh/uv-pre-commit
     # uv version.
-    rev: 0.10.10
+    rev: 0.11.6
     hooks:
       # Update the uv lockfile
       - id: uv-lock

python/AGENTS.md

@@ -69,6 +69,7 @@ python/
 
 ### Azure Integrations
 - [foundry](packages/foundry/README.md) - Microsoft Foundry chat, agent, memory, and embedding integrations
+- [azure-contentunderstanding](packages/azure-contentunderstanding/AGENTS.md) - Azure Content Understanding context provider
 - [azure-ai-search](packages/azure-ai-search/AGENTS.md) - Azure AI Search RAG
 - [azure-cosmos](packages/azure-cosmos/AGENTS.md) - Azure Cosmos DB-backed history provider
 - [azurefunctions](packages/azurefunctions/AGENTS.md) - Azure Functions hosting

python/CHANGELOG.md

@@ -7,16 +7,76 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [1.2.2] - 2026-04-29
+
+### Added
+- **agent-framework-azure-contentunderstanding**: New alpha package — Azure AI Content Understanding context provider that auto-analyzes file attachments (documents, images, audio, video) and injects structured results into the LLM context, with multi-document session state, configurable timeout, output filtering via `AnalysisSection`, and auto-registered `list_documents` / `get_analyzed_document` tools ([#4829](https://github.com/microsoft/agent-framework/pull/4829))
+- **agent-framework-foundry-hosting**: Add hosted Durable Workflow support — propagate full conversation history to workflow agents and wire `Workflow.as_agent()` end-to-end via the foundry hosting layer ([#5531](https://github.com/microsoft/agent-framework/pull/5531))
+
+### Changed
+- **agent-framework-orchestrations**: [BREAKING] Standardize orchestration terminal outputs as `AgentResponse` so `Workflow.as_agent()` returns the final answer only; aligns sequential-approval (`with_request_info`) and concurrent (`intermediate_outputs=True`) flows on the same output contract ([#5301](https://github.com/microsoft/agent-framework/pull/5301))
+- **agent-framework-core**, **agent-framework-declarative**: Preserve `Workflow.run()` shared state across calls so multi-turn `WorkflowAgent` invocations retain context, accept `list[Message]` input in the declarative start executor, and coerce `Enum` values when serializing PowerFx symbols ([#5531](https://github.com/microsoft/agent-framework/pull/5531))
+- **dependencies**: Update workspace package dependencies and preserve `mcp[ws]` / `uvicorn[standard]` extras through override-dependencies in `/python` ([#5555](https://github.com/microsoft/agent-framework/pull/5555))
+
+### Fixed
+- **agent-framework-core**: Fix observability spans not being correctly nested when using streaming ([#5552](https://github.com/microsoft/agent-framework/pull/5552))
+- **agent-framework-openai**: Fix `file_search` citations breaking the assistant-message history roundtrip — skip `hosted_file` content in the assistant role so the Responses API no longer rejects `input_file` ([#5557](https://github.com/microsoft/agent-framework/pull/5557))
+
+## [1.2.1] - 2026-04-28
+
+### Added
+- **agent-framework-foundry-hosting**: Add file data type support to hosted-agent Responses, refresh `foundry-hosted-agents` samples, and add response test coverage ([#5485](https://github.com/microsoft/agent-framework/pull/5485))
+- **samples**: Add `requirements.txt` and `.env.example` to the `a2a/` hosting sample for pip-based setup ([#5510](https://github.com/microsoft/agent-framework/pull/5510))
+
+### Changed
+- **dependencies**: Update `rich` requirement from `<15.0.0,>=13.7.1` to `>=13.7.1,<16.0.0` in `/python` ([#5227](https://github.com/microsoft/agent-framework/pull/5227))
+- **dependencies**: Bump `prek` from `0.3.8` to `0.3.9` in `/python` ([#5228](https://github.com/microsoft/agent-framework/pull/5228))
+- **dependencies**: Bump `python-multipart` from `0.0.22` to `0.0.26` in `/python` ([#5286](https://github.com/microsoft/agent-framework/pull/5286))
+- **dependencies**: Bump `pyasn1` from `0.6.2` to `0.6.3` in `/python` ([#4748](https://github.com/microsoft/agent-framework/pull/4748))
+- **dependencies**: Bump `pytest` from `9.0.2` to `9.0.3` in `/python/packages/ag-ui` ([#5461](https://github.com/microsoft/agent-framework/pull/5461))
+- **dependencies**: Bump `pytest` from `9.0.2` to `9.0.3` in `/python/packages/devui` ([#5492](https://github.com/microsoft/agent-framework/pull/5492))
+- **dependencies**: Bump `pytest` from `9.0.2` to `9.0.3` in `/python/packages/lab` ([#5470](https://github.com/microsoft/agent-framework/pull/5470))
+- **dependencies**: Bump `uv` from `0.11.3` to `0.11.6` in `/python/packages/lab` ([#5469](https://github.com/microsoft/agent-framework/pull/5469))
+- **dependencies**: Bump `vite` from `7.1.12` to `7.3.2` in `/python/packages/devui/frontend` ([#5127](https://github.com/microsoft/agent-framework/pull/5127))
+- **dependencies**: Bump `vite` from `7.1.12` to `7.3.2` in `/python/samples/05-end-to-end/chatkit-integration/frontend` ([#5126](https://github.com/microsoft/agent-framework/pull/5126))
+- **dependencies**: Bump `postcss` from `8.5.6` to `8.5.10` in `/python/packages/devui/frontend` ([#5484](https://github.com/microsoft/agent-framework/pull/5484))
+- **dependencies**: Bump `postcss` from `8.5.6` to `8.5.10` in `/python/samples/05-end-to-end/chatkit-integration/frontend` ([#5491](https://github.com/microsoft/agent-framework/pull/5491))
+- **dependencies**: Bump `postcss` from `8.5.6` to `8.5.12` in `/python/samples/05-end-to-end/ag_ui_workflow_handoff/frontend` ([#5527](https://github.com/microsoft/agent-framework/pull/5527))
+- **dependencies**: Bump `picomatch` from `4.0.3` to `4.0.4` in `/python/packages/devui/frontend` ([#4921](https://github.com/microsoft/agent-framework/pull/4921))
+- **dependencies**: Bump `picomatch` from `4.0.3` to `4.0.4` in `/python/samples/05-end-to-end/ag_ui_workflow_handoff/frontend` ([#4936](https://github.com/microsoft/agent-framework/pull/4936))
+
+### Fixed
+- **agent-framework-core**: Prevent `inner_exception` from being lost in `AgentFrameworkException` ([#5167](https://github.com/microsoft/agent-framework/pull/5167))
+
+## [1.2.0] - 2026-04-24
+
+### Added
+- **agent-framework-core**: Add functional workflow API ([#4238](https://github.com/microsoft/agent-framework/pull/4238))
+- **agent-framework-core**, **agent-framework-github-copilot**: Add OpenTelemetry integration for `GitHubCopilotAgent` ([#5142](https://github.com/microsoft/agent-framework/pull/5142))
+- **agent-framework-a2a**: Add Agent Framework to A2A bridge support ([#2403](https://github.com/microsoft/agent-framework/pull/2403))
+- **agent-framework-foundry**: Surface `oauth_consent_request` events from Responses API in Foundry clients ([#5070](https://github.com/microsoft/agent-framework/pull/5070))
+
+### Changed
+- **agent-framework-core**, **agent-framework-foundry**: Update `FoundryAgent` for hosted agent sessions ([#5447](https://github.com/microsoft/agent-framework/pull/5447))
+- **agent-framework-foundry-hosting**: Upgrade hosting server dependency and add more type support ([#5459](https://github.com/microsoft/agent-framework/pull/5459))
+
+### Fixed
+- **agent-framework-ag-ui**: Fix reasoning role and multimodal media parsing to follow specification ([#5389](https://github.com/microsoft/agent-framework/pull/5389))
+- **agent-framework-foundry**: Stop emitting `[TOOLBOXES]` warning for every `FoundryChatClient` call ([#5440](https://github.com/microsoft/agent-framework/pull/5440))
+- **agent-framework-anthropic**, **agent-framework-azure-ai-search**, **agent-framework-azure-cosmos**: Fix user agent prefix ([#5455](https://github.com/microsoft/agent-framework/pull/5455))
+
 ## [1.1.1] - 2026-04-23
 
 ### Added
 - **agent-framework-core**: Add `expected_output` ground-truth support to `evaluate_workflow` for similarity evaluators ([#5234](https://github.com/microsoft/agent-framework/pull/5234))
 - **agent-framework-ag-ui**, **agent-framework-a2a**: Propagate `thread_id` and `forwarded_props` through AG-UI to A2A `context_id` ([#5383](https://github.com/microsoft/agent-framework/pull/5383))
 - **samples**: Add second approval-required tool (`set_stop_loss`) to `concurrent_builder_tool_approval` sample ([#4875](https://github.com/microsoft/agent-framework/pull/4875))
+- **agent-framework-core**: Add `SKIP_PARSING` sentinel for `FunctionTool.invoke` to bypass `Content`-wrapping and return raw function results ([#5424](https://github.com/microsoft/agent-framework/pull/5424))
 
 ### Changed
 - **agent-framework-foundry-hosting**: Correct Development Status classifier from Beta (4) to Alpha (3) to match the package's lifecycle stage ([#5387](https://github.com/microsoft/agent-framework/pull/5387))
 - **tests**: Add Python flaky test report workflow ([#5342](https://github.com/microsoft/agent-framework/pull/5342))
+- **agent-framework-hyperlight**: Simplify host callback to pass raw Python results via `SKIP_PARSING`, switch `execute_code` input schema to a plain JSON-schema dict, and tighten public API surface ([#5424](https://github.com/microsoft/agent-framework/pull/5424))
 
 ### Fixed
 - **agent-framework-openai**: Fix OpenAI Responses streaming to propagate `created_at` from the final `response.completed` event ([#5382](https://github.com/microsoft/agent-framework/pull/5382))
@@ -24,6 +84,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **agent-framework-openai**: Exclude null `file_id` from `input_image` payload to prevent schema 400 errors ([#5125](https://github.com/microsoft/agent-framework/pull/5125))
 - **agent-framework-foundry**: Reconcile Toolbox hosted-tool payloads with the Responses API ([#5414](https://github.com/microsoft/agent-framework/pull/5414))
 - **agent-framework-ag-ui**: Pass client `thread_id` as `session_id` when constructing `AgentSession` ([#5384](https://github.com/microsoft/agent-framework/pull/5384))
+- **agent-framework-hyperlight**: Thread-confine `WasmSandbox` interactions via per-entry `ThreadPoolExecutor` to eliminate the PyO3 `unsendable` panic when touched from asyncio worker threads ([#5424](https://github.com/microsoft/agent-framework/pull/5424))
 
 ## [1.1.0] - 2026-04-21
 
@@ -957,7 +1018,11 @@ Release candidate for **agent-framework-core** and **agent-framework-azure-ai**
 
 For more information, see the [announcement blog post](https://devblogs.microsoft.com/foundry/introducing-microsoft-agent-framework-the-open-source-engine-for-agentic-ai-apps/).
 
-[Unreleased]: https://github.com/microsoft/agent-framework/compare/python-1.1.0...HEAD
+[Unreleased]: https://github.com/microsoft/agent-framework/compare/python-1.2.2...HEAD
+[1.2.2]: https://github.com/microsoft/agent-framework/compare/python-1.2.1...python-1.2.2
+[1.2.1]: https://github.com/microsoft/agent-framework/compare/python-1.2.0...python-1.2.1
+[1.2.0]: https://github.com/microsoft/agent-framework/compare/python-1.1.1...python-1.2.0
+[1.1.1]: https://github.com/microsoft/agent-framework/compare/python-1.1.0...python-1.1.1
 [1.1.0]: https://github.com/microsoft/agent-framework/compare/python-1.0.1...python-1.1.0
 [1.0.1]: https://github.com/microsoft/agent-framework/compare/python-1.0.0...python-1.0.1
 [1.0.0]: https://github.com/microsoft/agent-framework/compare/python-1.0.0rc6...python-1.0.0

python/PACKAGE_STATUS.md

@@ -18,6 +18,7 @@ Status is grouped into these buckets:
 | `agent-framework-a2a` | `python/packages/a2a` | `beta` |
 | `agent-framework-ag-ui` | `python/packages/ag-ui` | `beta` |
 | `agent-framework-anthropic` | `python/packages/anthropic` | `beta` |
+| `agent-framework-azure-contentunderstanding` | `python/packages/azure-contentunderstanding` | `alpha` |
 | `agent-framework-azure-ai-search` | `python/packages/azure-ai-search` | `beta` |
 | `agent-framework-azure-cosmos` | `python/packages/azure-cosmos` | `beta` |
 | `agent-framework-azurefunctions` | `python/packages/azurefunctions` | `beta` |

python/packages/a2a/AGENTS.md

@@ -4,20 +4,48 @@ Agent-to-Agent (A2A) protocol support for inter-agent communication.
 
 ## Main Classes
 
-- **`A2AAgent`** - Agent wrapper that exposes an agent via the A2A protocol
+- **`A2AAgent`** - Client to connect to remote A2A-compliant agents.
+- **`A2AExecutor`** - Bridge to expose Agent Framework agents via the A2A protocol.
 
 ## Usage
 
+### A2AAgent (Client)
+
 ```python
 from agent_framework.a2a import A2AAgent
 
-a2a_agent = A2AAgent(agent=my_agent)
+# Connect to a remote A2A agent
+a2a_agent = A2AAgent(url="http://remote-agent/a2a")
+response = await a2a_agent.run("Hello!")
+```
+
+### A2AExecutor (Server/Bridge)
+
+```python
+from agent_framework.a2a import A2AExecutor
+from a2a.server.apps import A2AStarletteApplication
+from a2a.server.request_handlers import DefaultRequestHandler
+from a2a.server.tasks import InMemoryTaskStore
+
+# Create an A2A executor for your agent
+executor = A2AExecutor(agent=my_agent)
+
+# Set up the request handler and server application
+request_handler = DefaultRequestHandler(
+    agent_executor=executor,
+    task_store=InMemoryTaskStore(),
+)
+
+app = A2AStarletteApplication(
+    agent_card=my_agent_card,
+    http_handler=request_handler,
+).build()
 ```
 
 ## Import Path
 
 ```python
-from agent_framework.a2a import A2AAgent
+from agent_framework.a2a import A2AAgent, A2AExecutor
 # or directly:
-from agent_framework_a2a import A2AAgent
+from agent_framework_a2a import A2AAgent, A2AExecutor
 ```

python/packages/a2a/README.md

@@ -10,11 +10,49 @@ pip install agent-framework-a2a --pre
 
 The A2A agent integration enables communication with remote A2A-compliant agents using the standardized A2A protocol. This allows your Agent Framework applications to connect to agents running on different platforms, languages, or services.
 
+### A2AAgent (Client)
+
+The `A2AAgent` class is a client that wraps an A2A Client to connect the Agent Framework with external A2A-compliant agents.
+
+```python
+from agent_framework.a2a import A2AAgent
+
+# Connect to a remote A2A agent
+a2a_agent = A2AAgent(url="http://remote-agent/a2a")
+response = await a2a_agent.run("Hello!")
+```
+
+### A2AExecutor (Hosting)
+
+The `A2AExecutor` class bridges local AI agents built with the `agent_framework` library to the A2A protocol, allowing them to be hosted and accessed by other A2A-compliant clients.
+
+```python
+from agent_framework.a2a import A2AExecutor
+from a2a.server.apps import A2AStarletteApplication
+from a2a.server.request_handlers import DefaultRequestHandler
+from a2a.server.tasks import InMemoryTaskStore
+
+# Create an A2A executor for your agent
+executor = A2AExecutor(agent=my_agent)
+
+# Set up the request handler and server application
+request_handler = DefaultRequestHandler(
+    agent_executor=executor,
+    task_store=InMemoryTaskStore(),
+)
+
+app = A2AStarletteApplication(
+    agent_card=my_agent_card,
+    http_handler=request_handler,
+).build()
+```
+
 ### Basic Usage Example
 
 See the [A2A agent examples](../../samples/04-hosting/a2a/) which demonstrate:
 
 - Connecting to remote A2A agents
+- Hosting local agents via A2A protocol
 - Sending messages and receiving responses
 - Handling different content types (text, files, data)
 - Streaming responses and real-time interaction

python/packages/a2a/agent_framework_a2a/__init__.py

@@ -2,6 +2,7 @@
 
 import importlib.metadata
 
+from ._a2a_executor import A2AExecutor
 from ._agent import A2AAgent, A2AContinuationToken
 
 try:
@@ -12,5 +13,6 @@ except importlib.metadata.PackageNotFoundError:
 __all__ = [
     "A2AAgent",
     "A2AContinuationToken",
+    "A2AExecutor",
     "__version__",
 ]