build(deps): bump actions/cache from 4.3.0 to 5.0.5

Bumps [actions/cache](https://github.com/actions/cache) from 4.3.0 to 5.0.5. - [Release notes](https://github.com/actions/cache/releases) - [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md) - [Commits](https://github.com/actions/cache/compare/v4.3.0...27d5ce7f107fe9357f9df03efb73ab90386fccae) --- updated-dependencies: - dependency-name: actions/cache dependency-version: 5.0.5 dependency-type: direct:production update-type: version-update:semver-major ... Signed-off-by: dependabot[bot] <support@github.com>
2026-06-16 21:04:09 +08:00 · 2026-05-20 22:32:09 +00:00
164 changed files with 1107 additions and 12217 deletions
@@ -602,7 +602,7 @@ jobs:
          pattern: dotnet-test-results-*
          path: dotnet-test-results/
      - name: Restore report history cache
-        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/dotnet-integration-report-history.json
          key: dotnet-integration-report-history-${{ github.run_id }}
@@ -619,7 +619,7 @@ jobs:
        run: cat dotnet-integration-test-report.md >> $GITHUB_STEP_SUMMARY
      - name: Save report history cache
        if: always()
-        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/dotnet-integration-report-history.json
          key: dotnet-integration-report-history-${{ github.run_id }}
@@ -137,7 +137,6 @@ jobs:
        working-directory: ${{ env.DEVFLOW_PATH }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          DEVFLOW_TOKEN: ${{ secrets.DEVFLOW_TOKEN }}
          SK_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          AGENT_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          ISSUE_REPO: ${{ needs.team_check.outputs.repo }}
@@ -177,7 +177,7 @@ jobs:
        run: curl -fsSL https://ollama.com/install.sh | sh
        working-directory: .
      - name: Cache Ollama models
-        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: ~/.ollama/models
          key: ollama-models-qwen2.5-1.5b-nomic-embed-text-v1
@@ -511,7 +511,7 @@ jobs:
          pattern: test-results-*
          path: test-results/
      - name: Restore report history cache
-        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/integration-report-history.json
          key: integration-report-history-integration-${{ github.run_id }}
@@ -528,7 +528,7 @@ jobs:
        run: cat integration-test-report.md >> $GITHUB_STEP_SUMMARY
      - name: Save report history cache
        if: always()
-        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/integration-report-history.json
          key: integration-report-history-integration-${{ github.run_id }}
@@ -295,7 +295,7 @@ jobs:
        run: curl -fsSL https://ollama.com/install.sh | sh
        working-directory: .
      - name: Cache Ollama models
-        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: ~/.ollama/models
          key: ollama-models-qwen2.5-1.5b-nomic-embed-text-v1
@@ -692,7 +692,7 @@ jobs:
          pattern: test-results-*
          path: test-results/
      - name: Restore report history cache
-        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/integration-report-history.json
          key: integration-report-history-merge-${{ github.run_id }}
@@ -709,7 +709,7 @@ jobs:
        run: cat integration-test-report.md >> $GITHUB_STEP_SUMMARY
      - name: Save report history cache
        if: always()
-        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: python/integration-report-history.json
          key: integration-report-history-merge-${{ github.run_id }}
@@ -701,7 +701,7 @@ jobs:

      - name: Restore validation history
        id: cache-restore
-        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: validation-history/
          key: validation-history-${{ github.run_id }}
@@ -719,7 +719,7 @@ jobs:
        run: cat trend-report.md >> "$GITHUB_STEP_SUMMARY"

      - name: Save validation history
-        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
        with:
          path: validation-history/
          key: validation-history-${{ github.run_id }}
@@ -121,7 +121,6 @@
  <Folder Name="/Samples/02-agents/Harness/">
    <File Path="samples/02-agents/Harness/README.md" />
    <Project Path="samples/02-agents/Harness/Harness_Shared_Console/Harness_Shared_Console.csproj" />
-    <Project Path="samples/02-agents/Harness/Harness_Shared_Console_OpenAI/Harness_Shared_Console_OpenAI.csproj" />
    <Project Path="samples/02-agents/Harness/Harness_Step01_Research/Harness_Step01_Research.csproj" />
    <Project Path="samples/02-agents/Harness/Harness_Step02_Research_WithBackgroundAgents/Harness_Step02_Research_WithBackgroundAgents.csproj" />
    <Project Path="samples/02-agents/Harness/Harness_Step03_DataProcessing/Harness_Step03_DataProcessing.csproj" />
@@ -212,7 +211,6 @@
  </Folder>
  <Folder Name="/Samples/02-agents/ModelContextProtocol/">
    <File Path="samples/02-agents/ModelContextProtocol/README.md" />
-    <Project Path="samples/02-agents/ModelContextProtocol/Agent_MCP_LongRunningTask_Client/Agent_MCP_LongRunningTask_Client.csproj" />
    <Project Path="samples/02-agents/ModelContextProtocol/Agent_MCP_Server/Agent_MCP_Server.csproj" />
    <Project Path="samples/02-agents/ModelContextProtocol/Agent_MCP_Server_Auth/Agent_MCP_Server_Auth.csproj" />
    <Project Path="samples/02-agents/ModelContextProtocol/FoundryAgent_Hosted_MCP/FoundryAgent_Hosted_MCP.csproj" />
@@ -282,7 +280,6 @@
  </Folder>
  <Folder Name="/Samples/03-workflows/Orchestration/">
    <Project Path="samples/03-workflows/Orchestration/Handoff/Handoff.csproj" />
-    <Project Path="samples/03-workflows/Orchestration/Magentic/Magentic.csproj" />
  </Folder>
  <Folder Name="/Samples/03-workflows/Observability/">
    <Project Path="samples/03-workflows/Observability/ApplicationInsights/ApplicationInsights.csproj" />
@@ -603,7 +600,6 @@
    <Project Path="src/Microsoft.Agents.AI.Hosting.OpenAI/Microsoft.Agents.AI.Hosting.OpenAI.csproj" />
    <Project Path="src/Microsoft.Agents.AI.Hosting/Microsoft.Agents.AI.Hosting.csproj" />
    <Project Path="src/Microsoft.Agents.AI.Hyperlight/Microsoft.Agents.AI.Hyperlight.csproj" />
-    <Project Path="src/Microsoft.Agents.AI.Mcp/Microsoft.Agents.AI.Mcp.csproj" />
    <Project Path="src/Microsoft.Agents.AI.Mem0/Microsoft.Agents.AI.Mem0.csproj" />
    <Project Path="src/Microsoft.Agents.AI.OpenAI/Microsoft.Agents.AI.OpenAI.csproj" />
    <Project Path="src/Microsoft.Agents.AI.Purview/Microsoft.Agents.AI.Purview.csproj" />
@@ -657,7 +653,6 @@
    <Project Path="tests/Microsoft.Agents.AI.Hosting.OpenAI.UnitTests/Microsoft.Agents.AI.Hosting.OpenAI.UnitTests.csproj" />
    <Project Path="tests/Microsoft.Agents.AI.Hosting.UnitTests/Microsoft.Agents.AI.Hosting.UnitTests.csproj" />
    <Project Path="tests/Microsoft.Agents.AI.Hyperlight.UnitTests/Microsoft.Agents.AI.Hyperlight.UnitTests.csproj" />
-    <Project Path="tests/Microsoft.Agents.AI.Mcp.UnitTests/Microsoft.Agents.AI.Mcp.UnitTests.csproj" />
    <Project Path="tests/Microsoft.Agents.AI.Mem0.UnitTests/Microsoft.Agents.AI.Mem0.UnitTests.csproj" />
    <Project Path="tests/Microsoft.Agents.AI.OpenAI.UnitTests/Microsoft.Agents.AI.OpenAI.UnitTests.csproj" />
    <Project Path="tests/Microsoft.Agents.AI.Purview.UnitTests/Microsoft.Agents.AI.Purview.UnitTests.csproj" />
@@ -1151,25 +1151,6 @@ internal static class AgentsSamples
            SkipReason = "Runs as an MCP stdio server that does not exit on its own.",
        },

-        new SampleDefinition
-        {
-            Name = "Agent_MCP_LongRunningTask_Client",
-            ProjectPath = "samples/02-agents/ModelContextProtocol/Agent_MCP_LongRunningTask_Client",
-            RequiredEnvironmentVariables = ["AZURE_OPENAI_ENDPOINT"],
-            OptionalEnvironmentVariables = ["AZURE_OPENAI_DEPLOYMENT_NAME"],
-            MustContain =
-            [
-                "=== Transparent long-running MCP task (RunAsync) ===",
-                "=== Transparent long-running MCP task (RunStreamingAsync) ===",
-            ],
-            ExpectedOutputDescription =
-            [
-                "The output should show an agent analyzing a dataset named 'sales-2025-q1' and producing a summary mentioning rows, revenue, anomalies, or outliers.",
-                "The output should contain both a non-streaming response (after RunAsync) and a streaming response (after RunStreamingAsync) for the same analysis question.",
-                "The output should not contain error messages or stack traces.",
-            ],
-        },
-
        new SampleDefinition
        {
            Name = "AGUI_Step01_GettingStarted_Client",
@@ -1,14 +1,14 @@
 <Project>
  <PropertyGroup>
    <!-- Central version prefix - applies to all nuget packages. -->
-    <VersionPrefix>1.6.2</VersionPrefix>
+    <VersionPrefix>1.6.1</VersionPrefix>
    <RCNumber>1</RCNumber>
-    <DateSuffix>260521</DateSuffix>
+    <DateSuffix>260514</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>1.6.2</GitTag>
+    <GitTag>1.6.1</GitTag>

    <Configurations>Debug;Release;Publish</Configurations>
    <IsPackable>true</IsPackable>
@@ -192,11 +192,6 @@ public sealed class HarnessAgentRunner : IDisposable
                        }
                    }

-                    foreach (var observer in this._observers)
-                    {
-                        await observer.OnResponseUpdateAsync(this._ux, update, this._agent, this._session).ConfigureAwait(false);
-                    }
-
                    if (!string.IsNullOrEmpty(update.Text))
                    {
                        foreach (var observer in this._observers)
@@ -24,17 +24,6 @@ public abstract class ConsoleObserver
    {
    }

-    /// <summary>
-    /// Called for each <see cref="AgentResponseUpdate"/> in the response stream, regardless of
-    /// whether it contains content. Override to inspect update-level metadata such as
-    /// <see cref="AgentResponseUpdate.RawRepresentation"/> for provider-specific events.
-    /// </summary>
-    /// <param name="ux">The UX state driver, used for rendering output.</param>
-    /// <param name="update">The streaming response update.</param>
-    /// <param name="agent">The agent being interacted with.</param>
-    /// <param name="session">The current agent session.</param>
-    public virtual Task OnResponseUpdateAsync(IUXStateDriver ux, AgentResponseUpdate update, AIAgent agent, AgentSession session) => Task.CompletedTask;
-
    /// <summary>
    /// Called for each <see cref="AIContent"/> item in the response stream.
    /// </summary>
@@ -1,19 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFrameworks>net10.0</TargetFrameworks>
-
-    <Nullable>enable</Nullable>
-    <ImplicitUsings>enable</ImplicitUsings>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="OpenAI" />
-    <PackageReference Include="Microsoft.Extensions.AI" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <ProjectReference Include="..\Harness_Shared_Console\Harness_Shared_Console.csproj" />
-  </ItemGroup>
-
-</Project>
@@ -1,61 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-#pragma warning disable OPENAI001 // Suppress experimental API warnings for Responses API usage.
-
-using Harness.Shared.Console.Observers;
-using Microsoft.Agents.AI;
-using Microsoft.Extensions.AI;
-using OpenAI.Responses;
-
-namespace Harness.Shared.Console.OpenAI;
-
-/// <summary>
-/// Detects and displays error/incomplete status from OpenAI Responses API streaming updates.
-/// Handles <see cref="StreamingResponseFailedUpdate"/> and <see cref="StreamingResponseIncompleteUpdate"/>
-/// which are not surfaced as <see cref="ErrorContent"/> by the chat client.
-/// </summary>
-/// <remarks>
-/// Note: <see cref="StreamingResponseErrorUpdate"/> is already handled by the SDK — it produces
-/// an <see cref="ErrorContent"/> which is displayed by <see cref="ErrorDisplayObserver"/>.
-/// This observer covers the cases where the SDK does not produce <see cref="ErrorContent"/>.
-/// </remarks>
-public sealed class OpenAIResponsesErrorObserver : ConsoleObserver
-{
-    /// <inheritdoc/>
-    public override async Task OnResponseUpdateAsync(IUXStateDriver ux, AgentResponseUpdate update, AIAgent agent, AgentSession session)
-    {
-        // AgentResponseUpdate.RawRepresentation is the ChatResponseUpdate,
-        // whose RawRepresentation is the underlying StreamingResponseUpdate.
-        object? rawUpdate = (update.RawRepresentation as ChatResponseUpdate)?.RawRepresentation
-            ?? update.RawRepresentation;
-
-        switch (rawUpdate)
-        {
-            case StreamingResponseFailedUpdate failedUpdate:
-                // Only display if the response has error details populated.
-                // When error is null, a follow-up StreamingResponseErrorUpdate typically
-                // carries the real error — the SDK surfaces that as ErrorContent,
-                // which is displayed by ErrorDisplayObserver.
-                if (failedUpdate.Response?.Error is { } error)
-                {
-                    string errorMessage = error.Message ?? "Unknown error";
-                    string? errorCode = error.Code.ToString();
-                    string errorText = $"❌ Response failed: {errorMessage}";
-                    if (!string.IsNullOrEmpty(errorCode))
-                    {
-                        errorText += $" (code: {errorCode})";
-                    }
-
-                    await ux.WriteInfoLineAsync(errorText, ConsoleColor.Red);
-                }
-
-                break;
-
-            case StreamingResponseIncompleteUpdate incompleteUpdate:
-                string? reason = incompleteUpdate.Response?.IncompleteStatusDetails?.Reason?.ToString();
-                string incompleteText = $"⚠️ Response incomplete: {reason ?? "unknown reason"}";
-                await ux.WriteInfoLineAsync(incompleteText, ConsoleColor.Yellow);
-                break;
-        }
-    }
-}
@@ -16,7 +16,6 @@
    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Foundry\Microsoft.Agents.AI.Foundry.csproj" />
    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Harness\Microsoft.Agents.AI.Harness.csproj" />
    <ProjectReference Include="..\Harness_Shared_Console\Harness_Shared_Console.csproj" />
-    <ProjectReference Include="..\Harness_Shared_Console_OpenAI\Harness_Shared_Console_OpenAI.csproj" />
  </ItemGroup>

 </Project>
@@ -3,18 +3,19 @@
 #pragma warning disable OPENAI001 // Suppress experimental API warnings for Responses API usage.

 using System.Text;
+using Harness.Shared.Console;
 using Harness.Shared.Console.Observers;
 using Microsoft.Agents.AI;
 using Microsoft.Extensions.AI;
 using OpenAI.Responses;

-namespace Harness.Shared.Console.OpenAI;
+namespace SampleApp;

 /// <summary>
 /// Displays web search activity in the scroll area. Shows search queries,
 /// page opens, and find-in-page actions as they stream in from the API.
 /// </summary>
-public sealed class OpenAIResponsesWebSearchDisplayObserver : ConsoleObserver
+internal sealed class OpenAIResponsesWebSearchDisplayObserver : ConsoleObserver
 {
    private const int MaxQueryDisplayLength = 120;

@@ -19,7 +19,6 @@ using System.ClientModel.Primitives;
 using Azure.AI.Projects;
 using Azure.Identity;
 using Harness.Shared.Console;
-using Harness.Shared.Console.OpenAI;
 using Harness.Shared.Console.ToolFormatters;
 using Microsoft.Agents.AI;
 using Microsoft.Extensions.AI;
@@ -108,7 +107,6 @@ await HarnessConsole.RunAgentAsync(
    {
        Observers = [
            new OpenAIResponsesWebSearchDisplayObserver(),
-            new OpenAIResponsesErrorObserver(),
            .. HarnessConsoleOptions.BuildObserversWithPlanning(
                agent,
                planModeName: "plan",
@@ -16,7 +16,6 @@
    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Foundry\Microsoft.Agents.AI.Foundry.csproj" />
    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Harness\Microsoft.Agents.AI.Harness.csproj" />
    <ProjectReference Include="..\Harness_Shared_Console\Harness_Shared_Console.csproj" />
-    <ProjectReference Include="..\Harness_Shared_Console_OpenAI\Harness_Shared_Console_OpenAI.csproj" />
  </ItemGroup>

 </Project>
@@ -16,7 +16,6 @@ using System.ClientModel.Primitives;
 using Azure.AI.Projects;
 using Azure.Identity;
 using Harness.Shared.Console;
-using Harness.Shared.Console.OpenAI;
 using Microsoft.Agents.AI;
 using Microsoft.Extensions.AI;

@@ -103,7 +102,10 @@ AIAgent parentAgent =
        DisableFileAccess = true,   // If enabled, this would allow the agent to read/write files in a working directory
        DisableToolApproval = true, // If enabled, this allows don't-ask-again approval functionality.
        DisableWebSearch = true,
-        BackgroundAgents = [webSearchAgent],
+        AIContextProviders =
+        [
+            new BackgroundAgentsProvider([webSearchAgent]),
+        ],
        ChatOptions = new ChatOptions
        {
            Instructions = parentInstructions,
@@ -114,8 +116,4 @@ AIAgent parentAgent =
 // Run the interactive console session.
 await HarnessConsole.RunAgentAsync(
    parentAgent,
-    userPrompt: "Enter a list of stock tickers (e.g., BAC, MSFT, BA):",
-    options: new HarnessConsoleOptions
-    {
-        Observers = [new OpenAIResponsesErrorObserver(), .. HarnessConsoleOptions.BuildDefaultObservers()],
-    });
+    userPrompt: "Enter a list of stock tickers (e.g., BAC, MSFT, BA):");
@@ -1,25 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <OutputType>Exe</OutputType>
-    <TargetFrameworks>net10.0</TargetFrameworks>
-
-    <Nullable>enable</Nullable>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <NoWarn>$(NoWarn);MAAI001;MEAI001;MCPEXP001</NoWarn>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Azure.AI.OpenAI" />
-    <PackageReference Include="Azure.Identity" />
-    <PackageReference Include="Microsoft.Extensions.AI.OpenAI" />
-    <PackageReference Include="Microsoft.Extensions.Hosting" />
-    <PackageReference Include="ModelContextProtocol" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Mcp\Microsoft.Agents.AI.Mcp.csproj" />
-    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.OpenAI\Microsoft.Agents.AI.OpenAI.csproj" />
-  </ItemGroup>
-
-</Project>
@@ -1,145 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-// This sample demonstrates the Microsoft Agent Framework's MCP long-running task support.
-//
-// A small MCP server (hosted in this same executable when launched with "--server") exposes
-// a single task-supporting tool "AnalyzeDataset" that simulates ~15 seconds of work. The
-// client (default mode) connects to it over stdio via Microsoft.Agents.AI.Mcp's
-// McpClientTaskExtensions.ListAgentToolsWithTaskSupportAsync, hands the wrapped tools to a
-// ChatClientAgent, and exercises both invocation styles:
-//   * RunAsync          — blocks until the agent's final response is ready.
-//   * RunStreamingAsync — yields response updates as the model produces them; the model
-//                         still waits for the tool's terminal result before it can begin
-//                         producing the final answer, so the perceived "pause" reflects
-//                         tool execution time, not stream-channel latency.
-//
-// In both cases the wrapper transparently:
-//   1. Calls tools/call with task augmentation (CallToolAsTaskAsync)
-//   2. Polls tasks/get until terminal (PollTaskUntilCompleteAsync)
-//   3. Fetches tasks/result and returns the final result to the function-calling loop
-//
-// No application-level loop or continuation tokens are required in either mode.
-
-using System.ComponentModel;
-using Azure.AI.OpenAI;
-using Azure.Identity;
-using Microsoft.Agents.AI;
-using Microsoft.Agents.AI.Mcp;
-using Microsoft.Extensions.AI;
-using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.Hosting;
-using Microsoft.Extensions.Logging;
-using ModelContextProtocol;
-using ModelContextProtocol.Client;
-using ModelContextProtocol.Protocol;
-using ModelContextProtocol.Server;
-using OpenAI.Chat;
-
-if (args.Length > 0 && args[0] == "--server")
-{
-    await RunMcpServerAsync();
-    return;
-}
-
-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";
-
-// Launch this same assembly as a stdio MCP server in a child process.
-var thisAssemblyPath = typeof(Program).Assembly.Location;
-await using var mcpClient = await McpClient.CreateAsync(new StdioClientTransport(new()
-{
-    Name = "DatasetAnalyzer",
-    Command = "dotnet",
-    Arguments = [thisAssemblyPath, "--server"],
-}));
-
-// Wrap each MCP tool with task-aware behavior. The wrapper inspects the server's
-// execution.taskSupport on each tool and, when it is Required, drives the task lifecycle
-// transparently within the agent's tool loop. Tools that don't require task semantics are
-// returned as-is and invoked inline.
-var taskOptions = new McpTaskOptions
-{
-    DefaultTimeToLive = TimeSpan.FromMinutes(5),
-};
-var mcpTools = await mcpClient.ListAgentToolsWithTaskSupportAsync(taskOptions);
-
-// 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)
-     .AsAIAgent(
-        instructions: "You answer data-analysis questions by invoking the available tools. Always invoke a tool when one matches the request.",
-        tools: [.. mcpTools.Cast<AITool>()]);
-
-const string Prompt = "Analyze the dataset named 'sales-2025-q1' and summarize the findings.";
-
-Console.WriteLine("=== Transparent long-running MCP task (RunAsync) ===");
-Console.WriteLine("Asking the agent to analyze a dataset; the tool takes ~15s to complete.");
-Console.WriteLine("RunAsync blocks while the wrapper polls the task to completion.");
-Console.WriteLine();
-
-var stopwatch = System.Diagnostics.Stopwatch.StartNew();
-var response = await agent.RunAsync(Prompt);
-stopwatch.Stop();
-
-Console.WriteLine($"Agent response (after {stopwatch.Elapsed.TotalSeconds:F1}s):");
-Console.WriteLine(response.Text);
-
-Console.WriteLine();
-Console.WriteLine("=== Transparent long-running MCP task (RunStreamingAsync) ===");
-Console.WriteLine("Same request via the streaming API. Updates only begin to arrive after the");
-Console.WriteLine("tool's task reaches the Completed state, since the model needs the tool result");
-Console.WriteLine("before it can produce its final answer.");
-Console.WriteLine();
-
-stopwatch.Restart();
-await foreach (var update in agent.RunStreamingAsync(Prompt))
-{
-    Console.Write(update.Text);
-}
-stopwatch.Stop();
-
-Console.WriteLine();
-Console.WriteLine($"(Streaming completed after {stopwatch.Elapsed.TotalSeconds:F1}s.)");
-
-// --- Server mode (launched as a child process via --server) ---------------------------------
-static async Task RunMcpServerAsync()
-{
-    var builder = Host.CreateApplicationBuilder();
-
-    // Critical for stdio transport: any provider that writes to stdout will corrupt the
-    // JSON-RPC channel. Clear all providers; the MCP SDK routes its own diagnostics
-    // appropriately.
-    builder.Logging.ClearProviders();
-    builder.Logging.AddConsole(o => o.LogToStandardErrorThreshold = LogLevel.Trace);
-
-    builder.Services.AddMcpServer(o =>
-    {
-        o.TaskStore = new InMemoryMcpTaskStore();
-        o.ServerInfo = new Implementation { Name = "DatasetAnalyzer", Version = "1.0.0" };
-    })
-    .WithStdioServerTransport()
-    .WithTools<DatasetAnalysisTools>();
-
-    await builder.Build().RunAsync();
-}
-
-#pragma warning disable CA1812 // Discovered by MCP SDK via [McpServerToolType] attribute
-[McpServerToolType]
-internal sealed class DatasetAnalysisTools
-#pragma warning restore CA1812
-{
-    [McpServerTool(Name = "AnalyzeDataset", TaskSupport = ToolTaskSupport.Required)]
-    [Description("Analyze a tabular dataset and return summary statistics. This tool simulates a long-running analytic job (~15 seconds).")]
-    public static async Task<string> AnalyzeDatasetAsync(
-        [Description("The dataset identifier, e.g. 'sales-2025-q1'.")] string datasetName,
-        CancellationToken cancellationToken)
-    {
-        await Task.Delay(TimeSpan.FromSeconds(15), cancellationToken).ConfigureAwait(false);
-
-        return $"Findings for '{datasetName}': 12,403 rows; avg revenue $48,712; 3 anomalies detected in week 7; outliers concentrated in EMEA region.";
-    }
-}
@@ -1,60 +0,0 @@
-# Agent with MCP long-running task (transparent polling)
-
-This sample demonstrates Microsoft Agent Framework's MCP long-running task support: an agent invokes an MCP tool whose execution takes too long for a single request/response cycle, and the framework polls it to completion behind the function-calling loop. From the agent's perspective the tool simply returns its result.
-
-## What this sample shows
-
- Using `McpClient.ListAgentToolsWithTaskSupportAsync(...)` (in `Microsoft.Agents.AI.Mcp`) to wrap MCP tools with task-aware behavior.
- Configuring `McpTaskOptions.DefaultTimeToLive` to bound the server-side task.
- Hosting a small MCP server (in this same executable, launched with `--server`) that advertises `execution.taskSupport=required` on a tool that sleeps for ~15 seconds.
- No application-level polling, continuation tokens, or `AllowBackgroundResponses` flag are required.
-
-The decorator drives the lifecycle internally:
-
-1. `tools/call` augmented with task metadata (`CallToolAsTaskAsync`)
-2. `tasks/get` polled until terminal (`PollTaskUntilCompleteAsync`)
-3. `tasks/result` retrieved (`GetTaskResultAsync`) and returned to the function-calling loop
-
-The sample exercises both invocation styles against the same wrapper:
-
- `agent.RunAsync(...)` blocks until the tool completes (~15 seconds in this sample) and returns the final response.
- `agent.RunStreamingAsync(...)` returns immediately and yields `AgentResponseUpdate` chunks as the model emits them; in this scenario the model only begins streaming its answer once the wrapped tool's task reaches the `Completed` state, so the perceived "pause" before tokens arrive reflects tool execution time, not stream-channel latency.
-
-# Prerequisites
-
- .NET 10 SDK or later
- Azure OpenAI service endpoint and a chat-completions deployment
- Azure CLI installed and authenticated (`az login`)
-
-Set the following 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
-```
-
-# Running
-
-```powershell
-cd Agent_MCP_LongRunningTask_Client
-dotnet run
-```
-
-You should see output similar to:
-
-```
-=== Transparent long-running MCP task (RunAsync) ===
-Asking the agent to analyze a dataset; the tool takes ~15s to complete.
-RunAsync blocks while the wrapper polls the task to completion.
-
-Agent response (after 15.4s):
-The 'sales-2025-q1' dataset contains 12,403 rows ...
-
-=== Transparent long-running MCP task (RunStreamingAsync) ===
-Same request via the streaming API. Updates only begin to arrive after the
-tool's task reaches the Completed state, since the model needs the tool result
-before it can produce its final answer.
-
-The 'sales-2025-q1' dataset contains 12,403 rows ...
-(Streaming completed after 15.7s.)
-```
@@ -22,7 +22,6 @@ Before you begin, ensure you have the following prerequisites:
 |[Agent with MCP server tools](./Agent_MCP_Server/)|This sample demonstrates how to use MCP server tools with a simple agent|
 |[Agent with MCP server tools and authorization](./Agent_MCP_Server_Auth/)|This sample demonstrates how to use MCP Server tools from a protected MCP server with a simple agent|
 |[Responses Agent with Hosted MCP tool](./ResponseAgent_Hosted_MCP/)|This sample demonstrates how to use the Hosted MCP tool with the Responses Service, where the service invokes any MCP tools directly|
-|[Agent with long-running MCP task (transparent polling)](./Agent_MCP_LongRunningTask_Client/)|This sample demonstrates how an agent transparently drives a long-running MCP task (SEP-2663) to completion. The wrapper polls the task internally on both `RunAsync` and `RunStreamingAsync` invocations.|

 ## Running the samples from the console

@@ -1,23 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <OutputType>Exe</OutputType>
-    <TargetFrameworks>net10.0</TargetFrameworks>
-
-    <Nullable>enable</Nullable>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <NoWarn>$(NoWarn);MAAIW001;OPENAI001</NoWarn>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Azure.AI.Projects" />
-    <PackageReference Include="Azure.Identity" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Workflows\Microsoft.Agents.AI.Workflows.csproj" />
-    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI.Foundry\Microsoft.Agents.AI.Foundry.csproj" />
-    <ProjectReference Include="..\..\..\..\src\Microsoft.Agents.AI\Microsoft.Agents.AI.csproj" />
-  </ItemGroup>
-
-</Project>
@@ -1,193 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-// This sample ports the Python Magentic orchestration sample to .NET.
-// A Magentic workflow coordinates a researcher and a coder, streams orchestration
-// events as the plan evolves, and prints the final conversation transcript.
-
-using Azure.AI.Projects;
-using Azure.Identity;
-using Microsoft.Agents.AI;
-using Microsoft.Agents.AI.Workflows;
-using Microsoft.Agents.AI.Workflows.Specialized.Magentic;
-using Microsoft.Extensions.AI;
-
-namespace WorkflowMagenticOrchestrationSample;
-
-/// <summary>
-/// Demonstrates Magentic orchestration with a researcher, a coder, and an LLM manager.
-/// </summary>
-/// <remarks>
-/// Pre-requisites:
-/// - An Azure AI Foundry project endpoint and model deployment must be configured.
-/// - Run <c>az login</c> before executing the sample.
-/// </remarks>
-public static class Program
-{
-    private const string TaskPrompt =
-        "I am preparing a report on the energy efficiency of different machine learning model architectures. " +
-        "Compare the estimated training and inference energy consumption of ResNet-50, BERT-base, and GPT-2 " +
-        "on standard datasets (e.g., ImageNet for ResNet, GLUE for BERT, WebText for GPT-2). " +
-        "Then, estimate the CO2 emissions associated with each, assuming training on an Azure Standard_NC6s_v3 " +
-        "VM for 24 hours. Provide tables for clarity, and recommend the most energy-efficient model " +
-        "per task type (image classification, text classification, and text generation).";
-
-    private static async Task Main()
-    {
-        string endpoint = Environment.GetEnvironmentVariable("AZURE_AI_PROJECT_ENDPOINT")
-            ?? throw new InvalidOperationException("AZURE_AI_PROJECT_ENDPOINT is not set.");
-        string deploymentName = Environment.GetEnvironmentVariable("AZURE_AI_MODEL_DEPLOYMENT_NAME") ?? "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.
-        AIProjectClient projectClient = new(new Uri(endpoint), new DefaultAzureCredential());
-
-        AIAgent researcherAgent = projectClient.AsAIAgent(
-            deploymentName,
-            name: "ResearcherAgent",
-            description: "Specialist in research and information gathering.",
-            instructions: "You are a researcher. Find relevant information without doing additional computation or quantitative analysis.");
-
-        AIAgent coderAgent = projectClient.AsAIAgent(
-            deploymentName,
-            name: "CoderAgent",
-            description: "A helpful assistant that writes and executes code to analyze data.",
-            instructions: "You solve quantitative questions by writing and running code. Show the analysis and the computation process clearly.",
-            tools: [new HostedCodeInterpreterTool()]);
-
-        AIAgent managerAgent = projectClient.AsAIAgent(
-            deploymentName,
-            name: "MagenticManager",
-            description: "Orchestrator that coordinates the research and coding workflow.",
-            instructions: "You coordinate the team to complete complex tasks efficiently.");
-
-        Workflow workflow = new MagenticWorkflowBuilder(managerAgent)
-            .AddParticipants([researcherAgent, coderAgent])
-            .WithName("Magentic Orchestration Workflow")
-            .WithDescription("Coordinates a researcher and coder to solve a complex analytical task.")
-            .RequirePlanSignoff(false)
-            .WithMaxRounds(10)
-            .WithMaxStalls(3)
-            .WithMaxResets(2)
-            .Build();
-
-        Console.WriteLine("Building Magentic workflow...");
-        Console.WriteLine();
-        Console.WriteLine($"Task: {TaskPrompt}");
-        Console.WriteLine();
-        Console.WriteLine("Starting workflow execution...");
-
-        await using StreamingRun run = await InProcessExecution.RunStreamingAsync(
-            workflow,
-            new List<ChatMessage> { new(ChatRole.User, TaskPrompt) });
-
-        await run.TrySendMessageAsync(new TurnToken(emitEvents: true));
-
-        string? lastResponseId = null;
-        WorkflowOutputEvent? finalOutput = null;
-
-        await foreach (WorkflowEvent workflowEvent in run.WatchStreamAsync())
-        {
-            switch (workflowEvent)
-            {
-                case AgentResponseUpdateEvent updateEvent:
-                    WriteStreamingUpdate(updateEvent, ref lastResponseId);
-                    break;
-
-                case MagenticPlanCreatedEvent planCreated:
-                    WriteMagenticMessage("Initial Plan", planCreated.FullTaskLedger.Text);
-                    PauseIfInteractive();
-                    break;
-
-                case MagenticReplannedEvent replanned:
-                    WriteMagenticMessage("Replanned", replanned.FullTaskLedger.Text);
-                    PauseIfInteractive();
-                    break;
-
-                case MagenticProgressLedgerUpdatedEvent progressUpdated:
-                    WriteMagenticMessage("Progress Ledger", FormatProgressLedger(progressUpdated.ProgressLedger));
-                    PauseIfInteractive();
-                    break;
-
-                case WorkflowOutputEvent outputEvent when outputEvent.Is<List<ChatMessage>>():
-                    finalOutput = outputEvent;
-                    break;
-
-                case WorkflowErrorEvent workflowError:
-                    Console.ForegroundColor = ConsoleColor.Red;
-                    Console.Error.WriteLine(workflowError.Exception?.ToString() ?? "Unknown workflow error occurred.");
-                    Console.ResetColor();
-                    break;
-
-                case ExecutorFailedEvent executorFailed:
-                    Console.ForegroundColor = ConsoleColor.Red;
-                    Console.Error.WriteLine($"Executor '{executorFailed.ExecutorId}' failed with {(executorFailed.Data is null ? "unknown error" : $"exception {executorFailed.Data}")}.");
-                    Console.ResetColor();
-                    break;
-            }
-        }
-
-        if (finalOutput?.As<List<ChatMessage>>() is { } transcript)
-        {
-            Console.WriteLine();
-            Console.WriteLine(new string('=', 80));
-            Console.WriteLine();
-            Console.WriteLine("Final Conversation Transcript:");
-            Console.WriteLine();
-
-            foreach (ChatMessage message in transcript)
-            {
-                Console.WriteLine($"{message.AuthorName ?? message.Role.ToString()}: {message.Text}");
-                Console.WriteLine();
-            }
-        }
-    }
-
-    private static void WriteStreamingUpdate(AgentResponseUpdateEvent updateEvent, ref string? lastResponseId)
-    {
-        string responseId = updateEvent.Update.ResponseId ?? updateEvent.Update.MessageId ?? updateEvent.ExecutorId;
-        if (!string.Equals(responseId, lastResponseId, StringComparison.Ordinal))
-        {
-            if (lastResponseId is not null)
-            {
-                Console.WriteLine();
-                Console.WriteLine();
-            }
-
-            Console.Write($"- {updateEvent.ExecutorId}: ");
-            lastResponseId = responseId;
-        }
-
-        if (!string.IsNullOrEmpty(updateEvent.Update.Text))
-        {
-            Console.Write(updateEvent.Update.Text);
-        }
-    }
-
-    private static void WriteMagenticMessage(string title, string? content)
-    {
-        Console.WriteLine();
-        Console.WriteLine($"[Magentic {title}]");
-        Console.WriteLine(content);
-    }
-
-    private static string FormatProgressLedger(MagenticProgressLedger ledger) =>
-        string.Join(Environment.NewLine,
-            $"Request satisfied: {ledger.IsRequestSatisfied}",
-            $"In loop: {ledger.IsInLoop}",
-            $"Making progress: {ledger.IsProgressBeingMade}",
-            $"Next speaker: {ledger.NextSpeaker}",
-            $"Instruction: {ledger.InstructionOrQuestion}");
-
-    private static void PauseIfInteractive()
-    {
-        if (Console.IsInputRedirected || Console.IsOutputRedirected)
-        {
-            return;
-        }
-
-        Console.Write("Press Enter to continue...");
-        Console.ReadLine();
-        Console.WriteLine();
-    }
-}
@@ -1,40 +0,0 @@
-# Magentic Orchestration Sample
-
-This sample showcases the Magentic Orchestration Pattern in .NET, setting up a team with three roles:
-
- **ResearcherAgent** gathers factual background information.
- **CoderAgent** uses `HostedCodeInterpreterTool` for quantitative analysis.
- **MagenticManager** plans the work, tracks progress, and decides who should act next.
-
-## What This Sample Demonstrates
-
- Building a Magentic workflow with `MagenticWorkflowBuilder`
- Combining standard responses-based agents with a code interpreter-enabled participant
- Streaming orchestration events such as the initial plan, replans, and progress-ledger updates
- Printing the final multi-agent conversation transcript
-
-## Prerequisites
-
- `AZURE_AI_PROJECT_ENDPOINT` set to your Azure AI Foundry project endpoint
- `AZURE_AI_MODEL_DEPLOYMENT_NAME` set to your model deployment name (defaults to `gpt-5.4-mini`)
- `az login` completed before running the sample
-
-## Running the Sample
-
-```bash
-dotnet run
-```
-
-## Expected Output
-
-The sample prints:
-
-1. The original task prompt
-2. Streamed updates from the participating agents
-3. Magentic plan and progress-ledger events as the workflow coordinates the team
-4. The final conversation transcript returned by the workflow
-
-## Related Samples
-
- [Handoff Orchestration](../Handoff) - another multi-agent orchestration pattern in .NET workflows
- [Python Magentic workflow sample](../../../../../python/samples/03-workflows/orchestrations/magentic.py) - the source scenario that this sample ports
@@ -62,4 +62,3 @@ Once completed, please proceed to the other samples listed below.
 | Sample | Concepts |
 |--------|----------|
 | [Handoff Orchestration](./Orchestration/Handoff) | Introduces the Handoff Orchestration pattern |
-| [Magentic Orchestration](./Orchestration/Magentic) | Coordinates multiple agents with a Magentic manager, streamed plan events, and a final transcript |
@@ -474,7 +474,6 @@ public sealed class A2AAgent : AIAgent
            ResponseId = statusUpdateEvent.TaskId,
            RawRepresentation = statusUpdateEvent,
            Role = ChatRole.Assistant,
-            MessageId = statusUpdateEvent.Status.Message?.MessageId,
            FinishReason = MapTaskStateToFinishReason(statusUpdateEvent.Status.State),
            AdditionalProperties = statusUpdateEvent.Metadata?.ToAdditionalProperties() ?? [],
            Contents = statusUpdateEvent.Status.GetUserInputRequests(),
@@ -1,6 +1,5 @@
 // Copyright (c) Microsoft. All rights reserved.

-using System;
 using System.ClientModel.Primitives;
 using System.Collections.Generic;
 using System.Reflection;
@@ -10,11 +9,8 @@ using Microsoft.Extensions.AI;
 namespace Microsoft.Agents.AI.Foundry.Hosting;

 /// <summary>
-/// Pipeline policy that emits the hosted-agent <c>User-Agent</c> segment
-/// (<c>"foundry-hosting/agent-framework-dotnet/{version}"</c>), matching Python's hosted
-/// contract (<c>foundry-hosting/agent-framework-python/{version}</c>, see
-/// <c>python/packages/core/agent_framework/_telemetry.py</c>: the hosted prefix is joined
-/// with the base agent-framework segment into a single combined User-Agent value).
+/// 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>
@@ -23,12 +19,6 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// is already present in the <c>User-Agent</c> header, the policy does not append it again.
 /// </para>
 /// <para>
-/// When a bare <c>agent-framework-dotnet/{version}</c> segment is already present (stamped by
-/// the framework-wide <c>AgentFrameworkUserAgentPolicy</c> registered by
-/// <c>FoundryChatClient</c>), this policy <em>replaces</em> that segment with the combined
-/// hosted form so the wire never carries both forms simultaneously, preserving Python parity.
-/// </para>
-/// <para>
 /// This policy is added at hosted-agent resolution time via the MEAI 10.5.1
 /// <see cref="OpenAIRequestPolicies"/> hook on the agent's underlying chat client. It is only
 /// registered when an agent is resolved by the Foundry hosting layer.
@@ -40,12 +30,6 @@ internal sealed class HostedAgentUserAgentPolicy : PipelinePolicy

    private static readonly string s_supplementValue = CreateSupplementValue();

-    /// <summary>Bare segment stamped by <c>AgentFrameworkUserAgentPolicy</c> in the non-hosted scenario; this policy upgrades it in-place when both run.</summary>
-    private const string BareAgentFrameworkPrefix = "agent-framework-dotnet/";
-
-    /// <summary>Combined hosted segment that this policy emits. Recognized in-place so callers whose pipelines already carry a (possibly different-version) combined segment get it replaced rather than double-prefixed (Q-D fix).</summary>
-    private const string CombinedHostedPrefix = "foundry-hosting/agent-framework-dotnet/";
-
    public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
    {
        AppendHeader(message);
@@ -62,52 +46,13 @@ internal sealed class HostedAgentUserAgentPolicy : PipelinePolicy
    {
        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))
+            // Guard against double-append on retries or when the policy
+            // is registered on multiple pipeline positions.
+            if (existing.Contains(s_supplementValue))
            {
                return;
            }

-            // Combined-form check first: if the caller's pipeline already has
-            // `foundry-hosting/agent-framework-dotnet/{version}` (with a version that differs
-            // from ours — otherwise the .Contains above would have returned early), replace the
-            // entire combined span in place. Without this, the bare-prefix search below would
-            // match `agent-framework-dotnet/` *inside* the combined segment and produce a
-            // malformed `foundry-hosting/foundry-hosting/agent-framework-dotnet/...` value.
-            var combinedIdx = existing.IndexOf(CombinedHostedPrefix, StringComparison.Ordinal);
-            if (combinedIdx >= 0)
-            {
-                var combinedEnd = existing.IndexOf(' ', combinedIdx);
-                if (combinedEnd < 0)
-                {
-                    combinedEnd = existing.Length;
-                }
-
-                var replacedCombined = string.Concat(existing.AsSpan(0, combinedIdx), s_supplementValue.AsSpan(), existing.AsSpan(combinedEnd));
-                message.Request.Headers.Set("User-Agent", replacedCombined);
-                return;
-            }
-
-            // If the bare agent-framework segment is present (stamped by
-            // AgentFrameworkUserAgentPolicy when not hosted), upgrade it in place to the
-            // combined hosted form so the wire never carries both segments simultaneously.
-            // Mirrors Python where get_user_agent() returns a single combined string when the
-            // hosted prefix is registered.
-            var idx = existing.IndexOf(BareAgentFrameworkPrefix, StringComparison.Ordinal);
-            if (idx >= 0)
-            {
-                var end = existing.IndexOf(' ', idx);
-                if (end < 0)
-                {
-                    end = existing.Length;
-                }
-
-                var replaced = string.Concat(existing.AsSpan(0, idx), s_supplementValue.AsSpan(), existing.AsSpan(end));
-                message.Request.Headers.Set("User-Agent", replaced);
-                return;
-            }
-
            message.Request.Headers.Set("User-Agent", $"{existing} {s_supplementValue}");
        }
        else
@@ -1,88 +0,0 @@
-// 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;
-
-/// <summary>
-/// Framework-wide pipeline policy that appends the <c>agent-framework-dotnet/{version}</c>
-/// segment to outgoing <c>User-Agent</c> headers, mirroring the
-/// <c>agent-framework-python/{version}</c> contract used by every Python provider package.
-/// </summary>
-/// <remarks>
-/// <para>
-/// The segment value is computed once from the <c>Microsoft.Agents.AI.Foundry</c> assembly's
-/// <see cref="AssemblyInformationalVersionAttribute"/>. 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>
-/// The policy is registered by <c>FoundryChatClient</c> on the underlying chat client's
-/// <c>OpenAIRequestPolicies</c> hook so every outbound Foundry call carries the segment. The
-/// policy is currently colocated with the Foundry package; it is expected to migrate to a
-/// framework-wide location (such as <c>Microsoft.Agents.AI</c>) once another provider package
-/// adopts the same User-Agent contract.
-/// </para>
-/// </remarks>
-internal sealed class AgentFrameworkUserAgentPolicy : PipelinePolicy
-{
-    /// <summary>Gets the singleton policy instance.</summary>
-    public static AgentFrameworkUserAgentPolicy Instance { get; } = new AgentFrameworkUserAgentPolicy();
-
-    private static readonly string s_segmentValue = CreateSegmentValue();
-
-    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_segmentValue))
-            {
-                return;
-            }
-
-            message.Request.Headers.Set("User-Agent", $"{existing} {s_segmentValue}");
-        }
-        else
-        {
-            message.Request.Headers.Set("User-Agent", s_segmentValue);
-        }
-    }
-
-    private static string CreateSegmentValue()
-    {
-        const string Name = "agent-framework-dotnet";
-
-        if (typeof(AgentFrameworkUserAgentPolicy).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;
-    }
-}
@@ -0,0 +1,165 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+using Azure.AI.Extensions.OpenAI;
+using Azure.AI.Projects;
+using Azure.AI.Projects.Agents;
+using Microsoft.Extensions.AI;
+using Microsoft.Shared.DiagnosticIds;
+using Microsoft.Shared.Diagnostics;
+using OpenAI.Responses;
+
+namespace Microsoft.Agents.AI.Foundry;
+
+/// <summary>
+/// Provides a chat client implementation that integrates with Azure AI Agents, enabling chat interactions using
+/// Azure-specific agent capabilities.
+/// </summary>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
+internal sealed class AzureAIProjectChatClient : DelegatingChatClient
+{
+    private readonly ChatClientMetadata? _metadata;
+    private readonly AIProjectClient _agentClient;
+    private readonly ProjectsAgentVersion? _agentVersion;
+    private readonly ProjectsAgentRecord? _agentRecord;
+    private readonly ChatOptions? _chatOptions;
+    private readonly AgentReference _agentReference;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="AzureAIProjectChatClient"/> class.
+    /// </summary>
+    /// <param name="aiProjectClient">An instance of <see cref="AIProjectClient"/> to interact with Azure AI Agents services.</param>
+    /// <param name="agentReference">An instance of <see cref="AgentReference"/> representing the specific agent to use.</param>
+    /// <param name="defaultModelId">The default model to use for the agent, if applicable.</param>
+    /// <param name="chatOptions">An instance of <see cref="ChatOptions"/> representing the options on how the agent was predefined.</param>
+    /// <remarks>
+    /// The <see cref="IChatClient"/> provided should be decorated with a <see cref="AzureAIProjectChatClient"/> for proper functionality.
+    /// </remarks>
+    internal AzureAIProjectChatClient(AIProjectClient aiProjectClient, AgentReference agentReference, string? defaultModelId, ChatOptions? chatOptions)
+        : base(Throw.IfNull(aiProjectClient)
+            .GetProjectOpenAIClient()
+            .GetProjectResponsesClientForAgent(agentReference)
+            .AsIChatClient())
+    {
+        this._agentClient = aiProjectClient;
+        this._agentReference = Throw.IfNull(agentReference);
+        this._metadata = new ChatClientMetadata("microsoft.foundry", defaultModelId: defaultModelId);
+        this._chatOptions = chatOptions;
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="AzureAIProjectChatClient"/> class.
+    /// </summary>
+    /// <param name="aiProjectClient">An instance of <see cref="AIProjectClient"/> to interact with Azure AI Agents services.</param>
+    /// <param name="agentRecord">An instance of <see cref="ProjectsAgentRecord"/> representing the specific agent to use.</param>
+    /// <param name="chatOptions">An instance of <see cref="ChatOptions"/> representing the options on how the agent was predefined.</param>
+    /// <remarks>
+    /// The <see cref="IChatClient"/> provided should be decorated with a <see cref="AzureAIProjectChatClient"/> for proper functionality.
+    /// </remarks>
+    internal AzureAIProjectChatClient(AIProjectClient aiProjectClient, ProjectsAgentRecord agentRecord, ChatOptions? chatOptions)
+        : this(aiProjectClient, Throw.IfNull(agentRecord).GetLatestVersion(), chatOptions)
+    {
+        this._agentRecord = agentRecord;
+    }
+
+    internal AzureAIProjectChatClient(AIProjectClient aiProjectClient, ProjectsAgentVersion agentVersion, ChatOptions? chatOptions)
+        : this(
+              aiProjectClient,
+              CreateAgentReference(Throw.IfNull(agentVersion)),
+              (agentVersion.Definition as DeclarativeAgentDefinition)?.Model,
+              chatOptions)
+    {
+        this._agentVersion = agentVersion;
+    }
+
+    /// <summary>
+    /// Creates an <see cref="AgentReference"/> from an <see cref="ProjectsAgentVersion"/>.
+    /// Uses the agent version's version if available, otherwise defaults to "latest".
+    /// </summary>
+    /// <param name="agentVersion">The agent version to create a reference from.</param>
+    /// <returns>An <see cref="AgentReference"/> for the specified agent version.</returns>
+    private static AgentReference CreateAgentReference(ProjectsAgentVersion agentVersion)
+    {
+        // If the version is null, empty, or whitespace, use "latest" as the default.
+        // This handles cases where hosted agents (like MCP agents) may not have a version assigned.
+        var version = string.IsNullOrWhiteSpace(agentVersion.Version) ? "latest" : agentVersion.Version;
+        return new AgentReference(agentVersion.Name, version);
+    }
+
+    /// <inheritdoc/>
+    public override object? GetService(Type serviceType, object? serviceKey = null)
+    {
+        return (serviceKey is null && serviceType == typeof(ChatClientMetadata))
+            ? this._metadata
+            : (serviceKey is null && serviceType == typeof(AIProjectClient))
+            ? this._agentClient
+            : (serviceKey is null && serviceType == typeof(ProjectsAgentVersion))
+            ? this._agentVersion
+            : (serviceKey is null && serviceType == typeof(ProjectsAgentRecord))
+            ? this._agentRecord
+            : (serviceKey is null && serviceType == typeof(AgentReference))
+            ? this._agentReference
+            : base.GetService(serviceType, serviceKey);
+    }
+
+    /// <inheritdoc/>
+    public override async Task<ChatResponse> GetResponseAsync(IEnumerable<ChatMessage> messages, ChatOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var agentOptions = this.GetAgentEnabledChatOptions(options);
+
+        return await base.GetResponseAsync(messages, agentOptions, cancellationToken).ConfigureAwait(false);
+    }
+
+    /// <inheritdoc/>
+    public override async IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(IEnumerable<ChatMessage> messages, ChatOptions? options = null, [EnumeratorCancellation] CancellationToken cancellationToken = default)
+    {
+        var agentOptions = this.GetAgentEnabledChatOptions(options);
+
+        await foreach (var chunk in base.GetStreamingResponseAsync(messages, agentOptions, cancellationToken).ConfigureAwait(false))
+        {
+            yield return chunk;
+        }
+    }
+
+    private ChatOptions GetAgentEnabledChatOptions(ChatOptions? options)
+    {
+        // Start with a clone of the base chat options defined for the agent, if any.
+        ChatOptions agentEnabledChatOptions = this._chatOptions?.Clone() ?? new();
+
+        // Ignore per-request all options that can't be overridden.
+        agentEnabledChatOptions.Instructions = null;
+        agentEnabledChatOptions.Tools = null;
+        agentEnabledChatOptions.Temperature = null;
+        agentEnabledChatOptions.TopP = null;
+        agentEnabledChatOptions.PresencePenalty = null;
+        agentEnabledChatOptions.ResponseFormat = null;
+
+        // Use the conversation from the request, or the one defined at the client level.
+        agentEnabledChatOptions.ConversationId = options?.ConversationId ?? this._chatOptions?.ConversationId;
+
+        // Preserve the original RawRepresentationFactory
+        var originalFactory = options?.RawRepresentationFactory;
+
+        agentEnabledChatOptions.RawRepresentationFactory = (client) =>
+        {
+            if (originalFactory?.Invoke(this) is not CreateResponseOptions responseCreationOptions)
+            {
+                responseCreationOptions = new CreateResponseOptions();
+            }
+
+            responseCreationOptions.Agent = this._agentReference;
+#pragma warning disable SCME0001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
+            responseCreationOptions.Patch.Remove("$.model"u8);
+#pragma warning restore SCME0001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
+
+            return responseCreationOptions;
+        };
+
+        return agentEnabledChatOptions;
+    }
+}
@@ -23,7 +23,7 @@ namespace Azure.AI.Projects;
 /// Provides extension methods for <see cref="AIProjectClient"/>.
 /// </summary>
 [Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
-public static partial class AIProjectClientExtensions
+public static partial class AzureAIProjectChatClientExtensions
 {
    /// <summary>
    /// Uses an existing server side agent, wrapped as a <see cref="ChatClientAgent"/> using the provided <see cref="AIProjectClient"/> and <see cref="AgentReference"/>.
@@ -63,7 +63,7 @@ public static partial class AIProjectClientExtensions
            clientFactory,
            services);

-        return new FoundryAgent(innerAgent);
+        return new FoundryAgent(aiProjectClient, innerAgent);
    }

    /// <summary>
@@ -132,7 +132,7 @@ public static partial class AIProjectClientExtensions
            !allowDeclarativeMode,
            services);

-        return new FoundryAgent(innerAgent);
+        return new FoundryAgent(aiProjectClient, innerAgent);
    }

    /// <summary>
@@ -165,7 +165,7 @@ public static partial class AIProjectClientExtensions
            !allowDeclarativeMode,
            services);

-        return new FoundryAgent(innerAgent);
+        return new FoundryAgent(aiProjectClient, innerAgent);
    }

    /// <summary>
@@ -246,7 +246,7 @@ public static partial class AIProjectClientExtensions
        Func<IChatClient, IChatClient>? clientFactory,
        IServiceProvider? services)
    {
-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentVersion, agentOptions.ChatOptions);
+        IChatClient chatClient = new AzureAIProjectChatClient(aiProjectClient, agentVersion, agentOptions.ChatOptions);

        if (clientFactory is not null)
        {
@@ -268,7 +268,10 @@ public static partial class AIProjectClientExtensions
        Throw.IfNull(agentOptions.ChatOptions);
        Throw.IfNullOrWhitespace(agentOptions.ChatOptions.ModelId);

-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentOptions.ChatOptions.ModelId);
+        IChatClient chatClient = aiProjectClient
+            .GetProjectOpenAIClient()
+            .GetResponsesClient()
+            .AsIChatClient(agentOptions.ChatOptions.ModelId);

        if (clientFactory is not null)
        {
@@ -295,7 +298,7 @@ public static partial class AIProjectClientExtensions
        Func<IChatClient, IChatClient>? clientFactory,
        IServiceProvider? services)
    {
-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentRecord, agentOptions.ChatOptions);
+        IChatClient chatClient = new AzureAIProjectChatClient(aiProjectClient, agentRecord, agentOptions.ChatOptions);

        if (clientFactory is not null)
        {
@@ -313,7 +316,7 @@ public static partial class AIProjectClientExtensions
        Func<IChatClient, IChatClient>? clientFactory,
        IServiceProvider? services)
    {
-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentReference, defaultModelId: null, agentOptions.ChatOptions);
+        IChatClient chatClient = new AzureAIProjectChatClient(aiProjectClient, agentReference, defaultModelId: null, agentOptions.ChatOptions);

        if (clientFactory is not null)
        {
@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using Azure.AI.Projects;
+using Microsoft.Extensions.AI;
+using Microsoft.Shared.Diagnostics;
+
+namespace Microsoft.Agents.AI.Foundry;
+
+#pragma warning disable OPENAI001
+internal sealed class AzureAIProjectResponsesChatClient : DelegatingChatClient
+{
+    private readonly ChatClientMetadata _metadata;
+    private readonly AIProjectClient _aiProjectClient;
+
+    internal AzureAIProjectResponsesChatClient(AIProjectClient aiProjectClient, string defaultModelId)
+        : base(Throw.IfNull(aiProjectClient)
+            .GetProjectOpenAIClient()
+            .GetProjectResponsesClientForModel(Throw.IfNullOrWhitespace(defaultModelId))
+            .AsIChatClient())
+    {
+        this._aiProjectClient = aiProjectClient;
+        this._metadata = new ChatClientMetadata("microsoft.foundry", defaultModelId: defaultModelId);
+    }
+
+    public override object? GetService(Type serviceType, object? serviceKey = null)
+    {
+        return (serviceKey is null && serviceType == typeof(ChatClientMetadata))
+            ? this._metadata
+            : (serviceKey is null && serviceType == typeof(AIProjectClient))
+            ? this._aiProjectClient
+            : base.GetService(serviceType, serviceKey);
+    }
+}
+#pragma warning restore OPENAI001
@@ -1,42 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Diagnostics.CodeAnalysis;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.DiagnosticIds;
-using Microsoft.Shared.Diagnostics;
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// Foundry-specific extensions on <see cref="ChatClientAgent"/>. Mirrors Python's free
-/// <c>to_prompt_agent(agent)</c> function for agents whose underlying chat client is a
-/// <see cref="FoundryChatClient"/>.
-/// </summary>
-[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
-public static class ChatClientAgentFoundryExtensions
-{
-    /// <summary>
-    /// Converts the supplied agent into a <see cref="ProjectsAgentDefinition"/> ready to publish
-    /// via <c>AgentAdministrationClient.CreateAgentVersionAsync</c>.
-    /// </summary>
-    /// <remarks>
-    /// Only works on agents whose chat client is a <see cref="FoundryChatClient"/> and whose
-    /// construction mode is convertible. The Agent Endpoint construction mode (Mode 3) is not
-    /// convertible because no local definition exists; conversion in that case throws.
-    /// </remarks>
-    /// <param name="agent">The chat client agent to convert.</param>
-    /// <param name="cancellationToken">A token that can cancel an internal server-side fetch when the agent was constructed from a bare <see cref="AgentReference"/>.</param>
-    /// <returns>A <see cref="ProjectsAgentDefinition"/> suitable for publishing.</returns>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent's chat client is not a <see cref="FoundryChatClient"/>; the agent was constructed via the Agent Endpoint mode (Mode 3); no model id is set on the agent's <see cref="ChatOptions"/> for the Responses Agent mode (Mode 1); or the agent contains an <see cref="AITool"/> that cannot be converted to a <c>ResponseTool</c>.</exception>
-    public static Task<ProjectsAgentDefinition> ToPromptAgentAsync(this ChatClientAgent agent, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNull(agent);
-        return FoundryPromptAgentConverter.ConvertAsync(agent.ChatClient, agent.GetService<ChatOptions>(), cancellationToken);
-    }
-}
@@ -39,6 +39,11 @@ namespace Microsoft.Agents.AI.Foundry;
 [Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public sealed class FoundryAgent : DelegatingAIAgent
 {
+    /// <summary>
+    /// The cached <see cref="AIProjectClient"/> supplied to or constructed by the active constructor.
+    /// </summary>
+    private readonly AIProjectClient _aiProjectClient;
+
    /// <summary>
    /// Initializes a new instance of the <see cref="FoundryAgent"/> class using the direct Responses API path.
    /// </summary>
@@ -68,8 +73,9 @@ public sealed class FoundryAgent : DelegatingAIAgent
        : base(CreateInnerAgent(
            CreateProjectClient(projectEndpoint, credential, clientOptions),
            model, instructions, name, description, tools, clientFactory, loggerFactory, services,
-            out _))
+            out var aiProjectClient))
    {
+        this._aiProjectClient = aiProjectClient;
    }

    /// <summary>
@@ -81,11 +87,9 @@ public sealed class FoundryAgent : DelegatingAIAgent
    /// </param>
    /// <param name="credential">The authentication credential.</param>
    /// <param name="clientOptions">
-    /// Optional configuration for the underlying <see cref="ProjectOpenAIClient"/>. When supplied:
+    /// Optional configuration for the underlying <see cref="ProjectResponsesClient"/>. When supplied:
    /// <list type="bullet">
    ///   <item><description>The instance is passed through to the per-agent client; pipeline policies added via <c>AddPolicy(...)</c> on it execute on the per-agent traffic.</description></item>
-    ///   <item><description><c>Endpoint</c> and <see cref="ProjectOpenAIClientOptions.AgentName"/> are owned by this constructor and are overwritten with values derived from <paramref name="agentEndpoint"/>; any caller value is replaced.</description></item>
-    ///   <item><description>For the project-level conversations client a separate fresh options bag is built that copies only <see cref="ClientPipelineOptions.RetryPolicy"/>, <see cref="ClientPipelineOptions.NetworkTimeout"/>, <see cref="ClientPipelineOptions.Transport"/>, and <c>UserAgentApplicationId</c>; pipeline policies added via <c>AddPolicy(...)</c> do <strong>not</strong> propagate to the conversations pipeline.</description></item>
    /// </list>
    /// </param>
    /// <param name="tools">Optional tools to use when interacting with the agent.</param>
@@ -109,37 +113,43 @@ public sealed class FoundryAgent : DelegatingAIAgent
        IList<AITool>? tools = null,
        Func<IChatClient, IChatClient>? clientFactory = null,
        IServiceProvider? services = null)
-        : base(CreateInnerAgentFromAgentEndpoint(agentEndpoint, credential, clientOptions, tools, clientFactory, services))
+        : base(CreateInnerAgentFromAgentEndpoint(agentEndpoint, credential, clientOptions, tools, clientFactory, services, out var aiProjectClient))
    {
+        this._aiProjectClient = aiProjectClient;
    }

    /// <summary>
-    /// Internal constructor used by the <c>AsAIAgent(this AIProjectClient, Uri, ...)</c>
-    /// extension where the caller already has an <see cref="AIProjectClient"/> and the agent
-    /// endpoint URI. Reuses the supplied client's pipeline (no new credential or transport is
-    /// stamped) and surfaces the agent through a <see cref="FoundryChatClient"/> just like the
-    /// public agent-endpoint ctor.
+    /// Initializes a new instance of the <see cref="FoundryAgent"/> class from an agent-specific
+    /// endpoint while reusing an existing <see cref="AIProjectClient"/>.
    /// </summary>
+    /// <param name="aiProjectClient">An existing <see cref="AIProjectClient"/> rooted at the same project as <paramref name="agentEndpoint"/>.</param>
+    /// <param name="agentEndpoint">
+    /// The agent-specific endpoint URI. Must be of the shape
+    /// <c>https://&lt;host&gt;/.../projects/&lt;project&gt;/agents/&lt;agentName&gt;/endpoint/protocols/openai</c>.
+    /// </param>
+    /// <param name="tools">Optional tools to use when interacting with the agent.</param>
+    /// <param name="clientFactory">Provides a way to customize the creation of the underlying <see cref="IChatClient"/>.</param>
+    /// <param name="services">Optional service provider for resolving dependencies required by AI functions.</param>
+    /// <exception cref="ArgumentNullException"><paramref name="aiProjectClient"/> or <paramref name="agentEndpoint"/> is null.</exception>
+    /// <exception cref="ArgumentException"><paramref name="agentEndpoint"/> does not match the expected agent-endpoint shape.</exception>
    internal FoundryAgent(
        AIProjectClient aiProjectClient,
        Uri agentEndpoint,
        IList<AITool>? tools = null,
        Func<IChatClient, IChatClient>? clientFactory = null,
        IServiceProvider? services = null)
-        : base(CreateInnerAgentFromAgentEndpointReusingProjectClient(aiProjectClient, agentEndpoint, tools, clientFactory, services))
+        : base(BuildAgentEndpointInnerAgent(aiProjectClient, agentEndpoint, clientOptions: null, tools, clientFactory, services))
    {
+        this._aiProjectClient = Throw.IfNull(aiProjectClient);
    }

    /// <summary>
-    /// Internal constructor used by <c>AsAIAgent</c> extension methods that already have a
-    /// configured <see cref="ChatClientAgent"/>. The inner agent already routes through a
-    /// <see cref="FoundryChatClient"/> whose <c>GetService&lt;AIProjectClient&gt;()</c> surfaces
-    /// the project client to downstream callers, so the agent does not also need a private
-    /// <see cref="AIProjectClient"/> reference here.
+    /// Internal constructor used by <c>AsAIAgent</c> extension methods that already have an <see cref="AIProjectClient"/> and a configured <see cref="ChatClientAgent"/>.
    /// </summary>
-    internal FoundryAgent(ChatClientAgent innerAgent)
+    internal FoundryAgent(AIProjectClient aiProjectClient, ChatClientAgent innerAgent)
        : base(WireClientHeaders(Throw.IfNull(innerAgent)))
    {
+        this._aiProjectClient = Throw.IfNull(aiProjectClient);
    }

    #region Convenience methods
@@ -172,13 +182,7 @@ public sealed class FoundryAgent : DelegatingAIAgent
    /// <returns>A <see cref="ChatClientAgentSession"/> linked to the newly created server-side conversation.</returns>
    public async Task<ChatClientAgentSession> CreateConversationSessionAsync(CancellationToken cancellationToken = default)
    {
-        // The inner FoundryChatClient surfaces an AIProjectClient via GetService for all
-        // three construction modes (Plan #2 Agent Endpoint mode materialization). Resolve it through the
-        // delegating chain at call time instead of caching a private reference on this agent.
-        var aiProjectClient = this.GetService<AIProjectClient>()
-            ?? throw new InvalidOperationException(
-                "FoundryAgent inner chain does not expose an AIProjectClient; cannot create a project-level conversation session.");
-        var conversationsClient = aiProjectClient.GetProjectOpenAIClient().GetProjectConversationsClient();
+        var conversationsClient = this._aiProjectClient.ProjectOpenAIClient.GetProjectConversationsClient();

        var conversation = (await conversationsClient.CreateProjectConversationAsync(options: null, cancellationToken).ConfigureAwait(false)).Value;

@@ -192,6 +196,17 @@ public sealed class FoundryAgent : DelegatingAIAgent

    #endregion

+    /// <inheritdoc/>
+    public override object? GetService(Type serviceType, object? serviceKey = null)
+    {
+        if (serviceKey is null && serviceType == typeof(AIProjectClient))
+        {
+            return this._aiProjectClient;
+        }
+
+        return base.GetService(serviceType, serviceKey);
+    }
+
    #region Private helpers

    private static AIAgent CreateInnerAgent(
@@ -236,7 +251,7 @@ public sealed class FoundryAgent : DelegatingAIAgent
        Throw.IfNull(agentOptions.ChatOptions);
        Throw.IfNullOrWhitespace(agentOptions.ChatOptions.ModelId);

-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentOptions.ChatOptions.ModelId);
+        IChatClient chatClient = new AzureAIProjectResponsesChatClient(aiProjectClient, agentOptions.ChatOptions.ModelId);

        if (clientFactory is not null)
        {
@@ -273,10 +288,16 @@ public sealed class FoundryAgent : DelegatingAIAgent
    }

    /// <summary>
-    /// Builds the inner <see cref="ChatClientAgent"/> for the agent-endpoint constructor. The
-    /// per-agent <see cref="ProjectOpenAIClient"/> shape and URL parsing are owned by
-    /// <see cref="FoundryChatClient"/>; we just construct it in the Agent Endpoint mode (Mode 3)
-    /// and pass the inner chat client through any caller-provided <paramref name="clientFactory"/>.
+    /// Builds the inner <see cref="ChatClientAgent"/> for the agent-endpoint constructor by
+    /// constructing a project-scoped <see cref="ProjectOpenAIClient"/> and using
+    /// <see cref="ProjectOpenAIClient.GetProjectResponsesClientForAgentEndpoint(string, string?, ProjectOpenAIClientOptions?)"/>.
+    /// This routes the outbound URL through the per-agent endpoint shape that the Foundry service
+    /// expects for hosted agents and lets the SDK auto-append the <c>api-version</c> query string.
+    /// Caller-supplied <paramref name="clientOptions"/> are passed through to the per-agent
+    /// client with <c>Endpoint</c> and
+    /// <see cref="ProjectOpenAIClientOptions.AgentName"/> overridden by values derived from
+    /// <paramref name="agentEndpoint"/>; any policies the caller added via <c>AddPolicy</c>
+    /// remain in effect on the per-agent pipeline. The MEAI user-agent policy is appended last.
    /// </summary>
    private static AIAgent CreateInnerAgentFromAgentEndpoint(
        Uri agentEndpoint,
@@ -284,37 +305,29 @@ public sealed class FoundryAgent : DelegatingAIAgent
        ProjectOpenAIClientOptions? clientOptions,
        IList<AITool>? tools,
        Func<IChatClient, IChatClient>? clientFactory,
-        IServiceProvider? services)
+        IServiceProvider? services,
+        out AIProjectClient outClient)
    {
        Throw.IfNull(agentEndpoint);
        Throw.IfNull(credential);

-        IChatClient chatClient = new FoundryChatClient(agentEndpoint, credential, clientOptions);
-        var agentName = ((FoundryChatClient)chatClient).AgentName!;
+        var (_, projectRoot) = ParseAgentEndpoint(agentEndpoint);
+        outClient = CreateProjectClient(projectRoot, credential, CreateProjectClientOptions(clientOptions));

-        if (clientFactory is not null)
-        {
-            chatClient = clientFactory(chatClient);
-        }
-
-        ChatClientAgentOptions agentOptions = new()
-        {
-            Id = agentName,
-            Name = agentName,
-            ChatOptions = new() { Tools = tools },
-        };
-
-        return WireClientHeaders(new ChatClientAgent(chatClient, agentOptions, services: services));
+        return BuildAgentEndpointInnerAgent(outClient, agentEndpoint, clientOptions, tools, clientFactory, services);
    }

    /// <summary>
-    /// Variant of <see cref="CreateInnerAgentFromAgentEndpoint"/> that reuses an existing
-    /// <see cref="AIProjectClient"/>'s pipeline instead of stamping a fresh credential. Used by
-    /// the <c>AsAIAgent(AIProjectClient, Uri agentEndpoint, ...)</c> extension overload.
+    /// Builds the inner <see cref="ChatClientAgent"/> for an agent endpoint against a pre-built
+    /// <see cref="AIProjectClient"/>. The caller is responsible for ensuring the supplied client
+    /// is rooted at the same project as <paramref name="agentEndpoint"/>; the agent name is
+    /// parsed from the endpoint URI and passed to
+    /// <see cref="ProjectOpenAIClient.GetProjectResponsesClientForAgentEndpoint(string, string?, ProjectOpenAIClientOptions?)"/>.
    /// </summary>
-    private static AIAgent CreateInnerAgentFromAgentEndpointReusingProjectClient(
+    private static AIAgent BuildAgentEndpointInnerAgent(
        AIProjectClient aiProjectClient,
        Uri agentEndpoint,
+        ProjectOpenAIClientOptions? clientOptions,
        IList<AITool>? tools,
        Func<IChatClient, IChatClient>? clientFactory,
        IServiceProvider? services)
@@ -322,9 +335,14 @@ public sealed class FoundryAgent : DelegatingAIAgent
        Throw.IfNull(aiProjectClient);
        Throw.IfNull(agentEndpoint);

-        IChatClient chatClient = new FoundryChatClient(aiProjectClient, agentEndpoint, clientOptions: null);
-        var agentName = ((FoundryChatClient)chatClient).AgentName!;
+        var (agentName, _) = ParseAgentEndpoint(agentEndpoint);

+        var perAgentOptions = clientOptions ?? new ProjectOpenAIClientOptions();
+        perAgentOptions.AddPolicy(RequestOptionsExtensions.UserAgentPolicy, PipelinePosition.PerCall);
+
+        IChatClient chatClient = aiProjectClient.ProjectOpenAIClient
+            .GetProjectResponsesClientForAgentEndpoint(agentName, options: perAgentOptions)
+            .AsIChatClient();
        if (clientFactory is not null)
        {
            chatClient = clientFactory(chatClient);
@@ -340,13 +358,6 @@ public sealed class FoundryAgent : DelegatingAIAgent
        return WireClientHeaders(new ChatClientAgent(chatClient, agentOptions, services: services));
    }

-    /// <summary>
-    /// Parses an agent endpoint URI. Delegates to <see cref="FoundryChatClient.ParseAgentEndpoint(Uri)"/>
-    /// so the chat client and the agent share a single source of truth for the URL shape.
-    /// </summary>
-    internal static (string AgentName, Uri ProjectRoot) ParseAgentEndpoint(Uri agentEndpoint)
-        => FoundryChatClient.ParseAgentEndpoint(agentEndpoint);
-
    /// <summary>
    /// Parses an agent endpoint URI of shape
    /// <c>https://&lt;host&gt;/.../projects/&lt;project&gt;/agents/&lt;agentName&gt;/endpoint/protocols/openai</c>
@@ -358,12 +369,90 @@ public sealed class FoundryAgent : DelegatingAIAgent
    /// strips query string and fragment. Throws <see cref="ArgumentException"/> for inputs that
    /// do not match the expected shape.
    /// </remarks>
+    /// <exception cref="ArgumentException">
+    /// The endpoint is missing the <c>/agents/</c> segment, has an empty agent name, or has a
+    /// suffix other than <c>/endpoint/protocols/openai</c>.
+    /// </exception>
+    internal static (string AgentName, Uri ProjectRoot) ParseAgentEndpoint(Uri agentEndpoint)
+    {
+        Throw.IfNull(agentEndpoint);
+
+        const string AgentsSegment = "/agents/";
+        const string ExpectedSuffix = "/endpoint/protocols/openai";
+
+        var path = agentEndpoint.AbsolutePath.TrimEnd('/');
+        var idx = path.IndexOf(AgentsSegment, StringComparison.OrdinalIgnoreCase);
+        if (idx < 0)
+        {
+            throw new ArgumentException(
+                $"Expected an agent endpoint of shape 'https://<host>/.../projects/<project>/agents/<agentName>/endpoint/protocols/openai' but got '{agentEndpoint}'.",
+                nameof(agentEndpoint));
+        }
+
+        var afterAgents = path.Substring(idx + AgentsSegment.Length);
+        var nextSlash = afterAgents.IndexOf('/');
+        if (nextSlash <= 0)
+        {
+            throw new ArgumentException(
+                $"Agent endpoint '{agentEndpoint}' is missing the '<agentName>{ExpectedSuffix}' suffix.",
+                nameof(agentEndpoint));
+        }
+
+        var agentName = afterAgents.Substring(0, nextSlash);
+        var suffix = afterAgents.Substring(nextSlash);
+        if (!string.Equals(suffix, ExpectedSuffix, StringComparison.OrdinalIgnoreCase))
+        {
+            throw new ArgumentException(
+                $"Agent endpoint '{agentEndpoint}' has an unexpected suffix '{suffix}'. Expected '{ExpectedSuffix}'.",
+                nameof(agentEndpoint));
+        }
+
+        var rootPath = path.Substring(0, idx);
+        var projectRoot = new UriBuilder(agentEndpoint)
+        {
+            Path = rootPath,
+            Query = string.Empty,
+            Fragment = string.Empty,
+        }.Uri;
+
+        return (agentName, projectRoot);
+    }
+
    private static AIProjectClient CreateProjectClient(Uri endpoint, AuthenticationTokenProvider credential, AIProjectClientOptions? clientOptions = null)
    {
        Throw.IfNull(endpoint);
        Throw.IfNull(credential);

-        return new AIProjectClient(endpoint, credential, clientOptions ?? new AIProjectClientOptions());
+        clientOptions ??= new AIProjectClientOptions();
+        clientOptions.AddPolicy(RequestOptionsExtensions.UserAgentPolicy, PipelinePosition.PerCall);
+        return new AIProjectClient(endpoint, credential, clientOptions);
+    }
+
+    internal static AIProjectClientOptions? CreateProjectClientOptions(ProjectOpenAIClientOptions? clientOptions)
+    {
+        if (clientOptions is null)
+        {
+            return null;
+        }
+
+        // Copy pipeline behavior the caller configured on the per-agent options bag onto the
+        // project-level options bag so the agent endpoint client honors it. UserAgentApplicationId
+        // is project-level (not derived from the agent endpoint), so it must be carried through too.
+        var projectOptions = new AIProjectClientOptions
+        {
+            Transport = clientOptions.Transport,
+            RetryPolicy = clientOptions.RetryPolicy,
+            NetworkTimeout = clientOptions.NetworkTimeout,
+            MessageLoggingPolicy = clientOptions.MessageLoggingPolicy,
+            UserAgentApplicationId = clientOptions.UserAgentApplicationId,
+        };
+
+        if (clientOptions.ClientLoggingOptions is not null)
+        {
+            projectOptions.ClientLoggingOptions = clientOptions.ClientLoggingOptions;
+        }
+
+        return projectOptions;
    }

    #endregion
@@ -1,116 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Collections.Generic;
-using System.Diagnostics.CodeAnalysis;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.DiagnosticIds;
-using Microsoft.Shared.Diagnostics;
-using OpenAI.Files;
-using OpenAI.VectorStores;
-
-#pragma warning disable OPENAI001
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// Foundry-specific extensions on <see cref="FoundryAgent"/>. Hosts the prompt-agent converter
-/// plus thin forwarders that surface the file and vector-store helpers from the inner
-/// <see cref="FoundryChatClient"/> at the agent level so callers do not need to drop down to
-/// <c>agent.GetService&lt;FoundryChatClient&gt;().X()</c> for common workflows.
-/// </summary>
-[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
-public static class FoundryAgentExtensions
-{
-    /// <summary>
-    /// Converts the supplied <see cref="FoundryAgent"/> into a <see cref="ProjectsAgentDefinition"/>
-    /// ready to publish via <c>AgentAdministrationClient.CreateAgentVersionAsync</c>.
-    /// </summary>
-    /// <remarks>
-    /// The Agent Endpoint construction mode (Mode 3) is not convertible because no local
-    /// definition exists; conversion in that case throws <see cref="InvalidOperationException"/>.
-    /// </remarks>
-    /// <param name="agent">The Foundry agent to convert.</param>
-    /// <param name="cancellationToken">A token that can cancel an internal server-side fetch when the agent was constructed from a bare <see cref="AgentReference"/>.</param>
-    /// <returns>A <see cref="ProjectsAgentDefinition"/> suitable for publishing.</returns>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent's chat client is not a <see cref="FoundryChatClient"/>; the agent was constructed via the Agent Endpoint mode (Mode 3); no model id is set on the agent's <see cref="ChatOptions"/> for the Responses Agent mode (Mode 1); or the agent contains an <see cref="AITool"/> that cannot be converted to a <c>ResponseTool</c>.</exception>
-    public static Task<ProjectsAgentDefinition> ToPromptAgentAsync(this FoundryAgent agent, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNull(agent);
-
-        var innerChatClient = agent.GetService<IChatClient>()
-            ?? throw new InvalidOperationException(
-                "ToPromptAgentAsync could not resolve the inner IChatClient on the FoundryAgent.");
-        var chatOptions = agent.GetService<ChatOptions>();
-        return FoundryPromptAgentConverter.ConvertAsync(innerChatClient, chatOptions, cancellationToken);
-    }
-
-    /// <summary>
-    /// Uploads a file to the project. Thin forwarder to
-    /// <see cref="FoundryChatClient.UploadFileAsync(string, FileUploadPurpose, CancellationToken)"/>
-    /// on the agent's inner <see cref="FoundryChatClient"/>.
-    /// </summary>
-    /// <param name="agent">The Foundry agent whose inner chat client owns the upload pipeline.</param>
-    /// <param name="filePath">Path to the file to upload.</param>
-    /// <param name="purpose">The upload purpose (e.g. <see cref="FileUploadPurpose.Assistants"/>).</param>
-    /// <param name="cancellationToken">A token that can cancel the upload.</param>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent does not expose a <see cref="FoundryChatClient"/> via <see cref="AIAgent.GetService{TService}(object?)"/>.</exception>
-    public static Task<OpenAIFile> UploadFileAsync(this FoundryAgent agent, string filePath, FileUploadPurpose purpose, CancellationToken cancellationToken = default)
-        => RequireFoundryChatClient(agent).UploadFileAsync(filePath, purpose, cancellationToken);
-
-    /// <summary>
-    /// Deletes a previously uploaded file. Thin forwarder to
-    /// <see cref="FoundryChatClient.DeleteFileAsync(string, CancellationToken)"/>.
-    /// </summary>
-    /// <param name="agent">The Foundry agent whose inner chat client owns the file pipeline.</param>
-    /// <param name="fileId">The file id returned by <see cref="UploadFileAsync(FoundryAgent, string, FileUploadPurpose, CancellationToken)"/>.</param>
-    /// <param name="cancellationToken">A token that can cancel the delete.</param>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent does not expose a <see cref="FoundryChatClient"/>.</exception>
-    public static Task<FileDeletionResult> DeleteFileAsync(this FoundryAgent agent, string fileId, CancellationToken cancellationToken = default)
-        => RequireFoundryChatClient(agent).DeleteFileAsync(fileId, cancellationToken);
-
-    /// <summary>
-    /// Uploads the supplied files, creates a vector store containing them, and waits until the
-    /// store leaves the in-progress state. Thin forwarder to
-    /// <see cref="FoundryChatClient.CreateVectorStoreAsync(string, IEnumerable{string}, TimeSpan?, TimeSpan?, CancellationToken)"/>.
-    /// </summary>
-    /// <param name="agent">The Foundry agent whose inner chat client owns the file and vector-store pipeline.</param>
-    /// <param name="name">The vector store name.</param>
-    /// <param name="filePaths">Paths to files to upload and attach to the store.</param>
-    /// <param name="expiresAfter">Optional last-active-at expiration window.</param>
-    /// <param name="pollingTimeout">Optional upper bound on the wait for the vector store to leave the in-progress state. Defaults to 5 minutes; pass <see cref="Timeout.InfiniteTimeSpan"/> to disable.</param>
-    /// <param name="cancellationToken">A token that can cancel the orchestration.</param>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent does not expose a <see cref="FoundryChatClient"/>.</exception>
-    /// <exception cref="TimeoutException">The vector store did not leave the in-progress state within <paramref name="pollingTimeout"/>.</exception>
-    public static Task<VectorStore> CreateVectorStoreAsync(this FoundryAgent agent, string name, IEnumerable<string> filePaths, TimeSpan? expiresAfter = null, TimeSpan? pollingTimeout = null, CancellationToken cancellationToken = default)
-        => RequireFoundryChatClient(agent).CreateVectorStoreAsync(name, filePaths, expiresAfter, pollingTimeout, cancellationToken);
-
-    /// <summary>
-    /// Deletes a vector store. Thin forwarder to
-    /// <see cref="FoundryChatClient.DeleteVectorStoreAsync(string, CancellationToken)"/>.
-    /// </summary>
-    /// <param name="agent">The Foundry agent whose inner chat client owns the vector-store pipeline.</param>
-    /// <param name="vectorStoreId">The vector store id.</param>
-    /// <param name="cancellationToken">A token that can cancel the delete.</param>
-    /// <exception cref="ArgumentNullException"><paramref name="agent"/> is <see langword="null"/>.</exception>
-    /// <exception cref="InvalidOperationException">The agent does not expose a <see cref="FoundryChatClient"/>.</exception>
-    public static Task<VectorStoreDeletionResult> DeleteVectorStoreAsync(this FoundryAgent agent, string vectorStoreId, CancellationToken cancellationToken = default)
-        => RequireFoundryChatClient(agent).DeleteVectorStoreAsync(vectorStoreId, cancellationToken);
-
-    private static FoundryChatClient RequireFoundryChatClient(FoundryAgent agent)
-    {
-        Throw.IfNull(agent);
-        return agent.GetService<FoundryChatClient>()
-            ?? throw new InvalidOperationException(
-                "FoundryAgent does not expose a FoundryChatClient via GetService<FoundryChatClient>(). " +
-                "File and vector-store helpers require the agent's inner chat client to be a FoundryChatClient.");
-    }
-}
@@ -1,703 +0,0 @@
-// 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.IO;
-using System.Runtime.CompilerServices;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.DiagnosticIds;
-using Microsoft.Shared.Diagnostics;
-using OpenAI.Files;
-using OpenAI.Responses;
-using OpenAI.VectorStores;
-
-#pragma warning disable OPENAI001
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// Foundry chat-client decorator that unifies the three Foundry chat-client construction
-/// modes (Responses Agent, Prompt Agent, Agent Endpoint) behind a single type and centralizes
-/// Foundry-specific concerns: <c>microsoft.foundry</c> telemetry tagging,
-/// <c>agent-framework-dotnet/{version}</c> User-Agent stamping, <c>x-ms-served-model</c>
-/// response-header capture, and (for Prompt Agents) per-request payload mutation that injects
-/// the agent reference and strips per-request overrides that the server owns.
-/// </summary>
-/// <remarks>
-/// <para>
-/// Replaces the previous <c>AzureAIProjectChatClient</c> and <c>AzureAIProjectResponsesChatClient</c>
-/// decorators. All Foundry entry points (the public <c>FoundryAgent</c> constructors and the
-/// <c>AIProjectClientExtensions.AsAIAgent</c> overloads) now construct a
-/// <see cref="FoundryChatClient"/> internally, so telemetry and the agent-framework User-Agent
-/// segment are uniform across paths.
-/// </para>
-/// <para>
-/// The three construction modes are:
-/// </para>
-/// <list type="bullet">
-///   <item><description><b>Responses Agent</b> (Mode 1): direct Responses API call against a project-level model id; no server-side agent definition exists. Constructed from <c>(AIProjectClient, modelId)</c>.</description></item>
-///   <item><description><b>Prompt Agent</b> (Mode 2): server-side agent definition (a <see cref="ProjectsAgentDefinition"/>, typically a <see cref="DeclarativeAgentDefinition"/>) invoked by <see cref="AgentReference"/> against the project Responses URL. Constructed from <see cref="AgentReference"/>, <see cref="ProjectsAgentVersion"/>, or <see cref="ProjectsAgentRecord"/>.</description></item>
-///   <item><description><b>Agent Endpoint</b> (Mode 3): invocation via the per-agent endpoint URL <c>…/projects/{p}/agents/{name}/endpoint/protocols/openai</c>. The agent behind the endpoint can be either a hosted (container-backed) agent or a Prompt Agent. Constructed from <c>(Uri agentEndpoint, credential)</c>.</description></item>
-/// </list>
-/// <para>
-/// Note: "Hosted Agent" refers to a container-based runtime agent (see
-/// <c>Microsoft.Agents.AI.Foundry.Hosting</c>) and is the <i>kind</i> of agent that may sit
-/// behind an Agent Endpoint. It is not synonymous with the Agent Endpoint mode itself.
-/// </para>
-/// </remarks>
-[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
-public sealed class FoundryChatClient : DelegatingChatClient
-{
-    private readonly ChatClientMetadata _metadata;
-    private readonly AIProjectClient? _aiProjectClient;
-    private readonly AgentReference? _agentReference;
-    private readonly ProjectsAgentVersion? _agentVersion;
-    private readonly ProjectsAgentRecord? _agentRecord;
-    private readonly ChatOptions? _baseChatOptions;
-
-    /// <summary>
-    /// Initializes a new instance for the Responses Agent mode (Mode 1): direct Responses API
-    /// call against a project-level model id; no server-side agent definition exists.
-    /// </summary>
-    /// <param name="aiProjectClient">The project client.</param>
-    /// <param name="modelId">The model deployment id.</param>
-    internal FoundryChatClient(AIProjectClient aiProjectClient, string modelId)
-        : base(Throw.IfNull(aiProjectClient)
-            .GetProjectOpenAIClient()
-            .GetProjectResponsesClientForModel(Throw.IfNullOrWhitespace(modelId))
-            .AsIChatClient())
-    {
-        this._aiProjectClient = aiProjectClient;
-        this._metadata = new ChatClientMetadata("microsoft.foundry", defaultModelId: modelId);
-        TryRegisterAgentFrameworkUserAgentPolicy(this.InnerClient);
-        TryRegisterServedModelPolicy(this.InnerClient);
-    }
-
-    /// <summary>
-    /// Initializes a new instance for the Prompt Agent mode (Mode 2): server-side agent
-    /// definition invoked by <see cref="AgentReference"/>.
-    /// </summary>
-    internal FoundryChatClient(AIProjectClient aiProjectClient, AgentReference agentReference, string? defaultModelId, ChatOptions? baseChatOptions)
-        : base(Throw.IfNull(aiProjectClient)
-            .GetProjectOpenAIClient()
-            .GetProjectResponsesClientForAgent(Throw.IfNull(agentReference))
-            .AsIChatClient())
-    {
-        this._aiProjectClient = aiProjectClient;
-        this._agentReference = agentReference;
-        this._metadata = new ChatClientMetadata("microsoft.foundry", defaultModelId: defaultModelId);
-        this._baseChatOptions = baseChatOptions;
-        this.AgentName = agentReference.Name;
-        TryRegisterAgentFrameworkUserAgentPolicy(this.InnerClient);
-        TryRegisterServedModelPolicy(this.InnerClient);
-    }
-
-    /// <summary>
-    /// Initializes a new instance for the Prompt Agent mode (Mode 2, record variant):
-    /// server-side agent definition invoked by record, resolving to the latest version.
-    /// </summary>
-    internal FoundryChatClient(AIProjectClient aiProjectClient, ProjectsAgentRecord agentRecord, ChatOptions? baseChatOptions)
-        : this(aiProjectClient, Throw.IfNull(agentRecord).GetLatestVersion(), baseChatOptions)
-    {
-        this._agentRecord = agentRecord;
-    }
-
-    /// <summary>
-    /// Initializes a new instance for the Prompt Agent mode (Mode 2, version variant):
-    /// server-side agent definition invoked by a specific version.
-    /// </summary>
-    internal FoundryChatClient(AIProjectClient aiProjectClient, ProjectsAgentVersion agentVersion, ChatOptions? baseChatOptions)
-        : this(
-              aiProjectClient,
-              CreateAgentReference(Throw.IfNull(agentVersion)),
-              (agentVersion.Definition as DeclarativeAgentDefinition)?.Model,
-              baseChatOptions)
-    {
-        this._agentVersion = agentVersion;
-    }
-
-    /// <summary>
-    /// Initializes a new instance for the Agent Endpoint mode (Mode 3): invocation via the
-    /// per-agent endpoint URL. Parses the URL into its per-agent
-    /// <see cref="ProjectOpenAIClient"/> shape internally and forwards through the resulting
-    /// responses client.
-    /// </summary>
-    /// <param name="agentEndpoint">
-    /// The agent-specific endpoint URI. Must be of the shape
-    /// <c>https://&lt;host&gt;/.../projects/&lt;project&gt;/agents/&lt;agentName&gt;/endpoint/protocols/openai</c>.
-    /// </param>
-    /// <param name="credential">The authentication credential.</param>
-    /// <param name="clientOptions">Optional per-agent client options. <c>Endpoint</c> and <c>AgentName</c> are owned by this ctor and overridden with values derived from <paramref name="agentEndpoint"/>.</param>
-    internal FoundryChatClient(Uri agentEndpoint, AuthenticationTokenProvider credential, ProjectOpenAIClientOptions? clientOptions)
-        : this(BuildAgentEndpointInner(agentEndpoint, credential, clientOptions))
-    {
-    }
-
-    /// <summary>
-    /// Initializes a new instance for the Agent Endpoint mode (Mode 3) by reusing an existing
-    /// <see cref="AIProjectClient"/>'s pipeline. Equivalent to the
-    /// <see cref="FoundryChatClient(Uri, AuthenticationTokenProvider, ProjectOpenAIClientOptions?)"/>
-    /// constructor but skips building a fresh per-agent pipeline: the project-level
-    /// <see cref="ProjectOpenAIClient"/> on <paramref name="aiProjectClient"/> is used directly.
-    /// </summary>
-    /// <param name="aiProjectClient">The project client already configured at the project root containing <paramref name="agentEndpoint"/>.</param>
-    /// <param name="agentEndpoint">The per-agent endpoint URI. Same shape constraints as the other agent-endpoint ctor.</param>
-    /// <param name="clientOptions">Optional per-agent client options applied to the per-agent <c>GetProjectResponsesClientForAgentEndpoint</c> call.</param>
-    internal FoundryChatClient(AIProjectClient aiProjectClient, Uri agentEndpoint, ProjectOpenAIClientOptions? clientOptions)
-        : this(BuildAgentEndpointInnerFromProjectClient(aiProjectClient, agentEndpoint, clientOptions))
-    {
-    }
-
-    private FoundryChatClient(AgentEndpointInner inner)
-        : base(inner.ChatClient)
-    {
-        this._aiProjectClient = inner.AIProjectClient;
-        this.AgentName = inner.AgentName;
-        this._metadata = new ChatClientMetadata("microsoft.foundry");
-        TryRegisterAgentFrameworkUserAgentPolicy(this.InnerClient);
-        TryRegisterServedModelPolicy(this.InnerClient);
-    }
-
-    /// <summary>
-    /// Gets the agent name associated with this chat client.
-    /// </summary>
-    /// <remarks>
-    /// <para>Set in two cases:</para>
-    /// <list type="bullet">
-    /// <item>
-    /// <description>
-    /// Prompt Agent mode (Mode 2): the value of <see cref="AgentReference.Name"/> supplied at
-    /// construction.
-    /// </description>
-    /// </item>
-    /// <item>
-    /// <description>
-    /// Agent Endpoint mode (Mode 3): the agent name segment parsed from the supplied agent
-    /// endpoint URI.
-    /// </description>
-    /// </item>
-    /// </list>
-    /// <para>
-    /// Returns <see langword="null"/> for the Responses Agent mode (Mode 1) where no agent name
-    /// exists.
-    /// </para>
-    /// </remarks>
-    internal string? AgentName { get; }
-
-    /// <inheritdoc/>
-    public override object? GetService(Type serviceType, object? serviceKey = null)
-    {
-        return (serviceKey is null && serviceType == typeof(ChatClientMetadata))
-            ? this._metadata
-            : (serviceKey is null && serviceType == typeof(AIProjectClient))
-            ? this._aiProjectClient
-            : (serviceKey is null && serviceType == typeof(AgentReference))
-            ? this._agentReference
-            : (serviceKey is null && serviceType == typeof(ProjectsAgentVersion))
-            ? this._agentVersion
-            : (serviceKey is null && serviceType == typeof(ProjectsAgentRecord))
-            ? this._agentRecord
-            : base.GetService(serviceType, serviceKey);
-    }
-
-    /// <inheritdoc/>
-    public override async Task<ChatResponse> GetResponseAsync(IEnumerable<ChatMessage> messages, ChatOptions? options = null, CancellationToken cancellationToken = default)
-    {
-        var effectiveOptions = this._agentReference is not null
-            ? this.GetAgentEnabledChatOptions(options)
-            : options;
-
-        var box = new StrongBox<string?>(null);
-        var previous = ServedModelScope.Current;
-        ServedModelScope.Current = box;
-
-        try
-        {
-            var response = await base.GetResponseAsync(messages, effectiveOptions, cancellationToken).ConfigureAwait(false);
-
-            if (box.Value is { } servedModel)
-            {
-                response.ModelId = servedModel;
-            }
-
-            return response;
-        }
-        finally
-        {
-            ServedModelScope.Current = previous;
-        }
-    }
-
-    /// <inheritdoc/>
-    public override async IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(IEnumerable<ChatMessage> messages, ChatOptions? options = null, [EnumeratorCancellation] CancellationToken cancellationToken = default)
-    {
-        var effectiveOptions = this._agentReference is not null
-            ? this.GetAgentEnabledChatOptions(options)
-            : options;
-
-        var box = new StrongBox<string?>(null);
-        var previous = ServedModelScope.Current;
-        ServedModelScope.Current = box;
-
-        try
-        {
-            await foreach (var chunk in base.GetStreamingResponseAsync(messages, effectiveOptions, cancellationToken).ConfigureAwait(false))
-            {
-                if (box.Value is { } servedModel)
-                {
-                    chunk.ModelId = servedModel;
-                }
-
-                yield return chunk;
-            }
-        }
-        finally
-        {
-            ServedModelScope.Current = previous;
-        }
-    }
-
-    #region File and vector-store helpers (mirrors Python's foundry_chat_client surface)
-
-    /// <summary>
-    /// Uploads a single file to the project for the supplied purpose. The upload is performed
-    /// against the project-level <see cref="AIProjectClient"/> reachable via
-    /// <see cref="GetService(Type, object?)"/>, so this method works uniformly across all three
-    /// FoundryChatClient construction modes.
-    /// </summary>
-    /// <param name="filePath">Absolute or relative path to the file to upload. The file must exist.</param>
-    /// <param name="purpose">The file upload purpose (e.g. <see cref="FileUploadPurpose.Assistants"/>).</param>
-    /// <param name="cancellationToken">A token that can cancel the upload.</param>
-    /// <returns>The created <see cref="OpenAIFile"/> as returned by the service.</returns>
-    /// <exception cref="ArgumentNullException"><paramref name="filePath"/> is <see langword="null"/>.</exception>
-    /// <exception cref="FileNotFoundException">The file at <paramref name="filePath"/> does not exist.</exception>
-    public async Task<OpenAIFile> UploadFileAsync(string filePath, FileUploadPurpose purpose, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNull(filePath);
-        if (!File.Exists(filePath))
-        {
-            throw new FileNotFoundException($"File not found: '{filePath}'.", filePath);
-        }
-
-        var fileClient = this.GetOpenAIFileClient();
-        // Use the Stream overload to honor cancellation; the (string, purpose) overload has no
-        // CancellationToken parameter in the OpenAI SDK.
-        using var stream = File.OpenRead(filePath);
-        var result = await fileClient.UploadFileAsync(stream, Path.GetFileName(filePath), purpose, cancellationToken).ConfigureAwait(false);
-        return result.Value;
-    }
-
-    /// <summary>Deletes a file previously uploaded to the project.</summary>
-    /// <param name="fileId">The file id returned by <see cref="UploadFileAsync(string, FileUploadPurpose, CancellationToken)"/>.</param>
-    /// <param name="cancellationToken">A token that can cancel the delete.</param>
-    /// <returns>The deletion result.</returns>
-    /// <exception cref="ArgumentException"><paramref name="fileId"/> is <see langword="null"/> or whitespace.</exception>
-    public async Task<FileDeletionResult> DeleteFileAsync(string fileId, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNullOrWhitespace(fileId);
-        var fileClient = this.GetOpenAIFileClient();
-        var result = await fileClient.DeleteFileAsync(fileId, cancellationToken).ConfigureAwait(false);
-        return result.Value;
-    }
-
-    /// <summary>
-    /// Uploads the supplied files, creates a vector store containing them, waits until the
-    /// store finishes ingesting its files (status leaves <see cref="VectorStoreStatus.InProgress"/>),
-    /// and returns the <see cref="VectorStore"/>. Mirrors Python's
-    /// <c>foundry_chat_client.create_vector_store(name, files, expires_after_days)</c>.
-    /// </summary>
-    /// <param name="name">The vector store name.</param>
-    /// <param name="filePaths">Paths to files to upload and attach to the store.</param>
-    /// <param name="expiresAfter">Optional last-active-at expiration window. When supplied, the vector store expires this many days after its last use.</param>
-    /// <param name="pollingTimeout">Optional upper bound on the wait for the vector store to leave <see cref="VectorStoreStatus.InProgress"/>. Defaults to 5 minutes when not supplied; pass <see cref="Timeout.InfiniteTimeSpan"/> to disable. Independent of <paramref name="cancellationToken"/>: cancellation always wins.</param>
-    /// <param name="cancellationToken">A token that can cancel the orchestration.</param>
-    /// <returns>The created and fully-ready <see cref="VectorStore"/>. The returned instance reflects the state observed after polling completes; it may be in <see cref="VectorStoreStatus.Completed"/> (typical), <see cref="VectorStoreStatus.Expired"/>, or any other terminal status returned by the service. Only <see cref="VectorStoreStatus.InProgress"/> is polled.</returns>
-    /// <remarks>
-    /// <para>
-    /// File-upload semantics are best-effort: when one of the per-file uploads throws, this method
-    /// makes a best-effort attempt to delete the files it has already uploaded so they do not
-    /// accumulate as orphaned resources on the project, then rethrows the original exception. The
-    /// cleanup itself does not throw — its failures are silently ignored because the caller is
-    /// already receiving a more meaningful exception from the original upload failure.
-    /// </para>
-    /// <para>
-    /// Cancellation aborts the polling loop with an <see cref="OperationCanceledException"/>; any
-    /// already-uploaded files and the partially-created vector store remain on the project and are
-    /// the caller's responsibility to clean up. The same applies when the polling timeout elapses
-    /// (a <see cref="TimeoutException"/> is thrown instead).
-    /// </para>
-    /// </remarks>
-    /// <exception cref="ArgumentException"><paramref name="name"/> is <see langword="null"/> or whitespace, or <paramref name="filePaths"/> is <see langword="null"/>.</exception>
-    /// <exception cref="TimeoutException">The vector store did not leave <see cref="VectorStoreStatus.InProgress"/> within <paramref name="pollingTimeout"/>.</exception>
-    public async Task<VectorStore> CreateVectorStoreAsync(string name, IEnumerable<string> filePaths, TimeSpan? expiresAfter = null, TimeSpan? pollingTimeout = null, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNullOrWhitespace(name);
-        Throw.IfNull(filePaths);
-
-        var fileIds = new List<string>();
-        try
-        {
-            foreach (var path in filePaths)
-            {
-                cancellationToken.ThrowIfCancellationRequested();
-                var uploaded = await this.UploadFileAsync(path, FileUploadPurpose.Assistants, cancellationToken).ConfigureAwait(false);
-                fileIds.Add(uploaded.Id);
-            }
-        }
-        catch
-        {
-            // Q-B: best-effort cleanup of files already uploaded before the mid-loop failure so
-            // they do not accumulate as orphaned resources on the project. Swallow cleanup
-            // exceptions — the caller is already going to see the original upload exception, and
-            // there is nothing useful we can do with a secondary delete failure.
-            await this.BestEffortDeleteFilesAsync(fileIds).ConfigureAwait(false);
-            throw;
-        }
-
-        var options = new VectorStoreCreationOptions
-        {
-            Name = name,
-        };
-        foreach (var id in fileIds)
-        {
-            options.FileIds.Add(id);
-        }
-        if (expiresAfter is { } window)
-        {
-            options.ExpirationPolicy = new VectorStoreExpirationPolicy(VectorStoreExpirationAnchor.LastActiveAt, (int)Math.Ceiling(window.TotalDays));
-        }
-
-        var vectorStoreClient = this.GetVectorStoreClient();
-        var createResult = await vectorStoreClient.CreateVectorStoreAsync(options, cancellationToken).ConfigureAwait(false);
-        var created = createResult.Value;
-
-        // Q-A: poll until the vector store leaves the in-progress state. Without this the helper
-        // hands the caller a vector store whose file ingestion may still be running, defeating
-        // the purpose of the one-call wrapper.
-        return await WaitForVectorStoreReadyAsync(vectorStoreClient, created, pollingTimeout ?? s_defaultPollingTimeout, cancellationToken).ConfigureAwait(false);
-    }
-
-    private async Task BestEffortDeleteFilesAsync(IEnumerable<string> fileIds)
-    {
-        foreach (var id in fileIds)
-        {
-            try
-            {
-                // Pass CancellationToken.None: cleanup runs in the catch path; the caller's
-                // token may already be cancelled and we still want to do our best to free
-                // orphaned resources before propagating the original exception.
-                await this.DeleteFileAsync(id, CancellationToken.None).ConfigureAwait(false);
-            }
-            catch
-            {
-                // Silently ignore cleanup failures; see XML doc on CreateVectorStoreAsync.
-            }
-        }
-    }
-
-    /// <summary>Upper bound on <see cref="WaitForVectorStoreReadyAsync"/> when the caller does not supply one. Chosen to comfortably cover normal Foundry vector-store ingestion (seconds to a minute for modest file sets) while still surfacing a clear failure if the server is stuck.</summary>
-    private static readonly TimeSpan s_defaultPollingTimeout = TimeSpan.FromMinutes(5);
-
-    private static async Task<VectorStore> WaitForVectorStoreReadyAsync(VectorStoreClient client, VectorStore initial, TimeSpan timeout, CancellationToken cancellationToken)
-    {
-        if (initial.Status != VectorStoreStatus.InProgress)
-        {
-            return initial;
-        }
-
-        var stopwatch = System.Diagnostics.Stopwatch.StartNew();
-        var delay = TimeSpan.FromMilliseconds(250);
-        var maxDelay = TimeSpan.FromSeconds(2);
-        var current = initial;
-        while (current.Status == VectorStoreStatus.InProgress)
-        {
-            if (timeout != Timeout.InfiniteTimeSpan && stopwatch.Elapsed >= timeout)
-            {
-                throw new TimeoutException(
-                    $"Vector store '{current.Id}' did not leave the in-progress state within {timeout.TotalSeconds:0.##} seconds.");
-            }
-
-            await Task.Delay(delay, cancellationToken).ConfigureAwait(false);
-            var refreshed = await client.GetVectorStoreAsync(current.Id, cancellationToken).ConfigureAwait(false);
-            current = refreshed.Value;
-
-            if (delay < maxDelay)
-            {
-                var next = TimeSpan.FromMilliseconds(delay.TotalMilliseconds * 2);
-                delay = next < maxDelay ? next : maxDelay;
-            }
-        }
-
-        return current;
-    }
-
-    /// <summary>Deletes a vector store. The associated files (if any) are not deleted by this method; call <see cref="DeleteFileAsync(string, CancellationToken)"/> separately to clean them up.</summary>
-    /// <param name="vectorStoreId">The vector store id.</param>
-    /// <param name="cancellationToken">A token that can cancel the delete.</param>
-    /// <returns>The deletion result.</returns>
-    /// <exception cref="ArgumentException"><paramref name="vectorStoreId"/> is <see langword="null"/> or whitespace.</exception>
-    public async Task<VectorStoreDeletionResult> DeleteVectorStoreAsync(string vectorStoreId, CancellationToken cancellationToken = default)
-    {
-        Throw.IfNullOrWhitespace(vectorStoreId);
-        var vectorStoreClient = this.GetVectorStoreClient();
-        var result = await vectorStoreClient.DeleteVectorStoreAsync(vectorStoreId, cancellationToken).ConfigureAwait(false);
-        return result.Value;
-    }
-
-    private OpenAIFileClient GetOpenAIFileClient()
-    {
-        var projectClient = this._aiProjectClient
-            ?? throw new InvalidOperationException("This FoundryChatClient does not have an AIProjectClient available. File and vector-store helpers require an AIProjectClient.");
-        return projectClient.GetProjectOpenAIClient().GetOpenAIFileClient();
-    }
-
-    private VectorStoreClient GetVectorStoreClient()
-    {
-        var projectClient = this._aiProjectClient
-            ?? throw new InvalidOperationException("This FoundryChatClient does not have an AIProjectClient available. File and vector-store helpers require an AIProjectClient.");
-        return projectClient.GetProjectOpenAIClient().GetVectorStoreClient();
-    }
-
-    #endregion
-
-    /// <summary>
-    /// Parses an agent endpoint URI of shape
-    /// <c>https://&lt;host&gt;/.../projects/&lt;project&gt;/agents/&lt;agentName&gt;/endpoint/protocols/openai</c>
-    /// and returns the agent name and the derived project-root URI.
-    /// </summary>
-    /// <remarks>
-    /// Tolerates trailing slash, casing variants on <c>/agents/</c> and the suffix segment, and
-    /// strips query string and fragment. Throws <see cref="ArgumentException"/> for inputs that
-    /// do not match the expected shape.
-    /// </remarks>
-    /// <exception cref="ArgumentException">
-    /// The endpoint is missing the <c>/agents/</c> segment, has an empty agent name, or has a
-    /// suffix other than <c>/endpoint/protocols/openai</c>.
-    /// </exception>
-    internal static (string AgentName, Uri ProjectRoot) ParseAgentEndpoint(Uri agentEndpoint)
-    {
-        Throw.IfNull(agentEndpoint);
-
-        const string AgentsSegment = "/agents/";
-        const string ExpectedSuffix = "/endpoint/protocols/openai";
-
-        var path = agentEndpoint.AbsolutePath.TrimEnd('/');
-        var idx = path.IndexOf(AgentsSegment, StringComparison.OrdinalIgnoreCase);
-        if (idx < 0)
-        {
-            throw new ArgumentException(
-                $"Expected an agent endpoint of shape 'https://<host>/.../projects/<project>/agents/<agentName>/endpoint/protocols/openai' but got '{agentEndpoint}'. " +
-                "If you want to construct a FoundryAgent against a project endpoint, use the (Uri projectEndpoint, AuthenticationTokenProvider credential, string model, string instructions, ...) constructor instead.",
-                nameof(agentEndpoint));
-        }
-
-        var afterAgents = path.Substring(idx + AgentsSegment.Length);
-        var nextSlash = afterAgents.IndexOf('/');
-        if (nextSlash <= 0)
-        {
-            throw new ArgumentException(
-                $"Agent endpoint '{agentEndpoint}' is missing the '<agentName>{ExpectedSuffix}' suffix.",
-                nameof(agentEndpoint));
-        }
-
-        var agentName = afterAgents.Substring(0, nextSlash);
-        var suffix = afterAgents.Substring(nextSlash);
-        if (!string.Equals(suffix, ExpectedSuffix, StringComparison.OrdinalIgnoreCase))
-        {
-            throw new ArgumentException(
-                $"Agent endpoint '{agentEndpoint}' has an unexpected suffix '{suffix}'. Expected '{ExpectedSuffix}'.",
-                nameof(agentEndpoint));
-        }
-
-        var rootPath = path.Substring(0, idx);
-        var projectRoot = new UriBuilder(agentEndpoint)
-        {
-            Path = rootPath,
-            Query = string.Empty,
-            Fragment = string.Empty,
-        }.Uri;
-
-        return (agentName, projectRoot);
-    }
-
-    private ChatOptions GetAgentEnabledChatOptions(ChatOptions? options)
-    {
-        // Start with a clone of the base chat options defined for the agent, if any.
-        ChatOptions agentEnabledChatOptions = this._baseChatOptions?.Clone() ?? new();
-
-        // Ignore per-request all options that can't be overridden.
-        agentEnabledChatOptions.Instructions = null;
-        agentEnabledChatOptions.Tools = null;
-        agentEnabledChatOptions.Temperature = null;
-        agentEnabledChatOptions.TopP = null;
-        agentEnabledChatOptions.PresencePenalty = null;
-        agentEnabledChatOptions.ResponseFormat = null;
-
-        // Use the conversation from the request, or the one defined at the client level.
-        agentEnabledChatOptions.ConversationId = options?.ConversationId ?? this._baseChatOptions?.ConversationId;
-
-        // Preserve the original RawRepresentationFactory.
-        var originalFactory = options?.RawRepresentationFactory;
-
-        agentEnabledChatOptions.RawRepresentationFactory = (client) =>
-        {
-            if (originalFactory?.Invoke(this) is not CreateResponseOptions responseCreationOptions)
-            {
-                responseCreationOptions = new CreateResponseOptions();
-            }
-
-            responseCreationOptions.Agent = this._agentReference;
-#pragma warning disable SCME0001 // Type is for evaluation purposes only and is subject to change or removal in future updates.
-            responseCreationOptions.Patch.Remove("$.model"u8);
-#pragma warning restore SCME0001
-
-            return responseCreationOptions;
-        };
-
-        return agentEnabledChatOptions;
-    }
-
-    private static AgentReference CreateAgentReference(ProjectsAgentVersion agentVersion)
-    {
-        // If the version is null, empty, or whitespace, use "latest" as the default. This handles
-        // cases where hosted agents (like MCP agents) may not have a version assigned.
-        var version = string.IsNullOrWhiteSpace(agentVersion.Version) ? "latest" : agentVersion.Version;
-        return new AgentReference(agentVersion.Name, version);
-    }
-
-    private static AgentEndpointInner BuildAgentEndpointInner(
-        Uri agentEndpoint,
-        AuthenticationTokenProvider credential,
-        ProjectOpenAIClientOptions? clientOptions)
-    {
-        Throw.IfNull(agentEndpoint);
-        Throw.IfNull(credential);
-
-        var (agentName, projectRoot) = ParseAgentEndpoint(agentEndpoint);
-
-        var perAgentOptions = clientOptions ?? new ProjectOpenAIClientOptions();
-        perAgentOptions.Endpoint = agentEndpoint;
-        perAgentOptions.AgentName = agentName;
-
-        var authPolicy = new BearerTokenPolicy(credential, AzureAiResourceScope);
-        var perAgentClient = new ProjectOpenAIClient(authPolicy, perAgentOptions);
-
-        var chatClient = perAgentClient.GetProjectResponsesClient().AsIChatClient();
-
-        // Materialize a project-level AIProjectClient from the parsed project root so
-        // GetService<AIProjectClient>() returns non-null for all FoundryChatClient
-        // construction modes. Project-level helpers (file upload, vector store create/delete)
-        // depend on this. RBAC for those calls is at the project level; if the supplied
-        // credential lacks project-scope permissions, the SDK surfaces a clean 401/403 at
-        // call time. The four observable primitive ClientPipelineOptions properties are
-        // propagated from the caller's per-agent options bag so test-injected transports and
-        // explicit RetryPolicy / NetworkTimeout / UserAgentApplicationId reach the
-        // project-level pipeline. Pipeline policies added via AddPolicy on the caller bag are
-        // NOT propagated because ClientPipelineOptions does not publicly enumerate policies.
-        var aiProjectClientOptions = new AIProjectClientOptions();
-        if (clientOptions is not null)
-        {
-            if (clientOptions.RetryPolicy is not null)
-            {
-                aiProjectClientOptions.RetryPolicy = clientOptions.RetryPolicy;
-            }
-            if (clientOptions.NetworkTimeout is not null)
-            {
-                aiProjectClientOptions.NetworkTimeout = clientOptions.NetworkTimeout;
-            }
-            if (clientOptions.Transport is not null)
-            {
-                aiProjectClientOptions.Transport = clientOptions.Transport;
-            }
-            if (!string.IsNullOrEmpty(clientOptions.UserAgentApplicationId))
-            {
-                aiProjectClientOptions.UserAgentApplicationId = clientOptions.UserAgentApplicationId;
-            }
-        }
-        var aiProjectClient = new AIProjectClient(projectRoot, credential, aiProjectClientOptions);
-
-        return new AgentEndpointInner(chatClient, aiProjectClient, agentName);
-    }
-
-    private static AgentEndpointInner BuildAgentEndpointInnerFromProjectClient(
-        AIProjectClient aiProjectClient,
-        Uri agentEndpoint,
-        ProjectOpenAIClientOptions? clientOptions)
-    {
-        Throw.IfNull(aiProjectClient);
-        Throw.IfNull(agentEndpoint);
-
-        var (agentName, _) = ParseAgentEndpoint(agentEndpoint);
-
-        var perAgentOptions = clientOptions ?? new ProjectOpenAIClientOptions();
-        perAgentOptions.Endpoint = agentEndpoint;
-        perAgentOptions.AgentName = agentName;
-
-        var chatClient = aiProjectClient.GetProjectOpenAIClient()
-            .GetProjectResponsesClientForAgentEndpoint(agentName, options: perAgentOptions)
-            .AsIChatClient();
-
-        // Reuse the caller's AIProjectClient verbatim — no new pipeline is materialized.
-        return new AgentEndpointInner(chatClient, aiProjectClient, agentName);
-    }
-
-    /// <summary>Best-effort registration of <see cref="AgentFrameworkUserAgentPolicy"/> via the MEAI <see cref="OpenAIRequestPolicies"/> hook with at-most-once dedup per pipeline.</summary>
-    private static void TryRegisterAgentFrameworkUserAgentPolicy(IChatClient? innerClient)
-    {
-        if (innerClient?.GetService<OpenAIRequestPolicies>() is { } policies)
-        {
-            // OpenAIRequestPoliciesReflection.AddPolicyIfMissing performs a check-then-add against
-            // the private _entries collection on the OpenAIRequestPolicies instance, so the
-            // policy is registered at most once even when many FoundryChatClient instances share
-            // the same underlying chat client.
-            OpenAIRequestPoliciesReflection.AddPolicyIfMissing(
-                policies,
-                AgentFrameworkUserAgentPolicy.Instance,
-                PipelinePosition.PerCall);
-        }
-    }
-
-    /// <summary>
-    /// Best-effort registration of <see cref="ServedModelPolicy"/> via the MEAI
-    /// <see cref="OpenAIRequestPolicies"/> hook. The policy captures the
-    /// <c>x-ms-served-model</c> response header from Azure OpenAI and writes it into
-    /// <see cref="ServedModelScope"/> so the <see cref="GetResponseAsync"/> and
-    /// <see cref="GetStreamingResponseAsync"/> overrides can overwrite
-    /// <see cref="ChatResponse.ModelId"/> with the actual model snapshot.
-    /// </summary>
-    private static void TryRegisterServedModelPolicy(IChatClient? innerClient)
-    {
-        if (innerClient?.GetService<OpenAIRequestPolicies>() is { } policies)
-        {
-            OpenAIRequestPoliciesReflection.AddPolicyIfMissing(
-                policies,
-                ServedModelPolicy.Instance,
-                PipelinePosition.PerCall);
-        }
-    }
-
-    /// <summary>Default OAuth scope for the Azure AI resource. Matches the scope used by <c>Azure.AI.Extensions.OpenAI</c>'s internal authentication helper so the bearer token is accepted by the Foundry control plane.</summary>
-    private const string AzureAiResourceScope = "https://ai.azure.com/.default";
-
-    private readonly struct AgentEndpointInner
-    {
-        public AgentEndpointInner(IChatClient chatClient, AIProjectClient aiProjectClient, string agentName)
-        {
-            this.ChatClient = chatClient;
-            this.AIProjectClient = aiProjectClient;
-            this.AgentName = agentName;
-        }
-
-        public IChatClient ChatClient { get; }
-        public AIProjectClient AIProjectClient { get; }
-        public string AgentName { get; }
-    }
-}
@@ -1,150 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Diagnostics.CodeAnalysis;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.DiagnosticIds;
-using Microsoft.Shared.Diagnostics;
-using OpenAI.Responses;
-
-#pragma warning disable OPENAI001
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// Shared internal implementation behind the public <c>ToPromptAgentAsync</c> extension methods
-/// on <see cref="ChatClientAgent"/> and <see cref="FoundryAgent"/>. Converts a Foundry-backed
-/// agent into a <see cref="ProjectsAgentDefinition"/> ready to publish via
-/// <see cref="AgentAdministrationClient"/>.
-/// </summary>
-/// <remarks>
-/// <para>
-/// Dispatch by <see cref="FoundryChatClient"/> construction mode (reachable via
-/// <see cref="IChatClient.GetService(Type, object?)"/>):
-/// </para>
-/// <list type="bullet">
-/// <item><description><b>Responses Agent (Mode 1)</b>: synthesize a <see cref="DeclarativeAgentDefinition"/> from the agent's <see cref="ChatOptions"/>.</description></item>
-/// <item><description><b>Prompt Agent (Mode 2, cached version)</b>: return the cached <see cref="ProjectsAgentVersion.Definition"/>.</description></item>
-/// <item><description><b>Prompt Agent (Mode 2, AgentReference-only)</b>: fetch the latest version from the service and return its definition.</description></item>
-/// <item><description><b>Agent Endpoint (Mode 3)</b>: throw — no local definition exists to convert.</description></item>
-/// </list>
-/// </remarks>
-[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
-internal static class FoundryPromptAgentConverter
-{
-    /// <summary>Performs the conversion for an agent whose chat client and chat options are supplied.</summary>
-    /// <param name="chatClient">The chat client extracted from the calling agent (must surface a <see cref="FoundryChatClient"/> via <see cref="IChatClient.GetService(Type, object?)"/>).</param>
-    /// <param name="chatOptions">The agent's chat options (model id, instructions, temperature, top-p, tools). Required for the Responses Agent mode; ignored for the Prompt Agent mode.</param>
-    /// <param name="cancellationToken">A token that can cancel a server-side fetch (Prompt Agent AgentReference path).</param>
-    /// <returns>A <see cref="ProjectsAgentDefinition"/> suitable for <c>AgentAdministrationClient.CreateAgentVersionAsync</c>.</returns>
-    /// <exception cref="InvalidOperationException">Thrown when the chat client is not Foundry-backed, the agent was constructed via the Agent Endpoint mode, no model id is set for the Responses Agent mode, or an unsupported <see cref="AITool"/> is encountered.</exception>
-    public static async Task<ProjectsAgentDefinition> ConvertAsync(IChatClient chatClient, ChatOptions? chatOptions, CancellationToken cancellationToken)
-    {
-        Throw.IfNull(chatClient);
-
-        var foundryChatClient = chatClient.GetService<FoundryChatClient>()
-            ?? throw new InvalidOperationException(
-                "ToPromptAgentAsync requires a FoundryChatClient-backed agent. " +
-                "The supplied agent's chat client does not expose a FoundryChatClient via GetService<FoundryChatClient>().");
-
-        // Prompt Agent (Mode 2) with a cached server-side version (constructed via ProjectsAgentVersion or ProjectsAgentRecord).
-        if (foundryChatClient.GetService<ProjectsAgentVersion>() is { } cachedVersion)
-        {
-            return cachedVersion.Definition;
-        }
-
-        // Prompt Agent (Mode 2) AgentReference-only: fetch the agent definition from the service.
-        // Honor a pinned AgentReference.Version when present (Q-C fix); fall back to the latest
-        // version only when the reference is unpinned ("", null, or "latest").
-        if (foundryChatClient.GetService<AgentReference>() is { } agentReference)
-        {
-            var aiProjectClient = foundryChatClient.GetService<AIProjectClient>()
-                ?? throw new InvalidOperationException(
-                    "Cannot fetch the agent version because the FoundryChatClient does not expose an AIProjectClient.");
-
-            if (!string.IsNullOrWhiteSpace(agentReference.Version)
-                && !string.Equals(agentReference.Version, "latest", StringComparison.OrdinalIgnoreCase))
-            {
-                var pinnedVersion = await aiProjectClient.AgentAdministrationClient
-                    .GetAgentVersionAsync(agentReference.Name, agentReference.Version, cancellationToken)
-                    .ConfigureAwait(false);
-                return pinnedVersion.Value.Definition;
-            }
-
-            var record = await aiProjectClient.AgentAdministrationClient
-                .GetAgentAsync(agentReference.Name, cancellationToken)
-                .ConfigureAwait(false);
-            return record.Value.GetLatestVersion().Definition;
-        }
-
-        // Agent Endpoint (Mode 3): AgentName is set (parsed from URL) but no AgentReference exists
-        // locally. The agent definition lives only on the server and is not retrievable through this
-        // chat client, so conversion is not supported here.
-        if (foundryChatClient.AgentName is not null)
-        {
-            throw new InvalidOperationException(
-                "ToPromptAgentAsync is not supported for agents constructed via the Agent Endpoint mode (Mode 3); " +
-                "no local definition exists to convert.");
-        }
-
-        // Responses Agent (Mode 1): synthesize from ChatOptions.
-        return SynthesizeFromChatOptions(chatOptions);
-    }
-
-    private static DeclarativeAgentDefinition SynthesizeFromChatOptions(ChatOptions? chatOptions)
-    {
-        if (chatOptions is null || string.IsNullOrWhiteSpace(chatOptions.ModelId))
-        {
-            throw new InvalidOperationException(
-                "ToPromptAgentAsync requires a model id on the agent's ChatOptions to synthesize a prompt agent definition.");
-        }
-
-        var definition = new DeclarativeAgentDefinition(chatOptions.ModelId!)
-        {
-            Instructions = chatOptions.Instructions,
-            Temperature = chatOptions.Temperature,
-            TopP = chatOptions.TopP,
-        };
-
-        if (chatOptions.Tools is { Count: > 0 } tools)
-        {
-            foreach (var tool in tools)
-            {
-                definition.Tools.Add(ConvertTool(tool));
-            }
-        }
-
-        return definition;
-    }
-
-    private static ResponseTool ConvertTool(AITool tool)
-    {
-        Throw.IfNull(tool);
-
-        if (tool is AIFunction function)
-        {
-            // strictModeEnabled is intentionally true to match the Python spec's
-            // default behavior. JsonSchema on AIFunction is a JsonElement; serialize via its
-            // string form so the payload matches what callers pass elsewhere in this codebase.
-            return ResponseTool.CreateFunctionTool(
-                function.Name,
-                BinaryData.FromString(function.JsonSchema.ToString() ?? "{}"),
-                strictModeEnabled: true,
-                function.Description);
-        }
-
-        if (tool.GetService(typeof(ResponseTool)) is ResponseTool responseTool)
-        {
-            return responseTool;
-        }
-
-        throw new InvalidOperationException(
-            $"Cannot convert AITool of type '{tool.GetType().Name}' to a ResponseTool. " +
-            "Only AIFunction and AITool instances that wrap a ResponseTool (such as those produced by FoundryAITool factories) are supported.");
-    }
-}
@@ -0,0 +1,58 @@
+// 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;
+
+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>Provides a pipeline policy that adds a "MEAI/x.y.z" user-agent header.</summary>
+    private sealed class MeaiUserAgentPolicy : PipelinePolicy
+    {
+        public static MeaiUserAgentPolicy Instance { get; } = new MeaiUserAgentPolicy();
+
+        private static readonly string s_userAgentValue = CreateUserAgentValue();
+
+        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        {
+            AddUserAgentHeader(message);
+            ProcessNext(message, pipeline, currentIndex);
+        }
+
+        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        {
+            AddUserAgentHeader(message);
+            return ProcessNextAsync(message, pipeline, currentIndex);
+        }
+
+        private static void AddUserAgentHeader(PipelineMessage message) =>
+            message.Request.Headers.Add("User-Agent", s_userAgentValue);
+
+        private static string CreateUserAgentValue()
+        {
+            const string Name = "MEAI";
+
+            if (typeof(MeaiUserAgentPolicy).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;
+        }
+    }
+}
@@ -1,67 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.ClientModel.Primitives;
-using System.Collections.Generic;
-using System.Threading.Tasks;
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// Pipeline policy that captures the <c>x-ms-served-model</c> response header from Azure OpenAI
-/// and stores it in <see cref="ServedModelScope"/> for consumption by <see cref="FoundryChatClient"/>.
-/// </summary>
-/// <remarks>
-/// <para>
-/// Azure OpenAI Responses API returns the deployment alias in <c>response.model</c> but the actual
-/// model snapshot (e.g. <c>gpt-5-nano-2025-08-07</c>) in the <c>x-ms-served-model</c> response header.
-/// This policy extracts the header after the HTTP roundtrip so the <see cref="FoundryChatClient"/>
-/// can overwrite <c>ChatResponse.ModelId</c> with the true model name.
-/// </para>
-/// <para>
-/// Registered once per <c>OpenAIRequestPolicies</c> instance via the MEAI 10.5.1 extension hook.
-/// When the header is absent (non-Azure endpoints), the scope is not set and the
-/// <see cref="FoundryChatClient"/> preserves the original model name.
-/// </para>
-/// </remarks>
-internal sealed class ServedModelPolicy : PipelinePolicy
-{
-    /// <summary>The Azure OpenAI response header that carries the actual served model name.</summary>
-    internal const string ServedModelHeader = "x-ms-served-model";
-
-    public static ServedModelPolicy Instance { get; } = new ServedModelPolicy();
-
-    private ServedModelPolicy()
-    {
-    }
-
-    public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-    {
-        ProcessNext(message, pipeline, currentIndex);
-        CaptureServedModel(message);
-    }
-
-    public override async ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-    {
-        await ProcessNextAsync(message, pipeline, currentIndex).ConfigureAwait(false);
-        CaptureServedModel(message);
-    }
-
-    private static void CaptureServedModel(PipelineMessage message)
-    {
-        if (message.Response is null)
-        {
-            return;
-        }
-
-        if (message.Response.Headers.TryGetValue(ServedModelHeader, out string? servedModel)
-            && !string.IsNullOrWhiteSpace(servedModel))
-        {
-            // Write into the box (reference-type mutation) so the value is visible to the
-            // FoundryChatClient that pushed the box before calling the inner client.
-            if (ServedModelScope.Current is { } box)
-            {
-                box.Value = servedModel.Trim();
-            }
-        }
-    }
-}
@@ -1,35 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Runtime.CompilerServices;
-using System.Threading;
-
-namespace Microsoft.Agents.AI.Foundry;
-
-/// <summary>
-/// AsyncLocal carrier that bridges the <c>x-ms-served-model</c> response header value from the
-/// <see cref="ServedModelPolicy"/> running inside the SCM transport pipeline up to the
-/// <see cref="FoundryChatClient"/> decorator.
-/// </summary>
-/// <remarks>
-/// <para>
-/// Because <see cref="AsyncLocal{T}"/> mutations inside a child <c>async</c> method do not propagate
-/// back to the caller (copy-on-write semantics), this scope uses <see cref="StrongBox{T}"/> as an
-/// indirection layer. The <see cref="FoundryChatClient"/> pushes a fresh box onto the scope
-/// before calling the inner client; the <see cref="ServedModelPolicy"/> writes into the box's
-/// <see cref="StrongBox{T}.Value"/> (a reference-type mutation visible to anyone holding the same box).
-/// After the inner call returns, the client reads the box's value.
-/// </para>
-/// </remarks>
-internal static class ServedModelScope
-{
-    private static readonly AsyncLocal<StrongBox<string?>?> s_current = new();
-
-    /// <summary>
-    /// Gets or sets the per-async-flow served model box.
-    /// </summary>
-    public static StrongBox<string?>? Current
-    {
-        get => s_current.Value;
-        set => s_current.Value = value;
-    }
-}
@@ -4,11 +4,7 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
-using System.Linq;
 using Microsoft.Agents.AI.Compaction;
-#if NET
-using Microsoft.Agents.AI.Tools.Shell;
-#endif
 using Microsoft.Extensions.AI;
 using Microsoft.Shared.DiagnosticIds;
 using Microsoft.Shared.Diagnostics;
@@ -204,14 +200,6 @@ public sealed class HarnessAgent : DelegatingAIAgent
            result.Tools.Add(new HostedWebSearchTool());
        }

-#if NET
-        if (options?.ShellExecutor is ShellExecutor shellExecutor)
-        {
-            result.Tools ??= [];
-            result.Tools.Add(shellExecutor.AsAIFunction());
-        }
-#endif
-
        return result;
    }

@@ -261,22 +249,6 @@ public sealed class HarnessAgent : DelegatingAIAgent
            providers.Add(skillsProvider);
        }

-        if (options?.BackgroundAgents is IEnumerable<AIAgent> backgroundAgents)
-        {
-            var materializedAgents = backgroundAgents.ToList();
-            if (materializedAgents.Count > 0)
-            {
-                providers.Add(new BackgroundAgentsProvider(materializedAgents, options.BackgroundAgentsProviderOptions));
-            }
-        }
-
-#if NET
-        if (options?.ShellExecutor is ShellExecutor shellExecutor)
-        {
-            providers.Add(new ShellEnvironmentProvider(shellExecutor, options.ShellEnvironmentProviderOptions));
-        }
-#endif
-
        if (options?.AIContextProviders is IEnumerable<AIContextProvider> userProviders)
        {
            providers.AddRange(userProviders);
@@ -2,9 +2,6 @@

 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-#if NET
-using Microsoft.Agents.AI.Tools.Shell;
-#endif
 using Microsoft.Extensions.AI;
 using Microsoft.Shared.DiagnosticIds;

@@ -221,49 +218,4 @@ public sealed class HarnessAgentOptions
    /// This property is ignored when <see cref="DisableOpenTelemetry"/> is <see langword="true"/>.
    /// </remarks>
    public string? OpenTelemetrySourceName { get; set; }
-
-    /// <summary>
-    /// Gets or sets the collection of background agents available for delegation via <see cref="BackgroundAgentsProvider"/>.
-    /// </summary>
-    /// <remarks>
-    /// When non-null and non-empty, a <see cref="BackgroundAgentsProvider"/> is automatically included in the
-    /// agent's context providers, enabling the agent to start, monitor, and retrieve results from background tasks.
-    /// When <see langword="null"/> or empty, no <see cref="BackgroundAgentsProvider"/> is configured.
-    /// Each agent in the collection must have a non-empty <see cref="AIAgent.Name"/> and names must be unique
-    /// (case-insensitive). If these requirements are not met, <see cref="BackgroundAgentsProvider"/> will throw
-    /// an <see cref="System.ArgumentException"/> during construction.
-    /// </remarks>
-    public IEnumerable<AIAgent>? BackgroundAgents { get; set; }
-
-    /// <summary>
-    /// Gets or sets optional configuration for the <see cref="BackgroundAgentsProvider"/>.
-    /// </summary>
-    /// <remarks>
-    /// Use this to customize instructions or agent list formatting for the background agents feature.
-    /// This property is ignored when <see cref="BackgroundAgents"/> is <see langword="null"/> or empty.
-    /// </remarks>
-    public BackgroundAgentsProviderOptions? BackgroundAgentsProviderOptions { get; set; }
-
-#if NET
-    /// <summary>
-    /// Gets or sets the shell executor used to enable shell tool and environment probing via <see cref="ShellEnvironmentProvider"/>.
-    /// </summary>
-    /// <remarks>
-    /// When non-null, a <see cref="ShellEnvironmentProvider"/> is automatically included in the agent's context
-    /// providers (injecting OS/shell/CWD information into the system prompt), and the executor's
-    /// <see cref="ShellExecutor.AsAIFunction"/> is registered as a callable tool.
-    /// When <see langword="null"/> (the default), no shell features are enabled.
-    /// </remarks>
-    public ShellExecutor? ShellExecutor { get; set; }
-
-    /// <summary>
-    /// Gets or sets optional configuration for the <see cref="ShellEnvironmentProvider"/>.
-    /// </summary>
-    /// <remarks>
-    /// Use this to customize which tools are probed, the probe timeout, shell family override,
-    /// or the instructions formatter.
-    /// This property is ignored when <see cref="ShellExecutor"/> is <see langword="null"/>.
-    /// </remarks>
-    public ShellEnvironmentProviderOptions? ShellEnvironmentProviderOptions { get; set; }
-#endif
 }
@@ -15,10 +15,6 @@
    <ProjectReference Include="..\Microsoft.Agents.AI\Microsoft.Agents.AI.csproj" />
  </ItemGroup>

-  <ItemGroup Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net8.0'))">
-    <ProjectReference Include="..\Microsoft.Agents.AI.Tools.Shell\Microsoft.Agents.AI.Tools.Shell.csproj" />
-  </ItemGroup>
-
  <PropertyGroup>
    <!-- NuGet Package Settings -->
    <Title>Microsoft Agent Framework Harness</Title>
@@ -1,61 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Collections.Generic;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.Diagnostics;
-using ModelContextProtocol.Client;
-using ModelContextProtocol.Protocol;
-
-namespace Microsoft.Agents.AI.Mcp;
-
-/// <summary>
-/// Extension methods on <see cref="McpClient"/> that expose MCP server tools to a Microsoft
-/// Agent Framework agent with optional long-running task (SEP-2663) handling.
-/// </summary>
-public static class McpClientTaskExtensions
-{
-    /// <summary>
-    /// Lists tools advertised by the connected MCP server and returns each as an
-    /// <see cref="AIFunction"/>. Tools that declare <see cref="ToolTaskSupport.Required"/>
-    /// are wrapped with task-aware behavior so an agent can transparently drive long-running
-    /// invocations. All other tools — including those that declare
-    /// <see cref="ToolTaskSupport.Optional"/> — are returned as-is, preserving inline
-    /// (synchronous) invocation semantics by default.
-    /// </summary>
-    /// <param name="client">The connected MCP client.</param>
-    /// <param name="options">
-    /// Options that control the task lifecycle for task-capable tools.
-    /// When <see langword="null"/>, defaults described on <see cref="McpTaskOptions"/> apply.
-    /// </param>
-    /// <param name="cancellationToken">Token used to cancel listing the server's tools.</param>
-    /// <returns>The tools, ready to pass to <c>AsAIAgent(tools: …)</c>.</returns>
-    public static async Task<IReadOnlyList<AIFunction>> ListAgentToolsWithTaskSupportAsync(
-        this McpClient client,
-        McpTaskOptions? options = null,
-        CancellationToken cancellationToken = default)
-    {
-        _ = Throw.IfNull(client);
-
-        McpTaskOptions effectiveOptions = options ?? new McpTaskOptions();
-
-        IList<McpClientTool> tools = await client.ListToolsAsync(cancellationToken: cancellationToken).ConfigureAwait(false);
-
-        AIFunction[] result = new AIFunction[tools.Count];
-        for (int i = 0; i < tools.Count; i++)
-        {
-            ToolTaskSupport? taskSupport = tools[i].ProtocolTool.Execution?.TaskSupport;
-            if (taskSupport is ToolTaskSupport.Required)
-            {
-                result[i] = new TaskAwareMcpClientAIFunction(client, tools[i], effectiveOptions);
-            }
-            else
-            {
-                result[i] = tools[i];
-            }
-        }
-
-        return result;
-    }
-}
@@ -1,39 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-
-namespace Microsoft.Agents.AI.Mcp;
-
-/// <summary>
-/// Configures how an MCP client wrapper drives the
-/// <see href="https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks">MCP tasks</see>
-/// lifecycle when an underlying server tool returns a <c>CreateTaskResult</c>.
-/// </summary>
-/// <remarks>
-/// <para>
-/// All members of this type are subject to change. The MCP task surface is experimental
-/// and tracks the in-flight specification.
-/// </para>
-/// </remarks>
-public sealed class McpTaskOptions
-{
-    /// <summary>
-    /// Gets or sets the time-to-live the wrapper attaches to a newly created server-side task.
-    /// </summary>
-    /// <remarks>
-    /// When <see langword="null"/> the wrapper omits the <c>ttl</c> hint and lets the server
-    /// pick its own value. The server's chosen TTL is always authoritative.
-    /// </remarks>
-    public TimeSpan? DefaultTimeToLive { get; set; }
-
-    /// <summary>
-    /// Gets or sets a value indicating whether the wrapper should send
-    /// <c>tasks/cancel</c> when the local <see cref="System.Threading.CancellationToken"/>
-    /// fires during a tool invocation.
-    /// </summary>
-    /// <remarks>
-    /// Defaults to <see langword="true"/>: a local cancellation means "the caller is giving up
-    /// on this tool invocation" and the server-side task has no further consumer.
-    /// </remarks>
-    public bool CancelRemoteTaskOnLocalCancellation { get; set; } = true;
-}
@@ -1,37 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFrameworks>$(TargetFrameworksCore)</TargetFrameworks>
-    <RootNamespace>Microsoft.Agents.AI.Mcp</RootNamespace>
-    <VersionSuffix>alpha</VersionSuffix>
-    <NoWarn>$(NoWarn);MEAI001;MCPEXP001</NoWarn>
-  </PropertyGroup>
-
-  <Import Project="$(RepoRoot)/dotnet/nuget/nuget-package.props" />
-
-  <PropertyGroup>
-    <InjectSharedThrow>true</InjectSharedThrow>
-    <InjectTrimAttributesOnLegacy>true</InjectTrimAttributesOnLegacy>
-  </PropertyGroup>
-
-  <PropertyGroup>
-    <Title>Microsoft Agent Framework MCP</Title>
-    <Description>Provides Microsoft Agent Framework support for Model Context Protocol (MCP), including long-running task (SEP-2663) integration for MCP clients.</Description>
-  </PropertyGroup>
-
-  <!-- Disable package validation baseline until the first release -->
-  <PropertyGroup>
-    <PackageValidationBaselineVersion />
-    <EnablePackageValidation>false</EnablePackageValidation>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.AI" />
-    <PackageReference Include="ModelContextProtocol" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <InternalsVisibleTo Include="Microsoft.Agents.AI.Mcp.UnitTests" />
-  </ItemGroup>
-
-</Project>
@@ -1,147 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Text.Json;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
-using Microsoft.Shared.Diagnostics;
-using ModelContextProtocol;
-using ModelContextProtocol.Client;
-using ModelContextProtocol.Protocol;
-
-namespace Microsoft.Agents.AI.Mcp;
-
-/// <summary>
-/// An <see cref="AIFunction"/> wrapper around an <see cref="McpClientTool"/> that drives the
-/// <see href="https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks">MCP long-running task</see>
-/// lifecycle (SEP-2663) on behalf of the agent's tool loop.
-/// </summary>
-/// <remarks>
-/// <para>
-/// The wrapper invokes the tool with task augmentation via
-/// <see cref="McpClient.CallToolAsTaskAsync"/>, polls to completion via
-/// <see cref="McpClient.PollTaskUntilCompleteAsync"/>, and fetches the result via
-/// <see cref="McpClient.GetTaskResultAsync"/>. The result is returned to the caller as a
-/// <see cref="JsonElement"/> containing the serialized <see cref="CallToolResult"/> — the
-/// same wire shape produced by <see cref="McpClientTool"/>.<see cref="AIFunction.InvokeAsync(AIFunctionArguments, CancellationToken)"/>
-/// so that downstream <see cref="FunctionResultContent"/> serialization is byte-identical to
-/// a non-task-augmented MCP tool call. The agent's function-calling loop is unaware that a
-/// task was used.
-/// </para>
-/// <para>
-/// This wrapper is intended to be applied only to tools whose
-/// <see cref="ToolExecution.TaskSupport"/> is <see cref="ToolTaskSupport.Required"/>
-/// (selected by <see cref="McpClientTaskExtensions.ListAgentToolsWithTaskSupportAsync"/>).
-/// As a defensive fallback, if the server still rejects the task-augmented call with
-/// <see cref="McpErrorCode.MethodNotFound"/> (e.g. because tool-level capabilities changed
-/// between <c>tools/list</c> and invocation), the wrapper transparently falls back to a
-/// non-augmented call through the inner <see cref="McpClientTool"/>.
-/// </para>
-/// </remarks>
-internal sealed class TaskAwareMcpClientAIFunction : AIFunction
-{
-    private readonly McpClient _client;
-    private readonly McpClientTool _inner;
-    private readonly McpTaskOptions _options;
-
-    internal TaskAwareMcpClientAIFunction(McpClient client, McpClientTool inner, McpTaskOptions options)
-    {
-        _ = Throw.IfNull(client);
-        _ = Throw.IfNull(inner);
-        _ = Throw.IfNull(options);
-
-        this._client = client;
-        this._inner = inner;
-        this._options = options;
-    }
-
-    /// <inheritdoc />
-    public override string Name => this._inner.Name;
-
-    /// <inheritdoc />
-    public override string Description => this._inner.Description;
-
-    /// <inheritdoc />
-    public override JsonElement JsonSchema => this._inner.JsonSchema;
-
-    /// <inheritdoc />
-    public override JsonElement? ReturnJsonSchema => this._inner.ReturnJsonSchema;
-
-    /// <inheritdoc />
-    public override JsonSerializerOptions JsonSerializerOptions => this._inner.JsonSerializerOptions;
-
-    /// <inheritdoc />
-    protected override async ValueTask<object?> InvokeCoreAsync(
-        AIFunctionArguments arguments,
-        CancellationToken cancellationToken)
-    {
-        _ = Throw.IfNull(arguments);
-
-        McpTaskMetadata? metadata = null;
-        if (this._options.DefaultTimeToLive is TimeSpan ttl)
-        {
-            metadata = new McpTaskMetadata { TimeToLive = ttl };
-        }
-
-        McpTask task;
-        try
-        {
-            task = await this._client.CallToolAsTaskAsync(
-                this._inner.Name,
-                arguments,
-                taskMetadata: metadata,
-                progress: null,
-                options: null,
-                cancellationToken: cancellationToken).ConfigureAwait(false);
-        }
-        catch (McpProtocolException ex) when (ex.ErrorCode == McpErrorCode.MethodNotFound)
-        {
-            // Defensive fallback: the server's advertised TaskSupport indicated this tool
-            // could be invoked as a task, but the server now rejects task augmentation for it
-            // (e.g. capability changed between tools/list and invocation). Fall back to a
-            // non-augmented call through the inner McpClientTool.
-            return await this._inner.InvokeAsync(arguments, cancellationToken).ConfigureAwait(false);
-        }
-
-        return await this.PollAndRetrieveResultAsync(task.TaskId, cancellationToken).ConfigureAwait(false);
-    }
-
-    private async Task<JsonElement> PollAndRetrieveResultAsync(string taskId, CancellationToken cancellationToken)
-    {
-        try
-        {
-            McpTask terminal = await this._client.PollTaskUntilCompleteAsync(taskId, options: null, cancellationToken).ConfigureAwait(false);
-
-            return terminal.Status switch
-            {
-                McpTaskStatus.Completed => await this._client.GetTaskResultAsync(taskId, options: null, cancellationToken).ConfigureAwait(false),
-                McpTaskStatus.Cancelled => throw new OperationCanceledException(FormatTerminalStatusMessage(taskId, terminal)),
-                _ => throw new InvalidOperationException(FormatTerminalStatusMessage(taskId, terminal)),// Failed (or any future non-terminal-but-unhandled status that the poll loop returns).
-            };
-        }
-        catch (OperationCanceledException) when (this._options.CancelRemoteTaskOnLocalCancellation && cancellationToken.IsCancellationRequested)
-        {
-            await this.TryCancelTaskAsync(taskId).ConfigureAwait(false);
-            throw;
-        }
-    }
-
-    private static string FormatTerminalStatusMessage(string taskId, McpTask terminal)
-        => string.IsNullOrEmpty(terminal.StatusMessage)
-            ? $"MCP task '{taskId}' ended in terminal status '{terminal.Status}'."
-            : $"MCP task '{taskId}' ended in terminal status '{terminal.Status}': {terminal.StatusMessage}";
-
-    private async Task TryCancelTaskAsync(string taskId)
-    {
-        try
-        {
-            using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
-            _ = await this._client.CancelTaskAsync(taskId, options: null, cts.Token).ConfigureAwait(false);
-        }
-        catch
-        {
-            // Best-effort cancellation; do not mask the original cancellation reason.
-        }
-    }
-}
@@ -248,7 +248,7 @@ public sealed class DockerShellExecutor : ShellExecutor
    /// Build the AIFunction for this tool.
    /// </summary>
    /// <remarks>
-    /// When <paramref name="requireApproval"/> is <see langword="true"/>
+    /// When <paramref name="requireApproval"/> is <see langword="null"/>
    /// (the default), the returned function is wrapped in
    /// <see cref="ApprovalRequiredAIFunction"/>. The caller must
    /// explicitly pass <see langword="false"/> to opt out of approval
@@ -259,12 +259,14 @@ public sealed class DockerShellExecutor : ShellExecutor
    /// <param name="name">Function name surfaced to the model.</param>
    /// <param name="description">Function description for the model.</param>
    /// <param name="requireApproval">
-    /// <see langword="true"/> (the default) wraps the function in
-    /// <see cref="ApprovalRequiredAIFunction"/>;
+    /// <see langword="true"/> or <see langword="null"/> (the default)
+    /// wraps the function in <see cref="ApprovalRequiredAIFunction"/>;
    /// <see langword="false"/> opts out and returns the raw function.
    /// </param>
-    public override AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true)
+    public AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool? requireApproval = null)
    {
+        var effectiveRequireApproval = requireApproval ?? true;
+
        description ??=
            "Execute a single shell command inside an isolated Docker container and return its " +
            "stdout, stderr, and exit code. The container has no network, no host filesystem access " +
@@ -290,7 +292,7 @@ public sealed class DockerShellExecutor : ShellExecutor
            },
            new AIFunctionFactoryOptions { Name = name, Description = description });

-        return requireApproval ? new ApprovalRequiredAIFunction(fn) : fn;
+        return effectiveRequireApproval ? new ApprovalRequiredAIFunction(fn) : fn;
    }

    /// <summary>
@@ -325,7 +325,7 @@ public sealed class LocalShellExecutor : ShellExecutor
    /// container where the tool itself is the boundary).
    /// </param>
    /// <returns>An <see cref="AIFunction"/> wrapping <see cref="RunAsync"/>.</returns>
-    public override AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true)
+    public AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true)
    {
        if (!requireApproval && !this._acknowledgeUnsafe)
        {
@@ -3,7 +3,6 @@
 using System;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;

 namespace Microsoft.Agents.AI.Tools.Shell;

@@ -66,20 +65,6 @@ public abstract class ShellExecutor : IAsyncDisposable
    /// <param name="cancellationToken">Cancellation token.</param>
    public abstract Task<ShellResult> RunAsync(string command, CancellationToken cancellationToken = default);

-    /// <summary>
-    /// Build an <see cref="AIFunction"/> bound to this executor, suitable for
-    /// registering with an agent as a callable tool.
-    /// </summary>
-    /// <param name="name">Function name visible to the model.</param>
-    /// <param name="description">Function description for the model.</param>
-    /// <param name="requireApproval">
-    /// When <see langword="true"/> (the default), wraps the function in
-    /// <see cref="ApprovalRequiredAIFunction"/> so every invocation requires
-    /// explicit user approval before executing.
-    /// </param>
-    /// <returns>An <see cref="AIFunction"/> wrapping <see cref="RunAsync"/>.</returns>
-    public abstract AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true);
-
    /// <inheritdoc />
    public abstract ValueTask DisposeAsync();
 }
@@ -22,13 +22,9 @@ internal static class AgentProviderExtensions
    {
        IAsyncEnumerable<AgentResponseUpdate> agentUpdates = agentProvider.InvokeAgentAsync(agentName, null, conversationId, inputMessages, inputArguments, cancellationToken);

-        // Determine whether the target conversation is the workflow conversation
-        // (used below to decide whether to mirror messages into the workflow conversation
-        // when an agent runs against a different conversation). The caller's autoSend
-        // value is honored as-is — when the workflow.yaml specifies autoSend: false the
-        // raw agent output must not be streamed to the caller, even when the agent is
-        // running on the workflow conversation.
+        // Enable "autoSend" behavior if this is the workflow conversation.
        bool isWorkflowConversation = context.IsWorkflowConversation(conversationId, out string? workflowConversationId);
+        autoSend |= isWorkflowConversation;

        // Process the agent response updates.
        List<AgentResponseUpdate> updates = [];
@@ -71,13 +71,6 @@ internal abstract class DeclarativeActionExecutor : Executor<ActionExecutorResul
    [SendsMessage(typeof(ActionExecutorResult))]
    public override async ValueTask HandleAsync(ActionExecutorResult message, IWorkflowContext context, CancellationToken cancellationToken = default)
    {
-        // Establish the Foundry ProductContext on the current async logical context before
-        // running any code that reads PropertyPath.VariableName / NamespaceAlias. ObjectModel
-        // resolves those lazily against AsyncLocal<ProductContext>; when the workflow is
-        // hosted (AsAIAgent + AddFoundryResponses) each HTTP request runs on a fresh logical
-        // context where the build-thread setting does not flow.
-        WorkflowDiagnostics.SetFoundryProduct();
-
        if (this.Model.Disabled)
        {
            Debug.WriteLine($"DISABLED {this.GetType().Name} [{this.Id}]");
@@ -192,16 +192,13 @@ internal sealed class InvokeAzureAgentExecutor(InvokeAzureAgent model, ResponseA

    private bool GetAutoSendValue()
    {
-        // AzureAgentOutput.AutoSend is never null — it returns a literal-false default
-        // when the YAML omits the field. Use AutoSendIsDefaultValue to distinguish an
-        // explicit autoSend value from the implicit default, and treat the implicit
-        // default as autoSend = true (the historical behavior for actions that omit
-        // autoSend or have no output block at all).
-        if (this.AgentOutput is { AutoSendIsDefaultValue: false } output)
+        if (this.AgentOutput?.AutoSend is null)
        {
-            return this.Evaluator.GetValue(output.AutoSend).Value;
+            return true;
        }

-        return true;
+        EvaluationResult<bool> autoSendResult = this.Evaluator.GetValue(this.AgentOutput.AutoSend);
+
+        return autoSendResult.Value;
    }
 }
@@ -1,6 +1,5 @@
 // Copyright (c) Microsoft. All rights reserved.

-using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text.Json;
@@ -104,24 +103,6 @@ internal sealed class InvokeFunctionToolExecutor(
        FunctionResultContent? matchingResult = functionResults
            .FirstOrDefault(r => r.CallId == this.Id);

-        // When the caller approved an approval-required function call but didn't execute it
-        // locally (the hosted Foundry scenario, where mcp_approval_response is converted to a
-        // ToolApprovalResponseContent only), invoke the registered AIFunction here so that the
-        // declarative workflow can capture the result and continue (e.g. for downstream
-        // SendActivity/PropertyPath consumers like {Local.Result}).
-        if (matchingResult is null)
-        {
-            ToolApprovalResponseContent? approval = response.Messages
-                .SelectMany(m => m.Contents)
-                .OfType<ToolApprovalResponseContent>()
-                .FirstOrDefault(r => r.RequestId == this.Id);
-
-            if (approval is { Approved: true })
-            {
-                matchingResult = await this.InvokeRegisteredFunctionAsync(cancellationToken).ConfigureAwait(false);
-            }
-        }
-
        if (matchingResult is not null)
        {
            // Store the result in output variable
@@ -260,48 +241,6 @@ internal sealed class InvokeFunctionToolExecutor(
        return conversationIdValue.Length == 0 ? null : conversationIdValue;
    }

-    private async ValueTask<FunctionResultContent?> InvokeRegisteredFunctionAsync(CancellationToken cancellationToken)
-    {
-        string functionName = this.GetFunctionName();
-        AIFunction? function = agentProvider.Functions?.FirstOrDefault(
-            f => string.Equals(f.Name, functionName, StringComparison.Ordinal));
-
-        if (function is null)
-        {
-            return new FunctionResultContent(this.Id, result: null)
-            {
-                Exception = new InvalidOperationException(
-                    $"Function '{functionName}' is not registered with the agent provider."),
-            };
-        }
-
-        Dictionary<string, object?>? arguments = this.GetArguments();
-        AIFunctionArguments? functionArguments = arguments is null ? null : new AIFunctionArguments(arguments);
-
-        object? result;
-        try
-        {
-            result = await function.InvokeAsync(functionArguments, cancellationToken).ConfigureAwait(false);
-        }
-        catch (Exception ex) when (ex is not OperationCanceledException)
-        {
-            return new FunctionResultContent(this.Id, result: null) { Exception = ex };
-        }
-
-        // Match FunctionInvokingChatClient's serialization: pass strings through as-is and
-        // JSON-serialize anything else so structured results remain consumable by downstream
-        // PropertyPath consumers such as {Local.RefundResult}. Use AIJsonUtilities so the
-        // same trim/AOT-friendly serializer chain used elsewhere in the framework is applied.
-        string serialized = result switch
-        {
-            null => string.Empty,
-            string s => s,
-            _ => JsonSerializer.Serialize(result, AIJsonUtilities.DefaultOptions.GetTypeInfo(result.GetType())),
-        };
-
-        return new FunctionResultContent(this.Id, serialized);
-    }
-
    private bool GetRequireApproval()
    {
        if (this.Model.RequireApproval is null)
@@ -314,16 +253,12 @@ internal sealed class InvokeFunctionToolExecutor(

    private bool GetAutoSendValue()
    {
-        // InvokeToolOutput.AutoSend is never null — it returns a literal-false default
-        // when the YAML omits the field. Use AutoSendIsDefaultValue to distinguish an
-        // explicit autoSend value from the implicit default, and treat the implicit
-        // default as autoSend = true (the historical behavior).
-        if (this.Model.Output is { AutoSendIsDefaultValue: false } output)
+        if (this.Model.Output?.AutoSend is null)
        {
-            return this.Evaluator.GetValue(output.AutoSend).Value;
+            return true;
        }

-        return true;
+        return this.Evaluator.GetValue(this.Model.Output.AutoSend).Value;
    }

    private Dictionary<string, object?>? GetArguments()
@@ -311,16 +311,12 @@ internal sealed class InvokeMcpToolExecutor(

    private bool GetAutoSendValue()
    {
-        // InvokeToolOutput.AutoSend is never null — it returns a literal-false default
-        // when the YAML omits the field. Use AutoSendIsDefaultValue to distinguish an
-        // explicit autoSend value from the implicit default, and treat the implicit
-        // default as autoSend = true (the historical behavior).
-        if (this.Model.Output is { AutoSendIsDefaultValue: false } output)
+        if (this.Model.Output?.AutoSend is null)
        {
-            return this.Evaluator.GetValue(output.AutoSend).Value;
+            return true;
        }

-        return true;
+        return this.Evaluator.GetValue(this.Model.Output.AutoSend).Value;
    }

    private string? GetConnectionName()
@@ -21,21 +21,12 @@ internal sealed class SendActivityExecutor(SendActivity model, WorkflowFormulaSt

            await context.AddEventAsync(new MessageActivityEvent(activityText.Trim()), cancellationToken).ConfigureAwait(false);

-            ChatMessage message = new(ChatRole.Assistant, activityText);
-
-            // Emit an AgentResponseUpdateEvent so chat protocols (e.g. AsAIAgent) receive the
-            // activity text as streaming chat content. This event is yielded by WorkflowSession
-            // unconditionally, mirroring how AgentProviderExtensions surfaces autoSend agent
-            // updates — without it, SendActivity output is dropped whenever the host runs with
-            // includeWorkflowOutputsInResponse = false (the default).
-            AgentResponseUpdate update = new(ChatRole.Assistant, activityText) { AuthorName = this.Id };
-            await context.AddEventAsync(new AgentResponseUpdateEvent(this.Id, update), cancellationToken).ConfigureAwait(false);
-
            // Route through YieldOutputAsync so the activity participates in the workflow's
            // output-filter pipeline. The runner currently special-cases AgentResponse to
-            // produce an AgentResponseEvent identical to the one we'd build by hand, which
-            // is the gated summary surfaced only when includeWorkflowOutputsInResponse = true.
-            AgentResponse response = new([message]);
+            // produce an AgentResponseEvent identical to the one we'd build by hand, so this
+            // is behavior-preserving today and forward-compatible if filtering is ever
+            // applied to agent responses.
+            AgentResponse response = new([new ChatMessage(ChatRole.Assistant, activityText)]);
            await context.YieldOutputAsync(response, cancellationToken).ConfigureAwait(false);
        }

@@ -1,229 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.IO;
-using System.Threading.Tasks;
-using AgentConformance.IntegrationTests.Support;
-using Azure.AI.Projects;
-using Azure.AI.Projects.Agents;
-using Microsoft.Agents.AI;
-using Microsoft.Agents.AI.Foundry;
-using OpenAI.Files;
-using OpenAI.Responses;
-using OpenAI.VectorStores;
-using Shared.IntegrationTests;
-
-namespace Foundry.IntegrationTests;
-
-/// <summary>
-/// Integration tests for the file and vector-store forwarder extensions on
-/// <see cref="FoundryAgent"/> declared in <see cref="FoundryAgentExtensions"/>. End-to-end
-/// counterparts of the unit tests in
-/// <c>FoundryAgentExtensionsTests</c> that exercise the live Foundry project pipeline.
-/// </summary>
-/// <remarks>
-/// Mirrors <see cref="FoundryVersionedAgentCreateTests.CreateAgent_CreatesAgentWithVectorStoresAsync(string)"/>
-/// in shape (file upload → vector store creation → FileSearchTool answer → cleanup), but routes
-/// every helper call through the new <see cref="FoundryAgent"/> extensions instead of the raw
-/// <c>projectOpenAIClient.GetProjectFilesClient()</c> / <c>GetProjectVectorStoresClient()</c>
-/// path. Skipped by default for the same reasons as the existing vector-store IT (cost and
-/// runtime); flip Skip to run manually after seeding the right Foundry project.
-/// </remarks>
-public class FoundryAgentExtensionsTests
-{
-    private readonly AIProjectClient _client = new(
-        new Uri(TestConfiguration.GetRequiredValue(TestSettings.AzureAIProjectEndpoint)),
-        TestAzureCliCredentials.CreateAzureCliCredential());
-
-    [Fact(Skip = "For manual testing only")]
-    public async Task UploadFileAsync_ViaAgentExtension_UploadsToProjectAsync()
-    {
-        // Arrange — non-versioned Responses Agent (Mode 1) so we do not have to provision a server-side agent.
-        var agent = this._client.AsAIAgent(
-            model: TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName),
-            instructions: "Be helpful.");
-        var foundryAgent = this.WrapAsFoundryAgent(agent);
-
-        var filePath = Path.GetTempFileName() + ".txt";
-        File.WriteAllText(filePath, "agent-extensions integration test payload");
-
-        OpenAIFile? uploaded = null;
-        try
-        {
-            // Act.
-            uploaded = await foundryAgent.UploadFileAsync(filePath, FileUploadPurpose.Assistants);
-
-            // Assert.
-            Assert.NotNull(uploaded);
-            Assert.False(string.IsNullOrEmpty(uploaded.Id));
-            Assert.Equal(Path.GetFileName(filePath), uploaded.Filename);
-        }
-        finally
-        {
-            if (uploaded is not null)
-            {
-                await foundryAgent.DeleteFileAsync(uploaded.Id);
-            }
-
-            File.Delete(filePath);
-        }
-    }
-
-    [Fact(Skip = "For manual testing only")]
-    public async Task DeleteFileAsync_ViaAgentExtension_RemovesUploadedFileAsync()
-    {
-        var agent = this._client.AsAIAgent(
-            model: TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName),
-            instructions: "Be helpful.");
-        var foundryAgent = this.WrapAsFoundryAgent(agent);
-
-        var filePath = Path.GetTempFileName() + ".txt";
-        File.WriteAllText(filePath, "delete-me payload");
-
-        try
-        {
-            var uploaded = await foundryAgent.UploadFileAsync(filePath, FileUploadPurpose.Assistants);
-
-            // Act.
-            var result = await foundryAgent.DeleteFileAsync(uploaded.Id);
-
-            // Assert.
-            Assert.NotNull(result);
-            Assert.Equal(uploaded.Id, result.FileId);
-            Assert.True(result.Deleted);
-        }
-        finally
-        {
-            File.Delete(filePath);
-        }
-    }
-
-    [Fact(Skip = "For manual testing only")]
-    public async Task CreateVectorStoreAsync_ViaAgentExtension_BuildsStoreAndAnswersFileSearchQuestionAsync()
-    {
-        // Mirrors CreateAgent_CreatesAgentWithVectorStoresAsync but the upload-then-create-store
-        // sequence routes through the FoundryAgent.CreateVectorStoreAsync extension (single call
-        // that uploads, creates the store, and polls until ready). The resulting vector store id
-        // is then wired to a versioned agent's FileSearch tool and queried for a known value.
-        string AgentName = FoundryVersionedAgentFixture.GenerateUniqueAgentName("VectorStoreExtAgent");
-        const string AgentInstructions = """
-            You are a helpful agent that can help fetch data from files you know about.
-            Use the File Search Tool to look up codes for words.
-            Do not answer a question unless you can find the answer using the File Search Tool.
-            """;
-
-        // Non-versioned helper agent that owns the upload pipeline.
-        var helperAgent = this._client.AsAIAgent(
-            model: TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName),
-            instructions: "Be helpful.");
-        var helperFoundryAgent = this.WrapAsFoundryAgent(helperAgent);
-
-        var searchFilePath = Path.GetTempFileName() + "wordcodelookup.txt";
-        File.WriteAllText(searchFilePath, "The word 'apple' uses the code 442345, while the word 'banana' uses the code 673457.");
-
-        VectorStore? vectorStore = null;
-        FoundryAgent? versionedAgent = null;
-        try
-        {
-            // Act — single agent-level helper call uploads, creates, and waits until ready.
-            vectorStore = await helperFoundryAgent.CreateVectorStoreAsync(
-                "WordCodeLookup_ExtensionVectorStore",
-                new[] { searchFilePath });
-
-            Assert.NotNull(vectorStore);
-            Assert.False(string.IsNullOrEmpty(vectorStore.Id));
-            Assert.NotEqual(VectorStoreStatus.InProgress, vectorStore.Status);
-
-            // Wire the store id into a versioned agent's FileSearch tool to prove it is actually usable.
-            var definition = new DeclarativeAgentDefinition(TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName))
-            {
-                Instructions = AgentInstructions,
-                Tools = { ResponseTool.CreateFileSearchTool(vectorStoreIds: [vectorStore.Id]) },
-            };
-
-            var agentVersion = await this._client.AgentAdministrationClient.CreateAgentVersionAsync(
-                AgentName,
-                new ProjectsAgentVersionCreationOptions(definition));
-
-            versionedAgent = this._client.AsAIAgent(agentVersion);
-
-            // Assert.
-            var result = await versionedAgent.RunAsync("Can you give me the documented code for 'banana'?");
-            Assert.Contains("673457", result.ToString());
-        }
-        finally
-        {
-            if (versionedAgent is not null)
-            {
-                await this._client.AgentAdministrationClient.DeleteAgentAsync(versionedAgent.Name);
-            }
-
-            // Cleanup the vector store via the new extension too.
-            if (vectorStore is not null)
-            {
-                await helperFoundryAgent.DeleteVectorStoreAsync(vectorStore.Id);
-            }
-
-            File.Delete(searchFilePath);
-        }
-    }
-
-    [Fact(Skip = "For manual testing only")]
-    public async Task DeleteVectorStoreAsync_ViaAgentExtension_RemovesStoreAsync()
-    {
-        var agent = this._client.AsAIAgent(
-            model: TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName),
-            instructions: "Be helpful.");
-        var foundryAgent = this.WrapAsFoundryAgent(agent);
-
-        var filePath = Path.GetTempFileName() + ".txt";
-        File.WriteAllText(filePath, "delete-store payload");
-
-        VectorStore? vectorStore = null;
-        try
-        {
-            vectorStore = await foundryAgent.CreateVectorStoreAsync(
-                "DeleteVectorStore_ExtensionTest",
-                new[] { filePath });
-
-            // Act.
-            var result = await foundryAgent.DeleteVectorStoreAsync(vectorStore.Id);
-
-            // Assert.
-            Assert.NotNull(result);
-            Assert.Equal(vectorStore.Id, result.VectorStoreId);
-            Assert.True(result.Deleted);
-            vectorStore = null;
-        }
-        finally
-        {
-            if (vectorStore is not null)
-            {
-                await foundryAgent.DeleteVectorStoreAsync(vectorStore.Id);
-            }
-
-            File.Delete(filePath);
-        }
-    }
-
-    /// <summary>
-    /// Resolves the underlying <see cref="FoundryAgent"/> from an <see cref="AIAgent"/> handle
-    /// returned by <c>AIProjectClient.AsAIAgent(model, instructions)</c>. The Mode 1 overload
-    /// returns a <see cref="ChatClientAgent"/>; the extension forwarders we test live on
-    /// <see cref="FoundryAgent"/>, so callers wanting them through this entry point need to
-    /// reach for the FoundryAgent constructor instead. This helper makes the test setup
-    /// consistent across the four IT scenarios.
-    /// </summary>
-    private FoundryAgent WrapAsFoundryAgent(AIAgent agent)
-    {
-        // The Mode 1 AsAIAgent overload returns ChatClientAgent rather than FoundryAgent; use
-        // the FoundryAgent projectEndpoint+model+instructions ctor to get the same underlying
-        // FoundryChatClient surfaced through a FoundryAgent typed handle.
-        _ = agent;
-        return new FoundryAgent(
-            projectEndpoint: new Uri(TestConfiguration.GetRequiredValue(TestSettings.AzureAIProjectEndpoint)),
-            credential: TestAzureCliCredentials.CreateAzureCliCredential(),
-            model: TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName),
-            instructions: "Be helpful.");
-    }
-}
@@ -11,7 +11,7 @@ namespace Foundry.IntegrationTests;
 public class FoundryVersionedAgentStructuredOutputRunTests() : StructuredOutputRunTests<FoundryVersionedAgentStructuredOutputFixture<CityInfo>>(() => new FoundryVersionedAgentStructuredOutputFixture<CityInfo>())
 {
    private const string NotSupported = "Versioned Foundry agents do not support specifying structured output type at invocation time.";
-    private const string ResponseFormatNotSupported = "FoundryChatClient clears ResponseFormat for versioned agents; structured output must be defined in the server-side agent definition.";
+    private const string ResponseFormatNotSupported = "AzureAIProjectChatClient clears ResponseFormat for versioned agents; structured output must be defined in the server-side agent definition.";

    /// <summary>
    /// Verifies that response format provided at agent initialization is used when invoking RunAsync.
@@ -41,7 +41,7 @@ public class FoundryVersionedAgentStructuredOutputRunTests() : StructuredOutputR
    /// </summary>
    /// <remarks>
    /// Versioned Foundry agents do not support specifying the structured output type at invocation time yet.
-    /// The type T provided to RunAsync&lt;T&gt; is ignored by FoundryChatClient and is only used
+    /// The type T provided to RunAsync&lt;T&gt; is ignored by AzureAIProjectChatClient and is only used
    /// for deserializing the agent response by AgentResponse&lt;T&gt;.Result.
    /// </remarks>
    [RetryFact(Constants.RetryCount, Constants.RetryDelay, Skip = ResponseFormatNotSupported)]
@@ -1,85 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Text.RegularExpressions;
-using System.Threading.Tasks;
-using AgentConformance.IntegrationTests.Support;
-using Azure.AI.Projects;
-using Microsoft.Agents.AI;
-using Microsoft.Extensions.AI;
-using Shared.IntegrationTests;
-
-namespace Foundry.IntegrationTests;
-
-/// <summary>
-/// Integration tests validating that the <c>x-ms-served-model</c> response header
-/// returned by the Azure OpenAI Responses API is surfaced on <see cref="ChatResponse.ModelId"/>.
-/// </summary>
-public class ResponsesAgentServedModelTests
-{
-    // Matches a dated served-model snapshot, e.g. "gpt-5-nano-2025-08-07".
-    private static readonly Regex s_snapshotRegex = new(@"-\d{4}-\d{2}-\d{2}$", RegexOptions.Compiled);
-
-    private static Uri Endpoint => new(TestConfiguration.GetRequiredValue(TestSettings.AzureAIProjectEndpoint));
-
-    private static string DeploymentName => TestConfiguration.GetRequiredValue(TestSettings.AzureAIModelDeploymentName);
-
-    private readonly AIProjectClient _client = new(Endpoint, TestAzureCliCredentials.CreateAzureCliCredential());
-
-    [Fact]
-    public async Task GetResponseAsync_ReturnsServedModelSnapshotOnModelIdAsync()
-    {
-        // Arrange
-        ChatClientAgent agent = this._client.AsAIAgent(
-            model: DeploymentName,
-            instructions: "You are a helpful assistant. Reply with a single short word.",
-            name: "ServedModelTest");
-
-        IChatClient chatClient = agent.ChatClient;
-
-        // Act
-        ChatResponse response = await chatClient.GetResponseAsync(
-            [new ChatMessage(ChatRole.User, "Say hi.")],
-            new ChatOptions { ModelId = DeploymentName });
-
-        // Assert
-        AssertServedModel(response.ModelId);
-    }
-
-    [Fact]
-    public async Task RunAsync_AgentResponseRawRepresentationCarriesServedModelAsync()
-    {
-        // Arrange
-        ChatClientAgent agent = this._client.AsAIAgent(
-            model: DeploymentName,
-            instructions: "You are a helpful assistant. Reply with a single short word.",
-            name: "ServedModelTestRun");
-
-        // Act
-        AgentResponse agentResponse = await agent.RunAsync("Say hi.");
-
-        // Assert
-        ChatResponse? chatResponse = agentResponse.RawRepresentation as ChatResponse;
-        Assert.NotNull(chatResponse);
-        AssertServedModel(chatResponse!.ModelId);
-    }
-
-    private static void AssertServedModel(string? modelId)
-    {
-        Assert.False(string.IsNullOrWhiteSpace(modelId), "ChatResponse.ModelId must be populated.");
-
-        // Primary invariant: the served-model value must look like a dated snapshot
-        // (e.g. "gpt-5-nano-2025-08-07"). This is what the x-ms-served-model header carries.
-        // Only when the configured deployment name itself already matches the snapshot pattern
-        // do we fall back to permitting equality with the deployment alias.
-        bool aliasIsSnapshot = s_snapshotRegex.IsMatch(DeploymentName);
-
-        if (aliasIsSnapshot)
-        {
-            return;
-        }
-
-        Assert.Matches(s_snapshotRegex, modelId!);
-        Assert.NotEqual(DeploymentName, modelId);
-    }
-}
@@ -1124,7 +1124,6 @@ public sealed class A2AAgentTests : IDisposable
        Assert.Equal(TaskId, update0.ResponseId);
        Assert.Equal(this._agent.Id, update0.AgentId);
        Assert.Null(update0.FinishReason);
-        Assert.Null(update0.MessageId);
        Assert.IsType<TaskStatusUpdateEvent>(update0.RawRepresentation);

        // Assert - session should be updated with context and task IDs
@@ -1133,50 +1132,6 @@ public sealed class A2AAgentTests : IDisposable
        Assert.Equal(TaskId, a2aSession.TaskId);
    }

-    [Fact]
-    public async Task RunStreamingAsync_WithTaskStatusUpdateEventAndMessageId_YieldsMessageIdAsync()
-    {
-        // Arrange
-        const string TaskId = "task-status-msg-123";
-        const string ContextId = "ctx-status-msg-456";
-        const string ExpectedMessageId = "msg-status-789";
-
-        this._handler.StreamingResponseToReturn = new StreamResponse
-        {
-            StatusUpdate = new TaskStatusUpdateEvent
-            {
-                TaskId = TaskId,
-                ContextId = ContextId,
-                Status = new()
-                {
-                    State = TaskState.Working,
-                    Message = new Message
-                    {
-                        MessageId = ExpectedMessageId,
-                        Parts = [Part.FromText("Processing your request...")]
-                    }
-                }
-            }
-        };
-
-        var session = await this._agent.CreateSessionAsync();
-
-        // Act
-        var updates = new List<AgentResponseUpdate>();
-        await foreach (var update in this._agent.RunStreamingAsync("Check task status", session))
-        {
-            updates.Add(update);
-        }
-
-        // Assert
-        Assert.Single(updates);
-
-        var update0 = updates[0];
-        Assert.Equal(ExpectedMessageId, update0.MessageId);
-        Assert.Equal(TaskId, update0.ResponseId);
-        Assert.IsType<TaskStatusUpdateEvent>(update0.RawRepresentation);
-    }
-
    [Fact]
    public async Task RunStreamingAsync_WithInputRequiredStatusUpdate_YieldsStatusContentsAsync()
    {
@@ -1195,7 +1150,6 @@ public sealed class A2AAgentTests : IDisposable
                    State = TaskState.InputRequired,
                    Message = new Message
                    {
-                        MessageId = "input-msg-789",
                        Parts = [Part.FromText("Where would you like to fly?")]
                    }
                }
@@ -1216,7 +1170,6 @@ public sealed class A2AAgentTests : IDisposable

        var update0 = updates[0];
        Assert.Equal(TaskId, update0.ResponseId);
-        Assert.Equal("input-msg-789", update0.MessageId);
        Assert.Null(update0.FinishReason);

        var textContent = Assert.Single(update0.Contents.OfType<TextContent>());
@@ -64,29 +64,15 @@ public sealed class HostedOutboundUserAgentTests : IAsyncDisposable
        var inboundBody = await inboundResponse.Content.ReadAsStringAsync();

        // Assert: at least one OUTBOUND request reached the fake transport, AND it carries the
-        // combined hosted segment foundry-hosting/agent-framework-dotnet/{version} on its
-        // User-Agent. This matches Python's contract
-        // (foundry-hosting/agent-framework-python/{version}, see
-        // python/packages/core/agent_framework/_telemetry.py): a single combined segment when
-        // hosted, never two separate ones. The bare agent-framework-dotnet/{version} segment
-        // (from AgentFrameworkUserAgentPolicy in FoundryChatClient) must be upgraded in place
-        // by HostedAgentUserAgentPolicy — never appear duplicated.
+        // 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);
-
-        // The bare agent-framework-dotnet/{v} segment must NOT appear separately when the
-        // combined form is present — Python emits a single combined value when the hosted
-        // prefix is registered, and .NET preserves that contract via the in-place upgrade in
-        // HostedAgentUserAgentPolicy.
-        var combinedIdx = outbound.UserAgent!.IndexOf("foundry-hosting/agent-framework-dotnet/", StringComparison.Ordinal);
-        var beforeCombined = outbound.UserAgent.Substring(0, combinedIdx);
-        var afterCombined = outbound.UserAgent.Substring(combinedIdx + "foundry-hosting/agent-framework-dotnet/".Length);
-        Assert.DoesNotContain("agent-framework-dotnet/", beforeCombined);
-        Assert.DoesNotContain("agent-framework-dotnet/", afterCombined);
+        Assert.Contains("foundry-hosting/agent-framework-dotnet", outbound.UserAgent);
    }

    private async Task StartHostedServerAsync()
@@ -211,179 +197,6 @@ public sealed class HostedOutboundUserAgentTests : IAsyncDisposable
        return array?.Length ?? -1;
    }

-    // -----------------------------------------------------------------------
-    // Direct unit tests for HostedAgentUserAgentPolicy's in-place upgrade behavior.
-    // These run the policy on a synthetic ClientPipeline (no hosting infrastructure)
-    // so the upgrade logic itself can be asserted in isolation.
-    // -----------------------------------------------------------------------
-
-    [Fact]
-    public async Task HostedAgentUserAgentPolicy_UpgradesBareAgentFrameworkSegment_InPlaceAsync()
-    {
-        // Arrange: an upstream per-call policy stamps the bare agent-framework-dotnet/{version}
-        // segment (matching what AgentFrameworkUserAgentPolicy would write in non-hosted code).
-        // Then HostedAgentUserAgentPolicy runs and must REPLACE that segment with the combined
-        // foundry-hosting/agent-framework-dotnet/{version} form, not append a duplicate.
-        using var handler = new InspectingHandler();
-#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: [new SetUserAgentPolicy("agent-framework-dotnet/9.9.9"), HostedAgentUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert: combined form is present; bare form is gone (no duplicate agent-framework segment).
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.Contains("foundry-hosting/agent-framework-dotnet/", handler.LastUserAgent);
-        var ua = handler.LastUserAgent!;
-        var firstAgentFramework = ua.IndexOf("agent-framework-dotnet/", StringComparison.Ordinal);
-        Assert.True(firstAgentFramework >= 0, "Expected agent-framework-dotnet segment.");
-        var secondAgentFramework = ua.IndexOf("agent-framework-dotnet/", firstAgentFramework + 1, StringComparison.Ordinal);
-        Assert.Equal(-1, secondAgentFramework);
-    }
-
-    [Fact]
-    public async Task HostedAgentUserAgentPolicy_AppendsCombined_WhenNoBareSegmentPresentAsync()
-    {
-        // Arrange: nothing upstream stamps the bare segment. Hosted policy should append the
-        // full combined segment to whatever User-Agent is on the wire.
-        using var handler = new InspectingHandler();
-#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: [HostedAgentUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.Contains("foundry-hosting/agent-framework-dotnet/", handler.LastUserAgent);
-    }
-
-    [Fact]
-    public async Task HostedAgentUserAgentPolicy_IsIdempotent_WhenCombinedSegmentAlreadyPresentAsync()
-    {
-        // Arrange: upstream pre-populates the combined segment (simulating a retry or duplicate
-        // registration). Hosted policy must not re-append.
-        using var handler = new InspectingHandler();
-#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: [new SetUserAgentPolicy("foundry-hosting/agent-framework-dotnet/9.9.9"), HostedAgentUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert: exactly one occurrence of "foundry-hosting/agent-framework-dotnet/" segment.
-        Assert.NotNull(handler.LastUserAgent);
-        var first = handler.LastUserAgent!.IndexOf("foundry-hosting/agent-framework-dotnet/", StringComparison.Ordinal);
-        Assert.True(first >= 0);
-        var second = handler.LastUserAgent.IndexOf("foundry-hosting/agent-framework-dotnet/", first + 1, StringComparison.Ordinal);
-        Assert.Equal(-1, second);
-    }
-
-    [Fact]
-    public async Task HostedAgentUserAgentPolicy_ReplacesDifferentVersionCombinedSegment_InPlaceAsync()
-    {
-        // Q-D regression: when the User-Agent already carries the COMBINED hosted form with a
-        // different version (e.g. an older registration or caller-supplied baseline), the policy
-        // must replace the entire combined span — not just the bare suffix — so we never emit
-        // the malformed `foundry-hosting/foundry-hosting/agent-framework-dotnet/...` shape.
-        using var handler = new InspectingHandler();
-#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: [new SetUserAgentPolicy("foundry-hosting/agent-framework-dotnet/0.0.1 MEAI/10.5.1"), HostedAgentUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert: no doubled foundry-hosting/ prefix.
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.DoesNotContain("foundry-hosting/foundry-hosting/", handler.LastUserAgent, StringComparison.Ordinal);
-
-        // The combined segment must appear exactly once, and the trailing MEAI segment must be
-        // preserved in place (i.e. the policy only rewrote the combined span, not anything after it).
-        var firstCombined = handler.LastUserAgent!.IndexOf("foundry-hosting/agent-framework-dotnet/", StringComparison.Ordinal);
-        Assert.True(firstCombined >= 0);
-        var secondCombined = handler.LastUserAgent.IndexOf("foundry-hosting/agent-framework-dotnet/", firstCombined + 1, StringComparison.Ordinal);
-        Assert.Equal(-1, secondCombined);
-        Assert.Contains(" MEAI/10.5.1", handler.LastUserAgent, StringComparison.Ordinal);
-
-        // And the version that survives must be the runtime supplement value's version, not 0.0.1.
-        Assert.DoesNotContain("foundry-hosting/agent-framework-dotnet/0.0.1", handler.LastUserAgent, StringComparison.Ordinal);
-    }
-
-    private sealed class InspectingHandler : HttpClientHandler
-    {
-        public string? LastUserAgent { get; private set; }
-
-        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
-        {
-            this.LastUserAgent = request.Headers.TryGetValues("User-Agent", out var values)
-                ? string.Join(",", values)
-                : null;
-
-            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent("{}", Encoding.UTF8, "application/json"),
-                RequestMessage = request,
-            });
-        }
-    }
-
-    private sealed class SetUserAgentPolicy : PipelinePolicy
-    {
-        private readonly string _value;
-        public SetUserAgentPolicy(string value) => this._value = value;
-
-        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-        {
-            message.Request.Headers.Set("User-Agent", this._value);
-            ProcessNext(message, pipeline, currentIndex);
-        }
-
-        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-        {
-            message.Request.Headers.Set("User-Agent", this._value);
-            return ProcessNextAsync(message, pipeline, currentIndex);
-        }
-    }
-
    private sealed class NoopHandler : HttpMessageHandler
    {
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
@@ -1,199 +0,0 @@
-// 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.Reflection;
-using System.Text;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Verifies the framework-wide <see cref="AgentFrameworkUserAgentPolicy"/>. The policy stamps
-/// <c>agent-framework-dotnet/{version}</c> onto the outgoing <c>User-Agent</c> header of every
-/// request made through a Foundry chat client and is registered automatically by
-/// <c>FoundryChatClient</c> via the MEAI <c>OpenAIRequestPolicies</c> hook.
-/// </summary>
-public sealed class AgentFrameworkUserAgentPolicyTests
-{
-    [Fact]
-    public async Task AgentFrameworkUserAgentPolicy_AddsAgentFrameworkSegment_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: [AgentFrameworkUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert
-        Assert.Equal(1, handler.Count);
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.Contains("agent-framework-dotnet/", handler.LastUserAgent);
-    }
-
-    [Fact]
-    public async Task AgentFrameworkUserAgentPolicy_DoesNotStampMeaiSegmentAsync()
-    {
-        // Arrange: the AF policy must only contribute the agent-framework-dotnet segment.
-        // The MEAI/{version} segment is contributed by the MEAI-shipped policy at a different
-        // layer; this policy must not duplicate or replace it.
-        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: [AgentFrameworkUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.DoesNotContain("MEAI/", handler.LastUserAgent);
-        Assert.DoesNotContain("foundry-hosting/", handler.LastUserAgent);
-    }
-
-    [Fact]
-    public async Task AgentFrameworkUserAgentPolicy_PreservesExistingUserAgent_WhenAppendingAsync()
-    {
-        // Arrange: a per-call policy upstream that pre-populates the User-Agent header. The AF
-        // policy must read the existing value and append (not overwrite) the agent-framework
-        // segment so both stay reachable on the wire. (The exact separator the HTTP transport
-        // emits between multi-value User-Agent entries is comma per RFC 7230; this test does
-        // not assert on the separator character because that is a transport detail.)
-        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: [new SeedUserAgentPolicy("existing-app/1.0"), AgentFrameworkUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert: both segments survive to the wire.
-        Assert.NotNull(handler.LastUserAgent);
-        Assert.Contains("existing-app/1.0", handler.LastUserAgent);
-        Assert.Contains("agent-framework-dotnet/", handler.LastUserAgent);
-    }
-
-    [Fact]
-    public async Task AgentFrameworkUserAgentPolicy_IsIdempotent_DoesNotDoubleStampAsync()
-    {
-        // Arrange: register the same policy twice on the same pipeline. The second application
-        // must detect the segment is already present and not append it again. Guards against
-        // double-stamping on retries or duplicate registration.
-        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: [AgentFrameworkUserAgentPolicy.Instance, AgentFrameworkUserAgentPolicy.Instance],
-            perTryPolicies: default,
-            beforeTransportPolicies: default);
-
-        // Act
-        var message = pipeline.CreateMessage();
-        message.Request.Method = "POST";
-        message.Request.Uri = new Uri("https://example.test/anything");
-        await pipeline.SendAsync(message);
-
-        // Assert: exactly one occurrence of "agent-framework-dotnet/".
-        Assert.NotNull(handler.LastUserAgent);
-        var ua = handler.LastUserAgent!;
-        var first = ua.IndexOf("agent-framework-dotnet/", StringComparison.Ordinal);
-        Assert.True(first >= 0, "Expected at least one agent-framework-dotnet segment.");
-        var second = ua.IndexOf("agent-framework-dotnet/", first + 1, StringComparison.Ordinal);
-        Assert.Equal(-1, second);
-    }
-
-    [Fact]
-    public void AgentFrameworkUserAgentPolicy_ExposesSingletonInstance()
-    {
-        // Two reads of the static property must return the same instance. The policy is stateless
-        // and shared; allocating a fresh instance per registration site would bloat memory and
-        // defeat the dedup logic in OpenAIRequestPoliciesReflection.AddPolicyIfMissing.
-        var first = AgentFrameworkUserAgentPolicy.Instance;
-        var second = AgentFrameworkUserAgentPolicy.Instance;
-        Assert.Same(first, second);
-    }
-
-    [Fact]
-    public void AgentFrameworkUserAgentPolicy_ValueIncludesAFFoundryAssemblyVersion_ReflectionGuard()
-    {
-        // The policy emits "agent-framework-dotnet/{Microsoft.Agents.AI.Foundry assembly InformationalVersion}".
-        // If the assembly metadata stops being readable, the policy falls back to "agent-framework-dotnet"
-        // without a version, which is a measurable telemetry regression.
-        var attr = typeof(AgentFrameworkUserAgentPolicy).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);
-        }
-    }
-
-    private sealed class SeedUserAgentPolicy : PipelinePolicy
-    {
-        private readonly string _value;
-        public SeedUserAgentPolicy(string value) => this._value = value;
-
-        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-        {
-            message.Request.Headers.Set("User-Agent", this._value);
-            ProcessNext(message, pipeline, currentIndex);
-        }
-
-        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
-        {
-            message.Request.Headers.Set("User-Agent", this._value);
-            return ProcessNextAsync(message, pipeline, currentIndex);
-        }
-    }
-}
@@ -23,9 +23,9 @@ namespace Microsoft.Agents.AI.Foundry.UnitTests;

 #pragma warning disable CS0618
 /// <summary>
-/// Unit tests for the <see cref="AIProjectClientExtensions"/> class.
+/// Unit tests for the <see cref="AzureAIProjectChatClientExtensions"/> class.
 /// </summary>
-public sealed class AIProjectClientExtensionsTests
+public sealed class AzureAIProjectChatClientExtensionsTests
 {
    #region AsAIAgent(AIProjectClient, model, instructions) Tests

@@ -71,11 +71,7 @@ public sealed class AIProjectClientExtensionsTests
        Assert.Equal("test-agent", agent.Name);
        Assert.Equal("A test agent", agent.Description);
        Assert.NotNull(agent.GetService<IChatClient>());
-        // After the FoundryChatClient consolidation the inner chat-client now exposes the
-        // AIProjectClient via GetService — Foundry callers can walk to the project client from
-        // the agent without holding their own reference. (Previously this path returned null
-        // because AsAIAgent(model, instructions) skipped the decorator entirely.)
-        Assert.NotNull(agent.GetService<AIProjectClient>());
+        Assert.Null(agent.GetService<AIProjectClient>());
    }

    /// <summary>
@@ -127,10 +123,7 @@ public sealed class AIProjectClientExtensionsTests
        Assert.NotNull(agent);
        Assert.Equal("options-agent", agent.Name);
        Assert.Equal("Agent from options", agent.Description);
-        // After the FoundryChatClient consolidation the inner chat-client now exposes the
-        // AIProjectClient via GetService — see twin assertion in
-        // AsAIAgent_Rapi_WithModelAndInstructions_CreatesChatClientAgent for the rationale.
-        Assert.NotNull(agent.GetService<AIProjectClient>());
+        Assert.Null(agent.GetService<AIProjectClient>());
    }

    /// <summary>
@@ -192,106 +185,6 @@ public sealed class AIProjectClientExtensionsTests
        Assert.True(userAgentFound, "MEAI user-agent header was not found in any request");
    }

-    /// <summary>
-    /// Verify that the non-versioned AsAIAgent overload now wraps with FoundryChatClient
-    /// (regression-prevention for the previously-untagged extension path).
-    /// </summary>
-    [Fact]
-    public void AsAIAgent_Rapi_WithModelAndInstructions_ExposesFoundryChatClientAndProviderName()
-    {
-        // Arrange
-        AIProjectClient client = this.CreateTestAgentClient();
-
-        // Act
-        ChatClientAgent agent = client.AsAIAgent("gpt-4o-mini", "You are helpful.");
-
-        // Assert: FoundryChatClient is internal-sealed and reachable via GetService<IChatClient>().
-        var chatClient = agent.GetService<IChatClient>();
-        Assert.NotNull(chatClient);
-
-        // Provider tag is "microsoft.foundry" (previously this path had no Foundry tag at all).
-        var metadata = chatClient!.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-        Assert.Equal("gpt-4o-mini", metadata.DefaultModelId);
-
-        // Reaching the FoundryChatClient by type (via InternalsVisibleTo).
-        Assert.NotNull(agent.GetService<FoundryChatClient>());
-    }
-
-    /// <summary>
-    /// Verify that the options-based non-versioned AsAIAgent overload now wraps with FoundryChatClient.
-    /// </summary>
-    [Fact]
-    public void AsAIAgent_Rapi_WithOptions_ExposesFoundryChatClientAndProviderName()
-    {
-        // Arrange
-        AIProjectClient client = this.CreateTestAgentClient();
-        ChatClientAgentOptions options = new()
-        {
-            Name = "options-agent",
-            ChatOptions = new ChatOptions { ModelId = "gpt-4o-mini", Instructions = "x" },
-        };
-
-        // Act
-        ChatClientAgent agent = client.AsAIAgent(options);
-
-        // Assert
-        var chatClient = agent.GetService<IChatClient>();
-        Assert.NotNull(chatClient);
-        var metadata = chatClient!.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-        Assert.NotNull(agent.GetService<FoundryChatClient>());
-    }
-
-    /// <summary>
-    /// Verify that the non-versioned AsAIAgent overload stamps the
-    /// agent-framework-dotnet/{version} segment on outbound requests via the new
-    /// AgentFrameworkUserAgentPolicy registered by FoundryChatClient.
-    /// </summary>
-    [Fact]
-    public async Task AsAIAgent_Rapi_WithModelAndInstructions_StampsAgentFrameworkUserAgentSegmentAsync()
-    {
-        bool afSeen = false;
-        using HttpHandlerAssert httpHandler = new(request =>
-        {
-            if (request.Headers.TryGetValues("User-Agent", out IEnumerable<string>? values))
-            {
-                foreach (string value in values)
-                {
-                    if (value.Contains("agent-framework-dotnet/"))
-                    {
-                        afSeen = true;
-                    }
-                }
-            }
-
-            return new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json")
-            };
-        });
-
-#pragma warning disable CA5399
-        using HttpClient httpClient = new(httpHandler);
-#pragma warning restore CA5399
-
-        AIProjectClient aiProjectClient = new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new() { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        ChatClientAgent agent = aiProjectClient.AsAIAgent("gpt-4o-mini", "You are helpful.");
-
-        // Act
-        AgentSession session = await agent.CreateSessionAsync();
-        await agent.RunAsync("Hello", session);
-
-        // Assert
-        Assert.True(afSeen, "Expected agent-framework-dotnet/{version} segment on outbound requests from AsAIAgent(model, instructions).");
-    }
-
    #endregion

    #region AsAIAgent(AIProjectClient, ProjectsAgentRecord) Tests
@@ -0,0 +1,209 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel.Primitives;
+using System.Net;
+using System.Net.Http;
+using System.Text;
+using System.Threading.Tasks;
+using Azure.AI.Extensions.OpenAI;
+using Azure.AI.Projects;
+
+namespace Microsoft.Agents.AI.Foundry.UnitTests;
+
+#pragma warning disable CS0618
+public class AzureAIProjectChatClientTests
+{
+    /// <summary>
+    /// Verify that after the first RunAsync, the session's ConversationId is set from the
+    /// response, and subsequent requests include that conversation ID automatically.
+    /// </summary>
+    [Fact]
+    public async Task ChatClient_UsesDefaultConversationIdAsync()
+    {
+        // Arrange
+        var responsesRequestCount = 0;
+        using var httpHandler = new HttpHandlerAssert(async (request) =>
+        {
+            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
+            {
+                responsesRequestCount++;
+
+                // Assert: On the second Responses API call, verify the conversation ID
+                // from the first response is automatically included in the request body.
+                if (responsesRequestCount == 2 && request.Content is not null)
+                {
+                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+                    Assert.Contains("resp_0888a", requestBody);
+                }
+
+                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
+            }
+
+            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+
+        AIProjectClient projectClient = new(
+            new Uri("https://test.openai.azure.com/"),
+            new FakeAuthenticationTokenProvider(),
+            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
+
+        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
+
+        // Act
+        var session = await agent.CreateSessionAsync();
+        await agent.RunAsync("Hello", session);
+        await agent.RunAsync("Follow up", session);
+
+        // Assert
+        Assert.Equal(2, responsesRequestCount);
+        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
+        Assert.Equal("resp_0888a46cbf2b1ff3006914596e05d08195a77c3f5187b769a7", chatClientSession.ConversationId);
+    }
+
+    /// <summary>
+    /// Verify that when the chat client doesn't have a default "conv_" conversation id, the chat client still uses the conversation ID in HTTP requests.
+    /// </summary>
+    [Fact]
+    public async Task ChatClient_UsesPerRequestConversationId_WhenNoDefaultConversationIdIsProvidedAsync()
+    {
+        // Arrange
+        var requestTriggered = false;
+        using var httpHandler = new HttpHandlerAssert(async (request) =>
+        {
+            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
+            {
+                requestTriggered = true;
+
+                // Assert
+                if (request.Content is not null)
+                {
+                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+                    Assert.Contains("conv_12345", requestBody);
+                }
+
+                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
+            }
+
+            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+
+        AIProjectClient projectClient = new(
+            new Uri("https://test.openai.azure.com/"),
+            new FakeAuthenticationTokenProvider(),
+            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
+
+        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
+
+        // Act
+        var session = await agent.CreateSessionAsync();
+        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "conv_12345" } });
+
+        Assert.True(requestTriggered);
+        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
+        Assert.Equal("conv_12345", chatClientSession.ConversationId);
+    }
+
+    /// <summary>
+    /// Verify that even when the chat client has a default conversation id, the chat client will prioritize the per-request conversation id provided in HTTP requests.
+    /// </summary>
+    [Fact]
+    public async Task ChatClient_UsesPerRequestConversationId_EvenWhenDefaultConversationIdIsProvidedAsync()
+    {
+        // Arrange
+        var requestTriggered = false;
+        using var httpHandler = new HttpHandlerAssert(async (request) =>
+        {
+            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
+            {
+                requestTriggered = true;
+
+                // Assert
+                if (request.Content is not null)
+                {
+                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+                    Assert.Contains("conv_12345", requestBody);
+                }
+
+                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
+            }
+
+            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+
+        AIProjectClient projectClient = new(
+            new Uri("https://test.openai.azure.com/"),
+            new FakeAuthenticationTokenProvider(),
+            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
+
+        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
+
+        // Act
+        var session = await agent.CreateSessionAsync();
+        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "conv_12345" } });
+
+        Assert.True(requestTriggered);
+        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
+        Assert.Equal("conv_12345", chatClientSession.ConversationId);
+    }
+
+    /// <summary>
+    /// Verify that when the chat client is provided without a "conv_" prefixed conversation ID, the chat client uses the previous conversation ID in HTTP requests.
+    /// </summary>
+    [Fact]
+    public async Task ChatClient_UsesPreviousResponseId_WhenConversationIsNotPrefixedAsConvAsync()
+    {
+        // Arrange
+        var requestTriggered = false;
+        using var httpHandler = new HttpHandlerAssert(async (request) =>
+        {
+            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
+            {
+                requestTriggered = true;
+
+                // Assert
+                if (request.Content is not null)
+                {
+                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+                    Assert.Contains("resp_0888a", requestBody);
+                }
+
+                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
+            }
+
+            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
+        });
+
+#pragma warning disable CA5399
+        using var httpClient = new HttpClient(httpHandler);
+#pragma warning restore CA5399
+
+        AIProjectClient projectClient = new(
+            new Uri("https://test.openai.azure.com/"),
+            new FakeAuthenticationTokenProvider(),
+            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
+
+        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
+
+        // Act
+        var session = await agent.CreateSessionAsync();
+        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "resp_0888a" } });
+
+        Assert.True(requestTriggered);
+        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
+        Assert.Equal("resp_0888a46cbf2b1ff3006914596e05d08195a77c3f5187b769a7", chatClientSession.ConversationId);
+    }
+}
+#pragma warning restore CS0618
@@ -1,200 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.ClientModel.Primitives;
-using System.Net;
-using System.Net.Http;
-using System.Text;
-using System.Threading.Tasks;
-using Azure.AI.Projects;
-using OpenAI.Files;
-
-#pragma warning disable OPENAI001, CS0618
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for the file and vector-store forwarder extensions on <see cref="FoundryAgent"/>
-/// declared in <see cref="FoundryAgentExtensions"/>. The forwarders are thin shims over the
-/// inner <see cref="FoundryChatClient"/>, so coverage focuses on (a) request shape (the agent
-/// path reaches the same wire as a direct chat-client call), (b) null/missing-FoundryChatClient
-/// handling, and (c) returns the same payload the chat client would.
-/// </summary>
-public sealed class FoundryAgentExtensionsTests
-{
-    private static readonly Uri s_testProjectEndpoint = new("https://test.openai.azure.com/");
-
-    [Fact]
-    public async Task UploadFileAsync_Forwards_ToInnerFoundryChatClient_Async()
-    {
-        // Arrange — agent built via the Responses Agent (Mode 1) projectEndpoint+model+instructions
-        // ctor wires a FoundryChatClient inside that the extension can resolve via GetService.
-        var sawPostToFiles = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Post && req.RequestUri!.AbsolutePath.Contains("/files", StringComparison.Ordinal))
-            {
-                sawPostToFiles = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(FakeFileJson("file_via_agent"), Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var agent = new FoundryAgent(
-            projectEndpoint: s_testProjectEndpoint,
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "Be helpful.",
-            clientOptions: new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var path = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"fae-{Guid.NewGuid():N}.txt");
-        System.IO.File.WriteAllText(path, "hello");
-
-        try
-        {
-            // Act — call the forwarder on the agent.
-            var result = await agent.UploadFileAsync(path, FileUploadPurpose.Assistants);
-
-            // Assert
-            Assert.True(sawPostToFiles, "POST to /files must reach the wire through the agent forwarder.");
-            Assert.Equal("file_via_agent", result.Id);
-        }
-        finally
-        {
-            System.IO.File.Delete(path);
-        }
-    }
-
-    [Fact]
-    public async Task DeleteFileAsync_Forwards_ToInnerFoundryChatClient_Async()
-    {
-        var sawDelete = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Delete && req.RequestUri!.AbsolutePath.Contains("/files/", StringComparison.Ordinal))
-            {
-                sawDelete = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent("{\"id\":\"file_abc\",\"object\":\"file\",\"deleted\":true}", Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var agent = new FoundryAgent(
-            projectEndpoint: s_testProjectEndpoint,
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "Be helpful.",
-            clientOptions: new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var result = await agent.DeleteFileAsync("file_abc");
-
-        Assert.True(sawDelete);
-        Assert.NotNull(result);
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_Forwards_ToInnerFoundryChatClient_Async()
-    {
-        var sawVectorStorePost = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Post && req.RequestUri!.AbsolutePath.Contains("/vector_stores", StringComparison.Ordinal))
-            {
-                sawVectorStorePost = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(FakeVectorStoreJson("vs_via_agent", "kb"), Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var agent = new FoundryAgent(
-            projectEndpoint: s_testProjectEndpoint,
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "Be helpful.",
-            clientOptions: new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var store = await agent.CreateVectorStoreAsync("kb", Array.Empty<string>());
-
-        Assert.True(sawVectorStorePost);
-        Assert.Equal("vs_via_agent", store.Id);
-    }
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_Forwards_ToInnerFoundryChatClient_Async()
-    {
-        var sawDelete = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Delete && req.RequestUri!.AbsolutePath.Contains("/vector_stores/", StringComparison.Ordinal))
-            {
-                sawDelete = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent("{\"id\":\"vs_abc\",\"object\":\"vector_store.deleted\",\"deleted\":true}", Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var agent = new FoundryAgent(
-            projectEndpoint: s_testProjectEndpoint,
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "Be helpful.",
-            clientOptions: new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        await agent.DeleteVectorStoreAsync("vs_abc");
-
-        Assert.True(sawDelete);
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_NullAgent_ThrowsArgumentNullExceptionAsync()
-        => await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            FoundryAgentExtensions.UploadFileAsync(null!, "x", FileUploadPurpose.Assistants));
-
-    [Fact]
-    public async Task DeleteFileAsync_NullAgent_ThrowsArgumentNullExceptionAsync()
-        => await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            FoundryAgentExtensions.DeleteFileAsync(null!, "file_abc"));
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_NullAgent_ThrowsArgumentNullExceptionAsync()
-        => await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            FoundryAgentExtensions.CreateVectorStoreAsync(null!, "kb", Array.Empty<string>()));
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_NullAgent_ThrowsArgumentNullExceptionAsync()
-        => await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            FoundryAgentExtensions.DeleteVectorStoreAsync(null!, "vs_abc"));
-
-    // ----- Helpers -----
-
-    private static string FakeFileJson(string id)
-        => $"{{\"id\":\"{id}\",\"object\":\"file\",\"bytes\":11,\"created_at\":1700000000,\"filename\":\"x.txt\",\"purpose\":\"assistants\",\"status\":\"processed\"}}";
-
-    private static string FakeVectorStoreJson(string id, string name)
-        => $"{{\"id\":\"{id}\",\"object\":\"vector_store\",\"created_at\":1700000000,\"name\":\"{name}\",\"usage_bytes\":0,\"file_counts\":{{\"in_progress\":0,\"completed\":0,\"failed\":0,\"cancelled\":0,\"total\":0}},\"status\":\"completed\",\"last_active_at\":1700000000}}";
-}
-#pragma warning restore CS0618
@@ -2,6 +2,7 @@

 using System;
 using System.ClientModel.Primitives;
+using System.Collections.Generic;
 using System.Net;
 using System.Net.Http;
 using System.Text;
@@ -351,24 +352,18 @@ public class FoundryAgentTests
    }

    [Fact]
-    public async Task Constructor_AgentFrameworkUserAgentHeaderAddedToRequestsAsync()
+    public async Task Constructor_UserAgentHeaderAddedToRequestsAsync()
    {
-        // After the FoundryChatClient consolidation, every outbound request from a
-        // FoundryAgent-built chat client carries the new agent-framework-dotnet/{version}
-        // segment (stamped by AgentFrameworkUserAgentPolicy registered via the MEAI
-        // OpenAIRequestPolicies hook). The local MEAI/{version} stamp was removed because
-        // MEAI 10.5.1 stamps that itself; this test only verifies the framework-wide segment
-        // that the Foundry package now guarantees.
-        bool agentFrameworkUserAgentFound = false;
+        bool userAgentFound = false;
        using HttpHandlerAssert httpHandler = new(request =>
        {
-            if (request.Headers.TryGetValues("User-Agent", out System.Collections.Generic.IEnumerable<string>? values))
+            if (request.Headers.TryGetValues("User-Agent", out IEnumerable<string>? values))
            {
                foreach (string value in values)
                {
-                    if (value.Contains("agent-framework-dotnet/"))
+                    if (value.StartsWith("MEAI/", StringComparison.OrdinalIgnoreCase))
                    {
-                        agentFrameworkUserAgentFound = true;
+                        userAgentFound = true;
                    }
                }
            }
@@ -401,7 +396,7 @@ public class FoundryAgentTests
        AgentSession session = await agent.CreateSessionAsync();
        await agent.RunAsync("Hello", session);

-        Assert.True(agentFrameworkUserAgentFound, "Expected agent-framework-dotnet user-agent segment to be present on outbound requests.");
+        Assert.True(userAgentFound, "Expected MEAI user-agent header to be present in requests.");
    }

    #endregion
@@ -439,9 +434,6 @@ public class FoundryAgentTests
    [Fact]
    public void AgentEndpointConstructor_GetServiceProjectOpenAIClient_ReturnsNull()
    {
-        // Behavior change: FoundryAgent no longer caches a ProjectOpenAIClient. Callers
-        // retrieve it from the AIProjectClient themselves
-        // (agent.GetService<AIProjectClient>()!.GetProjectOpenAIClient()).
        FoundryAgent agent = new(s_testAgentEndpoint, new FakeAuthenticationTokenProvider());

        Assert.Null(agent.GetService<ProjectOpenAIClient>());
@@ -450,10 +442,6 @@ public class FoundryAgentTests
    [Fact]
    public void AgentEndpointConstructor_GetServiceAIProjectClient_ReturnsNonNull()
    {
-        // Behavior change: after Plan #2's Agent Endpoint mode (Mode 3) AIProjectClient materialization, the
-        // agent-endpoint constructor now derives a project-level AIProjectClient from the
-        // parsed project root URL and surfaces it via GetService. Previously this returned
-        // null because no AIProjectClient was constructed for hosted-agent-endpoint agents.
        FoundryAgent agent = new(s_testAgentEndpoint, new FakeAuthenticationTokenProvider());

        Assert.NotNull(agent.GetService<AIProjectClient>());
@@ -462,7 +450,6 @@ public class FoundryAgentTests
    [Fact]
    public void ProjectEndpointConstructor_GetServiceProjectOpenAIClient_ReturnsNull()
    {
-        // See AgentEndpointConstructor_GetServiceProjectOpenAIClient_ReturnsNull for rationale.
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
@@ -624,57 +611,6 @@ public class FoundryAgentTests
        Assert.True(meaiSeen, "Expected MEAI/x.y.z to appear in the User-Agent header on the agent-endpoint pipeline.");
    }

-    [Fact]
-    public void AgentEndpointConstructor_ExposesFoundryProviderName_OnChatClientMetadata()
-    {
-        // Behavior change: after the FoundryChatClient consolidation, the agent-endpoint path
-        // now wraps with FoundryChatClient in the Agent Endpoint mode (Mode 3) and stamps the microsoft.foundry provider
-        // name. Previously this path used a bare AsIChatClient() with no Foundry-specific
-        // decorator, so the provider name defaulted to whatever MEAI surfaces. This guards the
-        // new behavior.
-        FoundryAgent agent = new(s_testAgentEndpoint, new FakeAuthenticationTokenProvider());
-
-        var metadata = agent.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-    }
-
-    [Fact]
-    public async Task AgentEndpointConstructor_StampsAgentFrameworkUserAgentSegmentAsync()
-    {
-        // Behavior change: after the FoundryChatClient consolidation, every outbound request
-        // from the agent-endpoint constructor carries the agent-framework-dotnet/{version}
-        // segment via AgentFrameworkUserAgentPolicy. Previously this path had no
-        // agent-framework branding at all.
-        bool afSeen = false;
-        using HttpHandlerAssert handler = new(req =>
-        {
-            if (req.Headers.TryGetValues("User-Agent", out var values))
-            {
-                foreach (string v in values)
-                {
-                    if (v.Contains("agent-framework-dotnet/"))
-                    {
-                        afSeen = true;
-                    }
-                }
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json"),
-            };
-        });
-#pragma warning disable CA5399
-        using HttpClient http = new(handler);
-#pragma warning restore CA5399
-        ProjectOpenAIClientOptions opts = new() { Transport = new HttpClientPipelineTransport(http) };
-
-        FoundryAgent agent = new(s_testAgentEndpoint, new FakeAuthenticationTokenProvider(), clientOptions: opts);
-        await agent.RunAsync("Hello");
-
-        Assert.True(afSeen, "Expected agent-framework-dotnet/{version} segment on the agent-endpoint outbound User-Agent.");
-    }
-
    [Fact]
    public async Task AgentEndpointConstructor_PassesThroughCallerPolicyOnPerAgentPipelineAsync()
    {
@@ -730,22 +666,82 @@ public class FoundryAgentTests
    }

    [Fact]
-    public void AgentEndpointConstructor_PropagatesUserAgentApplicationId_ToProjectLevelClient()
+    public void AgentEndpointConstructor_PreservesUserAgentApplicationId()
    {
-        // The MEAI policy adds its own User-Agent header so we cannot reliably observe the OpenAI SDK's
-        // application-id stamp in the outbound request. Verify the value is propagated onto the
-        // caller's options bag and that the materialized AIProjectClient is reachable so
-        // downstream conversation/file/vector-store operations can pick the application id up.
        ProjectOpenAIClientOptions opts = new() { UserAgentApplicationId = "my-app-id" };

        FoundryAgent agent = new(s_testAgentEndpoint, new FakeAuthenticationTokenProvider(), clientOptions: opts);

-        AIProjectClient? aiProjectClient = agent.GetService<AIProjectClient>();
-        Assert.NotNull(aiProjectClient);
        // Caller's UserAgentApplicationId is preserved on the per-agent options bag verbatim.
+        Assert.NotNull(agent);
        Assert.Equal("my-app-id", opts.UserAgentApplicationId);
    }

+    [Fact]
+    public void CreateProjectClientOptions_NullCallerOptions_ReturnsNull()
+    {
+        Assert.Null(FoundryAgent.CreateProjectClientOptions(null));
+    }
+
+    [Fact]
+    public void CreateProjectClientOptions_CarriesPipelineSettingsAndUserAgent()
+    {
+        // Arrange
+        var transport = new FakePipelineTransport();
+        var retryPolicy = new FakeRetryPolicy();
+        var messageLoggingPolicy = new FakeMessageLoggingPolicy();
+        var clientLoggingOptions = new ClientLoggingOptions { EnableLogging = false };
+        var networkTimeout = TimeSpan.FromSeconds(42);
+
+        ProjectOpenAIClientOptions callerOptions = new()
+        {
+            UserAgentApplicationId = "my-app-id",
+            Transport = transport,
+            RetryPolicy = retryPolicy,
+            MessageLoggingPolicy = messageLoggingPolicy,
+            ClientLoggingOptions = clientLoggingOptions,
+            NetworkTimeout = networkTimeout,
+        };
+
+        // Act
+        AIProjectClientOptions? projectOptions = FoundryAgent.CreateProjectClientOptions(callerOptions);
+
+        // Assert: every settable pipeline behavior the caller configured is forwarded
+        // onto the project-level options bag, not silently dropped.
+        Assert.NotNull(projectOptions);
+        Assert.Equal("my-app-id", projectOptions!.UserAgentApplicationId);
+        Assert.Same(transport, projectOptions.Transport);
+        Assert.Same(retryPolicy, projectOptions.RetryPolicy);
+        Assert.Same(messageLoggingPolicy, projectOptions.MessageLoggingPolicy);
+        Assert.Same(clientLoggingOptions, projectOptions.ClientLoggingOptions);
+        Assert.Equal(networkTimeout, projectOptions.NetworkTimeout);
+    }
+
+    private sealed class FakeRetryPolicy : PipelinePolicy
+    {
+        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+            => ProcessNext(message, pipeline, currentIndex);
+
+        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+            => ProcessNextAsync(message, pipeline, currentIndex);
+    }
+
+    private sealed class FakeMessageLoggingPolicy : PipelinePolicy
+    {
+        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+            => ProcessNext(message, pipeline, currentIndex);
+
+        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+            => ProcessNextAsync(message, pipeline, currentIndex);
+    }
+
+    private sealed class FakePipelineTransport : PipelineTransport
+    {
+        protected override PipelineMessage CreateMessageCore() => throw new NotSupportedException();
+        protected override void ProcessCore(PipelineMessage message) => throw new NotSupportedException();
+        protected override ValueTask ProcessCoreAsync(PipelineMessage message) => throw new NotSupportedException();
+    }
+
    #endregion

    #region ParseAgentEndpoint tests
@@ -828,13 +824,13 @@ public class FoundryAgentTests
        private readonly string _value;
        public HeaderStampPolicy(string name, string value) { this._name = name; this._value = value; }

-        public override void Process(PipelineMessage message, System.Collections.Generic.IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        public override void Process(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
        {
            message.Request.Headers.Set(this._name, this._value);
            ProcessNext(message, pipeline, currentIndex);
        }

-        public override ValueTask ProcessAsync(PipelineMessage message, System.Collections.Generic.IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
+        public override ValueTask ProcessAsync(PipelineMessage message, IReadOnlyList<PipelinePolicy> pipeline, int currentIndex)
        {
            message.Request.Headers.Set(this._name, this._value);
            return ProcessNextAsync(message, pipeline, currentIndex);
@@ -1,616 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.ClientModel.Primitives;
-using System.Net;
-using System.Net.Http;
-using System.Reflection;
-using System.Text;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-
-#pragma warning disable OPENAI001, CS0618
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for the internal <see cref="FoundryChatClient"/>. Covers the three construction
-/// modes (Responses Agent, Prompt Agent, Agent Endpoint), the GetService
-/// returns per mode, the metadata-tagging contract, the agent-framework user-agent registration,
-/// the Agent Endpoint mode (Mode 3) URL parsing happy and error paths, and end-to-end behavior through the public
-/// <c>AsAIAgent(AgentReference)</c> extension that constructs a FoundryChatClient internally.
-/// </summary>
-public sealed class FoundryChatClientTests
-{
-    #region the Responses Agent mode (Mode 1): Responses Agent (AIProjectClient + modelId)
-
-    [Fact]
-    public void Mode1_ResponsesAgent_StampsFoundryProviderName()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        // Assert
-        var metadata = chatClient.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-        Assert.Equal("gpt-4o-mini", metadata.DefaultModelId);
-    }
-
-    [Fact]
-    public void Mode1_ResponsesAgent_ExposesAIProjectClient_ViaGetService()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        // Assert
-        Assert.Same(projectClient, chatClient.GetService<AIProjectClient>());
-        // ProjectOpenAIClient is intentionally NOT exposed via GetService — callers retrieve
-        // it from the AIProjectClient themselves (aiProjectClient.GetProjectOpenAIClient()).
-        Assert.Null(chatClient.GetService<ProjectOpenAIClient>());
-    }
-
-    [Fact]
-    public void Mode1_ResponsesAgent_ReturnsNullForAgentSpecificServices()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        // Assert
-        Assert.Null(chatClient.GetService<AgentReference>());
-        Assert.Null(chatClient.GetService<ProjectsAgentVersion>());
-        Assert.Null(chatClient.GetService<ProjectsAgentRecord>());
-        // No agent name exists in the Responses Agent mode (Mode 1) — only the Prompt Agent mode (Mode 2) (from AgentReference.Name) and the Agent Endpoint mode (Mode 3)
-        // (parsed from URL) populate FoundryChatClient.AgentName.
-        Assert.Null(chatClient.AgentName);
-    }
-
-    [Fact]
-    public void Mode1_ResponsesAgent_ThrowsOnNullProjectClient()
-        => Assert.Throws<ArgumentNullException>(() => new FoundryChatClient(aiProjectClient: null!, "gpt-4o-mini"));
-
-    [Fact]
-    public void Mode1_ResponsesAgent_ThrowsOnEmptyModelId()
-        => Assert.Throws<ArgumentException>(() => new FoundryChatClient(CreateProjectClient(), modelId: ""));
-
-    #endregion
-
-    #region the Prompt Agent mode (Mode 2): Prompt Agent (direct unit tests)
-
-    [Fact]
-    public void Mode2_PromptAgent_StampsFoundryProviderNameAndDefaultModelId()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-        var agentRef = new AgentReference("agent-name", "1");
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, agentRef, defaultModelId: "gpt-4o", baseChatOptions: null);
-
-        // Assert
-        var metadata = chatClient.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-        Assert.Equal("gpt-4o", metadata.DefaultModelId);
-    }
-
-    [Fact]
-    public void Mode2_PromptAgent_ExposesAgentReference_ViaGetService()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-        var agentRef = new AgentReference("agent-name", "1");
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, agentRef, defaultModelId: null, baseChatOptions: null);
-
-        // Assert
-        Assert.Same(agentRef, chatClient.GetService<AgentReference>());
-        Assert.Same(projectClient, chatClient.GetService<AIProjectClient>());
-        // ProjectOpenAIClient is intentionally NOT exposed via GetService — see comment in
-        // Mode1_ResponsesAgent_ExposesAIProjectClient_ViaGetService.
-        Assert.Null(chatClient.GetService<ProjectOpenAIClient>());
-        // Version/Record were not provided via this ctor.
-        Assert.Null(chatClient.GetService<ProjectsAgentVersion>());
-        Assert.Null(chatClient.GetService<ProjectsAgentRecord>());
-    }
-
-    [Fact]
-    public void Mode2_PromptAgent_PopulatesAgentNameFromAgentReference()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-        var agentRef = new AgentReference("my-server-side-agent", "1");
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, agentRef, defaultModelId: null, baseChatOptions: null);
-
-        // Assert: AgentName is general-purpose across the Prompt Agent (Mode 2) and Agent Endpoint (Mode 3) modes. In the Prompt Agent mode (Mode 2) it mirrors
-        // AgentReference.Name so callers have a uniform handle regardless of construction mode.
-        Assert.Equal("my-server-side-agent", chatClient.AgentName);
-    }
-
-    [Fact]
-    public void Mode2_PromptAgent_AllowsNullDefaultModelIdAndBaseChatOptions()
-    {
-        // Arrange
-        var projectClient = CreateProjectClient();
-        var agentRef = new AgentReference("agent-name", "1");
-
-        // Act + Assert: must not throw; defaultModelId and baseChatOptions are optional.
-        var chatClient = new FoundryChatClient(projectClient, agentRef, defaultModelId: null, baseChatOptions: null);
-        Assert.NotNull(chatClient);
-    }
-
-    [Fact]
-    public void Mode2_PromptAgent_ThrowsOnNullAgentReference()
-        => Assert.Throws<ArgumentNullException>(() =>
-            new FoundryChatClient(CreateProjectClient(), agentReference: null!, defaultModelId: null, baseChatOptions: null));
-
-    #endregion
-
-    #region the Prompt Agent mode (Mode 2): Prompt Agent end-to-end round-trip via AsAIAgent(AgentReference) extension
-
-    // The end-to-end tests below exercise the same FoundryChatClient mode-2 behaviors above,
-    // but through the public AsAIAgent(AgentReference) extension that constructs a FoundryChatClient
-    // internally. They focus on the conversation-id handling that only manifests through the
-    // ChatClientAgentSession surface, which requires a fully assembled agent rather than a bare
-    // chat client.
-
-    /// <summary>
-    /// Verify that after the first RunAsync, the session's ConversationId is set from the
-    /// response, and subsequent requests include that conversation ID automatically.
-    /// </summary>
-    [Fact]
-    public async Task EndToEnd_AgentReference_UsesDefaultConversationIdAsync()
-    {
-        // Arrange
-        var responsesRequestCount = 0;
-        using var httpHandler = new HttpHandlerAssert(async (request) =>
-        {
-            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
-            {
-                responsesRequestCount++;
-
-                // Assert: On the second Responses API call, verify the conversation ID
-                // from the first response is automatically included in the request body.
-                if (responsesRequestCount == 2 && request.Content is not null)
-                {
-                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
-                    Assert.Contains("resp_0888a", requestBody);
-                }
-
-                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
-            }
-
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(httpHandler);
-#pragma warning restore CA5399
-
-        AIProjectClient projectClient = new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
-
-        // Act
-        var session = await agent.CreateSessionAsync();
-        await agent.RunAsync("Hello", session);
-        await agent.RunAsync("Follow up", session);
-
-        // Assert
-        Assert.Equal(2, responsesRequestCount);
-        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
-        Assert.Equal("resp_0888a46cbf2b1ff3006914596e05d08195a77c3f5187b769a7", chatClientSession.ConversationId);
-    }
-
-    /// <summary>
-    /// Verify that when the chat client doesn't have a default "conv_" conversation id, the chat client still uses the conversation ID in HTTP requests.
-    /// </summary>
-    [Fact]
-    public async Task EndToEnd_AgentReference_UsesPerRequestConversationId_WhenNoDefaultConversationIdIsProvidedAsync()
-    {
-        // Arrange
-        var requestTriggered = false;
-        using var httpHandler = new HttpHandlerAssert(async (request) =>
-        {
-            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
-            {
-                requestTriggered = true;
-
-                // Assert
-                if (request.Content is not null)
-                {
-                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
-                    Assert.Contains("conv_12345", requestBody);
-                }
-
-                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
-            }
-
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(httpHandler);
-#pragma warning restore CA5399
-
-        AIProjectClient projectClient = new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
-
-        // Act
-        var session = await agent.CreateSessionAsync();
-        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "conv_12345" } });
-
-        Assert.True(requestTriggered);
-        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
-        Assert.Equal("conv_12345", chatClientSession.ConversationId);
-    }
-
-    /// <summary>
-    /// Verify that even when the chat client has a default conversation id, the chat client will prioritize the per-request conversation id provided in HTTP requests.
-    /// </summary>
-    [Fact]
-    public async Task EndToEnd_AgentReference_UsesPerRequestConversationId_EvenWhenDefaultConversationIdIsProvidedAsync()
-    {
-        // Arrange
-        var requestTriggered = false;
-        using var httpHandler = new HttpHandlerAssert(async (request) =>
-        {
-            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
-            {
-                requestTriggered = true;
-
-                // Assert
-                if (request.Content is not null)
-                {
-                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
-                    Assert.Contains("conv_12345", requestBody);
-                }
-
-                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
-            }
-
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(httpHandler);
-#pragma warning restore CA5399
-
-        AIProjectClient projectClient = new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
-
-        // Act
-        var session = await agent.CreateSessionAsync();
-        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "conv_12345" } });
-
-        Assert.True(requestTriggered);
-        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
-        Assert.Equal("conv_12345", chatClientSession.ConversationId);
-    }
-
-    /// <summary>
-    /// Verify that when the chat client is provided without a "conv_" prefixed conversation ID, the chat client uses the previous conversation ID in HTTP requests.
-    /// </summary>
-    [Fact]
-    public async Task EndToEnd_AgentReference_UsesPreviousResponseId_WhenConversationIsNotPrefixedAsConvAsync()
-    {
-        // Arrange
-        var requestTriggered = false;
-        using var httpHandler = new HttpHandlerAssert(async (request) =>
-        {
-            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
-            {
-                requestTriggered = true;
-
-                // Assert
-                if (request.Content is not null)
-                {
-                    var requestBody = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
-                    Assert.Contains("resp_0888a", requestBody);
-                }
-
-                return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetOpenAIDefaultResponseJson(), Encoding.UTF8, "application/json") };
-            }
-
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent(TestDataUtil.GetAgentResponseJson(), Encoding.UTF8, "application/json") };
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(httpHandler);
-#pragma warning restore CA5399
-
-        AIProjectClient projectClient = new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions() { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var agent = projectClient.AsAIAgent(new AgentReference("agent-name"));
-
-        // Act
-        var session = await agent.CreateSessionAsync();
-        await agent.RunAsync("Hello", session, options: new ChatClientAgentRunOptions() { ChatOptions = new() { ConversationId = "resp_0888a" } });
-
-        Assert.True(requestTriggered);
-        var chatClientSession = Assert.IsType<ChatClientAgentSession>(session);
-        Assert.Equal("resp_0888a46cbf2b1ff3006914596e05d08195a77c3f5187b769a7", chatClientSession.ConversationId);
-    }
-
-    #endregion
-
-    #region the Agent Endpoint mode (Mode 3): Agent Endpoint
-
-    [Fact]
-    public void Mode3_AgentEndpoint_ParsesAgentNameFromUrl()
-    {
-        // Arrange + Act
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: null);
-
-        // Assert
-        Assert.Equal("myagent", chatClient.AgentName);
-    }
-
-    [Fact]
-    public void Mode3_AgentEndpoint_StampsFoundryProviderName()
-    {
-        // Act
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: null);
-
-        // Assert
-        var metadata = chatClient.GetService<ChatClientMetadata>();
-        Assert.NotNull(metadata);
-        Assert.Equal("microsoft.foundry", metadata!.ProviderName);
-        // No model id is knowable from the URL alone.
-        Assert.Null(metadata.DefaultModelId);
-    }
-
-    [Fact]
-    public void Mode3_AgentEndpoint_ExposesProjectOpenAIClientAndAIProjectClient()
-    {
-        // Act
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: null);
-
-        // Assert
-        // ProjectOpenAIClient is intentionally NOT exposed via GetService — callers retrieve
-        // it from the AIProjectClient themselves (aiProjectClient.GetProjectOpenAIClient()).
-        Assert.Null(chatClient.GetService<ProjectOpenAIClient>());
-        // After the materialization change, the Agent Endpoint mode (Mode 3) also exposes a working AIProjectClient
-        // built from the parsed project root. This makes the helper surface symmetric across
-        // all three construction modes.
-        Assert.NotNull(chatClient.GetService<AIProjectClient>());
-        Assert.Null(chatClient.GetService<AgentReference>());
-        Assert.Null(chatClient.GetService<ProjectsAgentVersion>());
-        Assert.Null(chatClient.GetService<ProjectsAgentRecord>());
-    }
-
-    [Fact]
-    public void Mode3_AgentEndpoint_MaterializedAIProjectClient_TargetsParsedProjectRoot()
-    {
-        // The Agent Endpoint mode (Mode 3) ctor must derive the project root from the agent endpoint URL and
-        // construct the AIProjectClient against that root, NOT the agent endpoint itself.
-        var agentEndpoint = new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai");
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: agentEndpoint,
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: null);
-
-        var aiProjectClient = chatClient.GetService<AIProjectClient>();
-        Assert.NotNull(aiProjectClient);
-        // AIProjectClient does not expose its endpoint publicly, so we rely on reflection on
-        // the well-known private field. If the SDK field shape changes this guard fails loudly.
-        var field = typeof(AIProjectClient).GetField("_endpoint", BindingFlags.Instance | BindingFlags.NonPublic);
-        Assert.NotNull(field);
-        var actualEndpoint = (Uri)field!.GetValue(aiProjectClient!)!;
-        Assert.Equal("https://example.com/api/projects/myproj", actualEndpoint.AbsoluteUri.TrimEnd('/'));
-    }
-
-    [Fact]
-    public void Mode3_AgentEndpoint_MaterializedAIProjectClient_IsReusedAcrossGetServiceCalls()
-    {
-        // Repeated GetService<AIProjectClient>() calls must return the same instance — the
-        // materialized client is cached in the existing _aiProjectClient field, not built on
-        // demand each call.
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: null);
-
-        var first = chatClient.GetService<AIProjectClient>();
-        var second = chatClient.GetService<AIProjectClient>();
-        Assert.NotNull(first);
-        Assert.Same(first, second);
-    }
-
-    [Fact]
-    public void Mode1_ResponsesAgent_AIProjectClient_IsTheSuppliedInstance()
-    {
-        // Regression check: the Responses Agent mode (Mode 1) must continue to expose the AIProjectClient the caller
-        // supplied via the constructor, NOT a freshly-materialized one.
-        var supplied = CreateProjectClient();
-        var chatClient = new FoundryChatClient(supplied, "gpt-4o-mini");
-        Assert.Same(supplied, chatClient.GetService<AIProjectClient>());
-    }
-
-    [Fact]
-    public void Mode2_PromptAgent_AIProjectClient_IsTheSuppliedInstance()
-    {
-        // Regression check: the Prompt Agent mode (Mode 2) must continue to expose the AIProjectClient the caller
-        // supplied via the constructor.
-        var supplied = CreateProjectClient();
-        var agentRef = new AgentReference("agent-name", "1");
-        var chatClient = new FoundryChatClient(supplied, agentRef, defaultModelId: null, baseChatOptions: null);
-        Assert.Same(supplied, chatClient.GetService<AIProjectClient>());
-    }
-
-    [Fact]
-    public void Mode3_AgentEndpoint_ThrowsOnNullEndpoint()
-        => Assert.Throws<ArgumentNullException>(() =>
-            new FoundryChatClient(agentEndpoint: null!, credential: new FakeAuthenticationTokenProvider(), clientOptions: null));
-
-    [Fact]
-    public void Mode3_AgentEndpoint_ThrowsOnNullCredential()
-        => Assert.Throws<ArgumentNullException>(() =>
-            new FoundryChatClient(
-                agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-                credential: null!,
-                clientOptions: null));
-
-    #endregion
-
-    #region ParseAgentEndpoint URL parsing
-
-    [Fact]
-    public void ParseAgentEndpoint_HappyPath_ReturnsAgentNameAndProjectRoot()
-    {
-        // Act
-        var (agentName, projectRoot) = FoundryChatClient.ParseAgentEndpoint(
-            new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"));
-
-        // Assert
-        Assert.Equal("myagent", agentName);
-        Assert.Equal("https://example.com/api/projects/myproj", projectRoot.AbsoluteUri.TrimEnd('/'));
-    }
-
-    [Fact]
-    public void ParseAgentEndpoint_TolerantOfTrailingSlash()
-    {
-        // Act
-        var (agentName, _) = FoundryChatClient.ParseAgentEndpoint(
-            new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai/"));
-
-        // Assert
-        Assert.Equal("myagent", agentName);
-    }
-
-    [Fact]
-    public void ParseAgentEndpoint_TolerantOfCaseDifferencesOnAgentsSegment()
-    {
-        // Act
-        var (agentName, _) = FoundryChatClient.ParseAgentEndpoint(
-            new Uri("https://example.com/api/projects/myproj/AGENTS/myagent/endpoint/protocols/openai"));
-
-        // Assert
-        Assert.Equal("myagent", agentName);
-    }
-
-    [Fact]
-    public void ParseAgentEndpoint_StripsQueryAndFragment()
-    {
-        // Act
-        var (_, projectRoot) = FoundryChatClient.ParseAgentEndpoint(
-            new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai?api-version=v1#frag"));
-
-        // Assert
-        Assert.Equal(string.Empty, projectRoot.Query);
-        Assert.Equal(string.Empty, projectRoot.Fragment);
-    }
-
-    [Fact]
-    public void ParseAgentEndpoint_ThrowsOnMissingAgentsSegment()
-        => Assert.Throws<ArgumentException>(() =>
-            FoundryChatClient.ParseAgentEndpoint(new Uri("https://example.com/api/projects/myproj/anyseg/myagent/endpoint/protocols/openai")));
-
-    [Fact]
-    public void ParseAgentEndpoint_ThrowsOnWrongSuffix()
-        => Assert.Throws<ArgumentException>(() =>
-            FoundryChatClient.ParseAgentEndpoint(new Uri("https://example.com/api/projects/myproj/agents/myagent/wrong/suffix")));
-
-    [Fact]
-    public void ParseAgentEndpoint_ThrowsOnNullUri()
-        => Assert.Throws<ArgumentNullException>(() => FoundryChatClient.ParseAgentEndpoint(null!));
-
-    #endregion
-
-    #region AgentFrameworkUserAgentPolicy + ServedModelPolicy registration + dedup
-
-    [Fact]
-    public void Register_AgentFrameworkUserAgentPolicy_OnUnderlyingOpenAIRequestPolicies()
-    {
-        // Arrange + Act: constructing a FoundryChatClient should register the
-        // AgentFrameworkUserAgentPolicy and ServedModelPolicy on the inner chat client's OpenAIRequestPolicies.
-        var chatClient = new FoundryChatClient(CreateProjectClient(), "gpt-4o-mini");
-
-        // Assert: the inner chat client (MEAI's OpenAIResponsesChatClient) exposes
-        // OpenAIRequestPolicies via GetService, and both policies are present in its entries.
-        var policies = chatClient.GetService<OpenAIRequestPolicies>();
-        Assert.NotNull(policies);
-        Assert.Equal(2, EntriesCount(policies!));
-    }
-
-    [Fact]
-    public void Register_AgentFrameworkUserAgentPolicy_IsDedupedAcrossMultipleClients_OnSharedInner()
-    {
-        // Arrange: construct via the ProjectsAgentVersion mode-2 variant, which chains via
-        // :this(...) into the AgentReference ctor. If the policy registration code were
-        // inadvertently called twice along the chain, we would see more than 2 entries.
-        var projectClient = CreateProjectClient();
-        var agentVersion = ModelReaderWriter.Read<ProjectsAgentVersion>(
-            BinaryData.FromString(TestDataUtil.GetAgentVersionResponseJson()))!;
-
-        // Act
-        var chatClient = new FoundryChatClient(projectClient, agentVersion, baseChatOptions: null);
-
-        // Assert: even though the version variant funnels through the AgentReference ctor
-        // via :this(...), each policy is registered exactly once on the inner pipeline.
-        var policies = chatClient.GetService<OpenAIRequestPolicies>();
-        Assert.NotNull(policies);
-        Assert.Equal(2, EntriesCount(policies!));
-        Assert.Same(agentVersion, chatClient.GetService<ProjectsAgentVersion>());
-        Assert.NotNull(chatClient.GetService<AgentReference>());
-    }
-
-    #endregion
-
-    #region Helpers
-
-    private static AIProjectClient CreateProjectClient()
-        => new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(new HttpClient()) });
-
-    private static int EntriesCount(OpenAIRequestPolicies policies)
-    {
-        var field = typeof(OpenAIRequestPolicies).GetField("_entries", BindingFlags.Instance | BindingFlags.NonPublic);
-        Assert.NotNull(field);
-        var arr = (Array)field!.GetValue(policies)!;
-        return arr.Length;
-    }
-
-    #endregion
-}
-#pragma warning restore CS0618
@@ -1,660 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.ClientModel.Primitives;
-using System.Collections.Generic;
-using System.IO;
-using System.Net;
-using System.Net.Http;
-using System.Text;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects;
-using OpenAI.Files;
-
-#pragma warning disable OPENAI001, CS0618
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for the file and vector-store helper methods on <see cref="FoundryChatClient"/>.
-/// Covers all four methods across the three FoundryChatClient construction modes plus argument
-/// validation, cancellation, and request-body shape on the wire.
-/// </summary>
-public sealed class FoundryChatClientVectorStoreTests
-{
-    // ----- Construction helpers shared by every test in this file -----
-
-    private static (FoundryChatClient ChatClient, RequestRecorder Recorder) CreateMode1(string modelId = "gpt-4o-mini", string? responseBody = null)
-    {
-        var recorder = new RequestRecorder(responseBody);
-#pragma warning disable CA5399
-        var httpClient = new HttpClient(recorder);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        return (new FoundryChatClient(projectClient, modelId), recorder);
-    }
-
-    private static (FoundryChatClient ChatClient, RequestRecorder Recorder) CreateMode2(string? responseBody = null)
-    {
-        var recorder = new RequestRecorder(responseBody);
-#pragma warning disable CA5399
-        var httpClient = new HttpClient(recorder);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var agentRef = new AgentReference("agent-name", "1");
-        return (new FoundryChatClient(projectClient, agentRef, defaultModelId: "gpt-4o", baseChatOptions: null), recorder);
-    }
-
-    private static string MakeTempFile(string contents = "hello world")
-    {
-        var path = Path.Combine(Path.GetTempPath(), $"fcc-test-{Guid.NewGuid():N}.txt");
-        File.WriteAllText(path, contents);
-        return path;
-    }
-
-    // ----- UploadFileAsync -----
-
-    [Fact]
-    public async Task UploadFileAsync_Mode1_UploadsViaProjectOpenAIClientAsync()
-    {
-        var (chatClient, recorder) = CreateMode1(responseBody: FakeFileJson("file_abc"));
-        var path = MakeTempFile();
-        try
-        {
-            var result = await chatClient.UploadFileAsync(path, FileUploadPurpose.Assistants);
-
-            Assert.Equal("file_abc", result.Id);
-            Assert.NotEmpty(recorder.Requests);
-            Assert.EndsWith("/files", recorder.Requests[0].PathAndQuery.TrimEnd('/').Split('?')[0]);
-        }
-        finally { File.Delete(path); }
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_Mode2_UploadsViaProjectOpenAIClientAsync()
-    {
-        var (chatClient, recorder) = CreateMode2(responseBody: FakeFileJson("file_xyz"));
-        var path = MakeTempFile();
-        try
-        {
-            var result = await chatClient.UploadFileAsync(path, FileUploadPurpose.Assistants);
-            Assert.Equal("file_xyz", result.Id);
-            Assert.Contains(recorder.Requests, r => r.PathAndQuery.Contains("/files"));
-        }
-        finally { File.Delete(path); }
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_Mode3_UploadsViaMaterializedProjectClientAsync()
-    {
-        // Q-E: Mode 3 (Agent Endpoint) now honors caller-supplied transports via
-        // ProjectOpenAIClientOptions.Transport, so we can use a fake transport here instead of
-        // depending on DNS/network availability against example.com.
-        var sawUpload = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Post && req.RequestUri!.AbsolutePath.Contains("/files", StringComparison.Ordinal))
-            {
-                sawUpload = true;
-                return MakeJsonResponse(FakeFileJson("file_mode3"));
-            }
-            return MakeJsonResponse("{}");
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var chatClient = new FoundryChatClient(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider(),
-            clientOptions: new ProjectOpenAIClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-
-        var path = MakeTempFile();
-        try
-        {
-            var result = await chatClient.UploadFileAsync(path, FileUploadPurpose.Assistants, CancellationToken.None);
-            Assert.True(sawUpload);
-            Assert.Equal("file_mode3", result.Id);
-        }
-        finally { File.Delete(path); }
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_NullFilePath_ThrowsArgumentNullExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            chatClient.UploadFileAsync(null!, FileUploadPurpose.Assistants));
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_FileNotFound_ThrowsFileNotFoundExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        var missing = Path.Combine(Path.GetTempPath(), $"does-not-exist-{Guid.NewGuid():N}.txt");
-        await Assert.ThrowsAsync<FileNotFoundException>(() =>
-            chatClient.UploadFileAsync(missing, FileUploadPurpose.Assistants));
-    }
-
-    [Fact]
-    public async Task UploadFileAsync_HonorsCancellationAsync()
-    {
-        // Cancellation propagation through the OpenAI SDK pipeline surfaces different exception
-        // types depending on the framework target (OperationCanceledException on net10.0,
-        // ObjectDisposedException at the transport layer on net472). Asserting on the exact
-        // exception class is brittle; assert only that the call throws when the token is
-        // pre-cancelled.
-        var (chatClient, _) = CreateMode1(responseBody: FakeFileJson("file_abc"));
-        var path = MakeTempFile();
-        try
-        {
-            using var cts = new CancellationTokenSource();
-            cts.Cancel();
-            await Assert.ThrowsAnyAsync<Exception>(() =>
-                chatClient.UploadFileAsync(path, FileUploadPurpose.Assistants, cts.Token));
-        }
-        finally { File.Delete(path); }
-    }
-
-    // ----- DeleteFileAsync -----
-
-    [Fact]
-    public async Task DeleteFileAsync_Mode1_CallsDeleteOnFileClientAsync()
-    {
-        var (chatClient, recorder) = CreateMode1(responseBody: FakeFileDeletedJson("file_abc"));
-        await chatClient.DeleteFileAsync("file_abc");
-        Assert.Contains(recorder.Requests, r => r.Method == "DELETE" && r.PathAndQuery.Contains("/files/file_abc"));
-    }
-
-    [Fact]
-    public async Task DeleteFileAsync_Mode2_CallsDeleteOnFileClientAsync()
-    {
-        var (chatClient, recorder) = CreateMode2(responseBody: FakeFileDeletedJson("file_xyz"));
-        await chatClient.DeleteFileAsync("file_xyz");
-        Assert.Contains(recorder.Requests, r => r.Method == "DELETE" && r.PathAndQuery.Contains("/files/file_xyz"));
-    }
-
-    [Fact]
-    public async Task DeleteFileAsync_NullId_ThrowsArgumentExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAnyAsync<ArgumentException>(() => chatClient.DeleteFileAsync(null!));
-    }
-
-    [Fact]
-    public async Task DeleteFileAsync_EmptyId_ThrowsArgumentExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAnyAsync<ArgumentException>(() => chatClient.DeleteFileAsync(""));
-    }
-
-    [Fact]
-    public async Task DeleteFileAsync_HonorsCancellationAsync()
-    {
-        // Verify the cancellation token reaches the HTTP pipeline by having the handler
-        // throw OperationCanceledException when the token is cancelled before the request.
-        // This is more robust than asserting on the exact exception the SDK surfaces, which
-        // depends on internal pipeline plumbing.
-        var observedToken = CancellationToken.None;
-        using var handler = new HttpHandlerAssert(async req =>
-        {
-            // We don't have direct access to the SDK's CancellationToken here; instead, sleep
-            // briefly to give the caller's pre-cancellation a chance to be picked up by the
-            // transport. If cancellation reached the pipeline, the await on this handler call
-            // would surface OperationCanceledException; if not, the response is returned.
-            await Task.Delay(50).ConfigureAwait(false);
-            return new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent(FakeFileDeletedJson("file_abc"), Encoding.UTF8, "application/json"),
-            };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        using var cts = new CancellationTokenSource();
-        cts.Cancel();
-        // Any throw is acceptable evidence that cancellation was honored. The SDK's exact
-        // exception surface for pre-cancelled tokens is an implementation detail of
-        // System.ClientModel's pipeline and may differ between versions.
-        await Assert.ThrowsAnyAsync<Exception>(() => chatClient.DeleteFileAsync("file_abc", cts.Token));
-    }
-
-    // ----- CreateVectorStoreAsync -----
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_UploadsThenCreates_WithFileIds_ReturnsVectorStoreAsync()
-    {
-        // Each file POST returns a distinct file id; the recorder dispatches on URL to differentiate.
-        var fileCount = 0;
-        using var handler = new HttpHandlerAssert(async req =>
-        {
-            var body = req.Content is null ? "" : await req.Content.ReadAsStringAsync().ConfigureAwait(false);
-            if (req.RequestUri!.AbsolutePath.Contains("/files") && req.Method == HttpMethod.Post)
-            {
-                fileCount++;
-                return MakeJsonResponse(FakeFileJson($"file_{fileCount}"));
-            }
-            if (req.RequestUri.AbsolutePath.Contains("/vector_stores") && req.Method == HttpMethod.Post)
-            {
-                Assert.Contains("file_1", body);
-                Assert.Contains("file_2", body);
-                Assert.Contains("knowledge-base", body);
-                return MakeJsonResponse(FakeVectorStoreJson("vs_abc", name: "knowledge-base"));
-            }
-            return MakeJsonResponse("{}");
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        var pathA = MakeTempFile("alpha");
-        var pathB = MakeTempFile("beta");
-        try
-        {
-            var store = await chatClient.CreateVectorStoreAsync("knowledge-base", new[] { pathA, pathB });
-            Assert.Equal("vs_abc", store.Id);
-            Assert.Equal(2, fileCount);
-        }
-        finally { File.Delete(pathA); File.Delete(pathB); }
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_WithExpiresAfter_SerializesLastActiveAtAnchorAsync()
-    {
-        string? vectorStoreBody = null;
-        using var handler = new HttpHandlerAssert(async req =>
-        {
-            if (req.RequestUri!.AbsolutePath.Contains("/vector_stores") && req.Method == HttpMethod.Post)
-            {
-                vectorStoreBody = req.Content is null ? "" : await req.Content.ReadAsStringAsync().ConfigureAwait(false);
-                return MakeJsonResponse(FakeVectorStoreJson("vs_abc", name: "x"));
-            }
-            return MakeJsonResponse("{}");
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        await chatClient.CreateVectorStoreAsync("x", Array.Empty<string>(), expiresAfter: TimeSpan.FromDays(7));
-
-        Assert.NotNull(vectorStoreBody);
-        Assert.Contains("\"expires_after\"", vectorStoreBody);
-        Assert.Contains("\"last_active_at\"", vectorStoreBody);
-        Assert.Contains("\"days\":7", vectorStoreBody);
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_WithNullExpiresAfter_OmitsExpirationPolicyAsync()
-    {
-        string? vectorStoreBody = null;
-        using var handler = new HttpHandlerAssert(async req =>
-        {
-            if (req.RequestUri!.AbsolutePath.Contains("/vector_stores") && req.Method == HttpMethod.Post)
-            {
-                vectorStoreBody = req.Content is null ? "" : await req.Content.ReadAsStringAsync().ConfigureAwait(false);
-                return MakeJsonResponse(FakeVectorStoreJson("vs_abc", name: "x"));
-            }
-            return MakeJsonResponse("{}");
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        await chatClient.CreateVectorStoreAsync("x", Array.Empty<string>(), expiresAfter: null);
-
-        Assert.NotNull(vectorStoreBody);
-        Assert.DoesNotContain("\"expires_after\"", vectorStoreBody);
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_EmptyFilesList_CreatesEmptyStoreAsync()
-    {
-        var (chatClient, _) = CreateMode1(responseBody: FakeVectorStoreJson("vs_empty", name: "x"));
-        var store = await chatClient.CreateVectorStoreAsync("x", Array.Empty<string>());
-        Assert.Equal("vs_empty", store.Id);
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_NullName_ThrowsArgumentExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAnyAsync<ArgumentException>(() =>
-            chatClient.CreateVectorStoreAsync(null!, Array.Empty<string>()));
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_NullFilePaths_ThrowsArgumentNullExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAsync<ArgumentNullException>(() =>
-            chatClient.CreateVectorStoreAsync("x", filePaths: null!));
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_HonorsCancellationAsync()
-    {
-        // Same rationale as UploadFileAsync_HonorsCancellationAsync — assert only that any
-        // exception is thrown on a pre-cancelled token.
-        var (chatClient, _) = CreateMode1(responseBody: FakeVectorStoreJson("vs_x", "x"));
-        using var cts = new CancellationTokenSource();
-        cts.Cancel();
-        await Assert.ThrowsAnyAsync<Exception>(() =>
-            chatClient.CreateVectorStoreAsync("x", Array.Empty<string>(), expiresAfter: null, cancellationToken: cts.Token));
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_PollsUntilStoreLeavesInProgress_Async()
-    {
-        // Q-A regression: when the create response returns status=in_progress, the helper must
-        // poll GET /vector_stores/{id} until status changes before returning. Otherwise the
-        // caller receives a half-built store.
-        var pollCount = 0;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.RequestUri!.AbsolutePath.Contains("/vector_stores") && req.Method == HttpMethod.Post)
-            {
-                // First response: status=in_progress.
-                return Task.FromResult(MakeJsonResponse(FakeVectorStoreJsonWithStatus("vs_abc", name: "x", status: "in_progress")));
-            }
-            if (req.RequestUri.AbsolutePath.Contains("/vector_stores/vs_abc") && req.Method == HttpMethod.Get)
-            {
-                pollCount++;
-                // Stay in_progress for two polls, then complete on the third.
-                var status = pollCount < 3 ? "in_progress" : "completed";
-                return Task.FromResult(MakeJsonResponse(FakeVectorStoreJsonWithStatus("vs_abc", name: "x", status: status)));
-            }
-            return Task.FromResult(MakeJsonResponse("{}"));
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        var store = await chatClient.CreateVectorStoreAsync("x", Array.Empty<string>());
-
-        Assert.NotEqual(OpenAI.VectorStores.VectorStoreStatus.InProgress, store.Status);
-        Assert.True(pollCount >= 3, $"Expected at least 3 GET polls before status leaves in_progress; saw {pollCount}.");
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_PollingTimeout_ThrowsTimeoutExceptionAsync()
-    {
-        // Sergey #2: caller-supplied (or default) polling timeout must surface as TimeoutException
-        // when the vector store never leaves InProgress. Mock keeps the store stuck and we pass
-        // a tiny timeout; cancellation token stays unused so the only path that ends the loop
-        // is the timeout check.
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.RequestUri!.AbsolutePath.Contains("/vector_stores", StringComparison.Ordinal))
-            {
-                return Task.FromResult(MakeJsonResponse(FakeVectorStoreJsonWithStatus("vs_stuck", name: "x", status: "in_progress")));
-            }
-            return Task.FromResult(MakeJsonResponse("{}"));
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        var ex = await Assert.ThrowsAsync<TimeoutException>(() =>
-            chatClient.CreateVectorStoreAsync("x", Array.Empty<string>(), expiresAfter: null, pollingTimeout: TimeSpan.FromMilliseconds(500)));
-        Assert.Contains("vs_stuck", ex.Message, StringComparison.Ordinal);
-        Assert.Contains("in-progress", ex.Message, StringComparison.Ordinal);
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_MidUploadFailure_DeletesAlreadyUploadedFilesAsync()
-    {
-        // Q-B regression: when the upload loop throws partway through (e.g. file 3 of 5 is
-        // missing or the network fails), the helper must DELETE the already-uploaded files so
-        // they do not accumulate as orphaned resources. The exception must still propagate.
-        var uploadCount = 0;
-        var deleted = new List<string>();
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            // DELETE first so we don't match the upload-collection /files path against this.
-            if (req.Method == HttpMethod.Delete)
-            {
-                var segments = req.RequestUri!.AbsolutePath.Split('/');
-                var fileId = segments[segments.Length - 1];
-                deleted.Add(fileId);
-                return MakeJsonResponse(FakeFileDeletedJson(fileId));
-            }
-            if (req.Method == HttpMethod.Post && req.RequestUri!.AbsolutePath.Contains("/files", StringComparison.Ordinal))
-            {
-                uploadCount++;
-                if (uploadCount == 3)
-                {
-                    // 400 is non-retriable; the SDK retry policy ignores it. 5xx would trigger
-                    // retries and confuse the assertion on upload count.
-                    return new HttpResponseMessage(HttpStatusCode.BadRequest)
-                    {
-                        Content = new StringContent("{\"error\":{\"code\":\"BadRequest\",\"message\":\"upload-failed-on-3\"}}", Encoding.UTF8, "application/json"),
-                    };
-                }
-                return MakeJsonResponse(FakeFileJson($"file_{uploadCount}"));
-            }
-            return MakeJsonResponse("{}");
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        var paths = new[] { MakeTempFile("a"), MakeTempFile("b"), MakeTempFile("c"), MakeTempFile("d"), MakeTempFile("e") };
-        try
-        {
-            await Assert.ThrowsAnyAsync<Exception>(() => chatClient.CreateVectorStoreAsync("knowledge-base", paths));
-
-            // Three upload attempts: two succeeded, the third threw.
-            Assert.Equal(3, uploadCount);
-            // The two successful uploads must have been deleted as part of best-effort cleanup.
-            Assert.Equal(2, deleted.Count);
-            Assert.Contains("file_1", deleted);
-            Assert.Contains("file_2", deleted);
-        }
-        finally
-        {
-            foreach (var p in paths)
-            {
-                File.Delete(p);
-            }
-        }
-    }
-
-    [Fact]
-    public async Task CreateVectorStoreAsync_MidUploadFailure_CleanupSwallowsDeleteErrorsAsync()
-    {
-        // Q-B follow-on: if a cleanup DELETE itself fails, the helper must still propagate the
-        // original upload exception — not the cleanup exception. The caller cares about the
-        // upload failure; cleanup is best-effort.
-        var uploadCount = 0;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Delete)
-            {
-                return new HttpResponseMessage(HttpStatusCode.BadRequest)
-                {
-                    Content = new StringContent("{\"error\":{\"code\":\"DeleteFailed\",\"message\":\"cleanup-failed\"}}", Encoding.UTF8, "application/json"),
-                };
-            }
-            if (req.Method == HttpMethod.Post && req.RequestUri!.AbsolutePath.Contains("/files", StringComparison.Ordinal))
-            {
-                uploadCount++;
-                if (uploadCount == 2)
-                {
-                    return new HttpResponseMessage(HttpStatusCode.BadRequest)
-                    {
-                        Content = new StringContent("{\"error\":{\"code\":\"BadRequest\",\"message\":\"upload-failed\"}}", Encoding.UTF8, "application/json"),
-                    };
-                }
-                return MakeJsonResponse(FakeFileJson($"file_{uploadCount}"));
-            }
-            return MakeJsonResponse("{}");
-        });
-
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var chatClient = new FoundryChatClient(projectClient, "gpt-4o-mini");
-
-        var paths = new[] { MakeTempFile("a"), MakeTempFile("b") };
-        try
-        {
-            var ex = await Assert.ThrowsAnyAsync<Exception>(() => chatClient.CreateVectorStoreAsync("kb", paths));
-
-            // The original upload-failure message must surface, not the cleanup-failure message.
-            Assert.DoesNotContain("cleanup-failed", ex.Message ?? "", StringComparison.Ordinal);
-        }
-        finally
-        {
-            foreach (var p in paths)
-            {
-                File.Delete(p);
-            }
-        }
-    }
-
-    // ----- DeleteVectorStoreAsync -----
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_Mode1_CallsDeleteAsync()
-    {
-        var (chatClient, recorder) = CreateMode1(responseBody: FakeVectorStoreDeletedJson("vs_abc"));
-        await chatClient.DeleteVectorStoreAsync("vs_abc");
-        Assert.Contains(recorder.Requests, r => r.Method == "DELETE" && r.PathAndQuery.Contains("/vector_stores/vs_abc"));
-    }
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_Mode2_CallsDeleteAsync()
-    {
-        var (chatClient, recorder) = CreateMode2(responseBody: FakeVectorStoreDeletedJson("vs_xyz"));
-        await chatClient.DeleteVectorStoreAsync("vs_xyz");
-        Assert.Contains(recorder.Requests, r => r.Method == "DELETE" && r.PathAndQuery.Contains("/vector_stores/vs_xyz"));
-    }
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_NullId_ThrowsArgumentExceptionAsync()
-    {
-        var (chatClient, _) = CreateMode1();
-        await Assert.ThrowsAnyAsync<ArgumentException>(() => chatClient.DeleteVectorStoreAsync(null!));
-    }
-
-    [Fact]
-    public async Task DeleteVectorStoreAsync_HonorsCancellationAsync()
-    {
-        // Same approach as DeleteFileAsync_HonorsCancellationAsync — assert that the call
-        // throws when the token is pre-cancelled, without asserting on the exact exception
-        // surfaced by the SDK pipeline.
-        var (chatClient, _) = CreateMode1(responseBody: FakeVectorStoreDeletedJson("vs_abc"));
-        using var cts = new CancellationTokenSource();
-        cts.Cancel();
-        await Assert.ThrowsAnyAsync<Exception>(() => chatClient.DeleteVectorStoreAsync("vs_abc", cts.Token));
-    }
-
-    // ----- Fixtures and helpers -----
-
-    private static HttpResponseMessage MakeJsonResponse(string json)
-        => new(HttpStatusCode.OK)
-        {
-            Content = new StringContent(json, Encoding.UTF8, "application/json"),
-        };
-
-    private static string FakeFileJson(string id)
-        => $"{{\"id\":\"{id}\",\"object\":\"file\",\"bytes\":11,\"created_at\":1700000000,\"filename\":\"x.txt\",\"purpose\":\"assistants\",\"status\":\"processed\"}}";
-
-    private static string FakeFileDeletedJson(string id)
-        => $"{{\"id\":\"{id}\",\"object\":\"file\",\"deleted\":true}}";
-
-    private static string FakeVectorStoreJson(string id, string name)
-        => FakeVectorStoreJsonWithStatus(id, name, status: "completed");
-
-    private static string FakeVectorStoreJsonWithStatus(string id, string name, string status)
-        => $"{{\"id\":\"{id}\",\"object\":\"vector_store\",\"created_at\":1700000000,\"name\":\"{name}\",\"usage_bytes\":0,\"file_counts\":{{\"in_progress\":0,\"completed\":0,\"failed\":0,\"cancelled\":0,\"total\":0}},\"status\":\"{status}\",\"last_active_at\":1700000000}}";
-
-    private static string FakeVectorStoreDeletedJson(string id)
-        => $"{{\"id\":\"{id}\",\"object\":\"vector_store.deleted\",\"deleted\":true}}";
-
-    private sealed class RequestRecorder : HttpClientHandler
-    {
-        private readonly string _responseBody;
-        public List<RecordedRequest> Requests { get; } = [];
-
-        public RequestRecorder(string? responseBody)
-        {
-            this._responseBody = responseBody ?? "{}";
-        }
-
-        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
-        {
-            this.Requests.Add(new RecordedRequest
-            {
-                Method = request.Method.Method,
-                PathAndQuery = request.RequestUri?.PathAndQuery ?? "",
-#if NET
-                Body = request.Content is null ? "" : await request.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false),
-#else
-                Body = request.Content is null ? "" : await request.Content.ReadAsStringAsync().ConfigureAwait(false),
-#endif
-            });
-            return MakeJsonResponse(this._responseBody);
-        }
-    }
-
-    private sealed class RecordedRequest
-    {
-        public string Method { get; set; } = "";
-        public string PathAndQuery { get; set; } = "";
-        public string Body { get; set; } = "";
-    }
-}
-#pragma warning restore CS0618
@@ -1,433 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.ClientModel.Primitives;
-using System.Net;
-using System.Net.Http;
-using System.Text;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Extensions.OpenAI;
-using Azure.AI.Projects;
-using Azure.AI.Projects.Agents;
-using Microsoft.Extensions.AI;
-using OpenAI.Responses;
-
-#pragma warning disable OPENAI001, CS0618
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for the public <c>ToPromptAgentAsync</c> extension methods on
-/// <see cref="ChatClientAgent"/> and <see cref="FoundryAgent"/>. Both entry points dispatch
-/// to the same internal converter, so each behavior is asserted through both surfaces.
-/// </summary>
-public sealed class FoundryPromptAgentConverterTests
-{
-    // ----- Failure modes (assert through ChatClientAgent and FoundryAgent extensions) -----
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_NonFoundryChatClient_ThrowsInvalidOperationExceptionAsync()
-    {
-        var agent = new ChatClientAgent(new NoOpChatClient());
-        var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => agent.ToPromptAgentAsync());
-        Assert.Contains("FoundryChatClient", ex.Message);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_FoundryChatClientInMode3_ThrowsInvalidOperationExceptionAsync()
-    {
-        var foundryAgent = new FoundryAgent(
-            agentEndpoint: new Uri("https://example.com/api/projects/myproj/agents/myagent/endpoint/protocols/openai"),
-            credential: new FakeAuthenticationTokenProvider());
-        var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => foundryAgent.ToPromptAgentAsync());
-        Assert.Contains("Agent Endpoint mode (Mode 3)", ex.Message);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_MissingModelId_ThrowsInvalidOperationExceptionAsync()
-    {
-        var projectClient = CreateProjectClient();
-        // Construct a FoundryChatClient via the Responses Agent mode (Mode 1) then wrap in a ChatClientAgent whose
-        // ChatOptions has no ModelId — synthesis must throw.
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions { ChatOptions = new ChatOptions() });
-        var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => agent.ToPromptAgentAsync());
-        Assert.Contains("model id", ex.Message, StringComparison.OrdinalIgnoreCase);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_UnsupportedAITool_ThrowsInvalidOperationExceptionNamingTypeAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions
-            {
-                ModelId = "gpt-4o-mini",
-                Tools = new System.Collections.Generic.List<AITool> { new UnsupportedTool() },
-            },
-        });
-        var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => agent.ToPromptAgentAsync());
-        Assert.Contains(nameof(UnsupportedTool), ex.Message);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_HonorsCancellationAsync()
-    {
-        // Cancellation should bubble up from the AgentReference fetch path. Construct a
-        // FoundryAgent via AsAIAgent(AgentReference) and pass a pre-cancelled token.
-        var (foundryAgent, _) = CreateMode2_PromptAgentOnly("agent-name");
-        using var cts = new CancellationTokenSource();
-        cts.Cancel();
-        await Assert.ThrowsAnyAsync<Exception>(() => foundryAgent.ToPromptAgentAsync(cts.Token));
-    }
-
-    // ----- the Responses Agent mode (Mode 1) (RAPI) synthesis paths -----
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_RoundTripsModelInstructionsTemperatureTopPAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions
-            {
-                ModelId = "gpt-4o-mini",
-                Instructions = "Be helpful.",
-                Temperature = 0.5f,
-                TopP = 0.9f,
-            },
-        });
-
-        var def = await agent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        Assert.Equal("gpt-4o-mini", declarative.Model);
-        Assert.Equal("Be helpful.", declarative.Instructions);
-        Assert.Equal(0.5f, declarative.Temperature);
-        Assert.Equal(0.9f, declarative.TopP);
-        Assert.Empty(declarative.Tools);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_NoTools_ReturnsDefinitionWithEmptyToolsAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions { ModelId = "gpt-4o-mini" },
-        });
-        var def = await agent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        Assert.Empty(declarative.Tools);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_AIFunctionTool_ConvertsToFunctionToolAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var function = AIFunctionFactory.Create(() => "ok", "my_function", "A documented function.");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions
-            {
-                ModelId = "gpt-4o-mini",
-                Tools = new System.Collections.Generic.List<AITool> { function },
-            },
-        });
-
-        var def = await agent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        var fnTool = Assert.Single(declarative.Tools);
-        var ft = Assert.IsType<FunctionTool>(fnTool);
-        Assert.Equal("my_function", ft.FunctionName);
-        Assert.Equal("A documented function.", ft.FunctionDescription);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_FoundryAITool_UnwrapsUnderlyingResponseToolAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions
-            {
-                ModelId = "gpt-4o-mini",
-                Tools = new System.Collections.Generic.List<AITool> { FoundryAITool.CreateWebSearchTool() },
-            },
-        });
-
-        var def = await agent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        var tool = Assert.Single(declarative.Tools);
-        // The unwrapped instance must be the concrete WebSearchTool from the OpenAI SDK.
-        Assert.IsType<WebSearchTool>(tool);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_ChatClientAgent_Mode1_MultipleToolsMixed_ConvertsAllInOrderAsync()
-    {
-        var projectClient = CreateProjectClient();
-        var fcc = new FoundryChatClient(projectClient, "gpt-4o-mini");
-        var function = AIFunctionFactory.Create(() => "ok", "fn", "");
-        var agent = new ChatClientAgent(fcc, new ChatClientAgentOptions
-        {
-            ChatOptions = new ChatOptions
-            {
-                ModelId = "gpt-4o-mini",
-                Tools = new System.Collections.Generic.List<AITool> { function, FoundryAITool.CreateWebSearchTool() },
-            },
-        });
-
-        var def = await agent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        Assert.Equal(2, declarative.Tools.Count);
-        Assert.IsType<FunctionTool>(declarative.Tools[0]);
-        Assert.IsType<WebSearchTool>(declarative.Tools[1]);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode1_ResultIsDeclarativeAgentDefinitionAsync()
-    {
-        // FoundryAgent constructed via the projectEndpoint+model+instructions ctor (Responses Agent mode, the Responses Agent mode (Mode 1)).
-        var foundryAgent = new FoundryAgent(
-            projectEndpoint: new Uri("https://test.openai.azure.com/"),
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "You are helpful.");
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        Assert.Equal("gpt-4o-mini", declarative.Model);
-        Assert.Equal("You are helpful.", declarative.Instructions);
-    }
-
-    // ----- the Prompt Agent mode (Mode 2) paths -----
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_AgentVersion_ReturnsCachedDefinitionAsync()
-    {
-        // Construct via ProjectsAgentVersion → the Definition reference must come back unchanged.
-        var version = ModelReaderWriter.Read<ProjectsAgentVersion>(BinaryData.FromString(TestDataUtil.GetAgentVersionResponseJson()))!;
-        var projectClient = CreateProjectClient();
-        var foundryAgent = projectClient.AsAIAgent(version);
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-        Assert.Same(version.Definition, def);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_AgentRecord_ReturnsLatestVersionDefinitionAsync()
-    {
-        var record = ModelReaderWriter.Read<ProjectsAgentRecord>(BinaryData.FromString(TestDataUtil.GetAgentResponseJson()))!;
-        var projectClient = CreateProjectClient();
-        var foundryAgent = projectClient.AsAIAgent(record);
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-        Assert.Same(record.GetLatestVersion().Definition, def);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_PromptAgentOnly_FetchesLatestVersionAsync()
-    {
-        // The handler returns a known agent JSON. The converter must hit GET /agents/{name}
-        // and return that record's latest version definition.
-        var fetched = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Get && req.RequestUri!.AbsolutePath.Contains("/agents/agent-name"))
-            {
-                fetched = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(TestDataUtil.GetAgentResponseJson(agentName: "agent-name"), Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var foundryAgent = projectClient.AsAIAgent(new AgentReference("agent-name"));
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-        Assert.True(fetched);
-        Assert.NotNull(def);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_PromptAgentOnly_PinnedVersion_FetchesPinnedVersionAsync()
-    {
-        // Q-C regression: when AgentReference.Version is set, the converter must call
-        // GET /agents/{name}/versions/{version} and return that pinned version's definition,
-        // NOT GET /agents/{name} -> GetLatestVersion() which would silently substitute the
-        // server's latest. We probe both paths from the same handler and assert exactly one was hit.
-        var fetchedLatest = false;
-        var fetchedPinned = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            // Pinned-version path: …/agents/{name}/versions/{version}
-            if (req.Method == HttpMethod.Get && req.RequestUri!.AbsolutePath.Contains("/agents/agent-name/versions/2", StringComparison.Ordinal))
-            {
-                fetchedPinned = true;
-                var pinnedDef = new DeclarativeAgentDefinition("gpt-pinned") { Instructions = "Pinned-version instructions." };
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(TestDataUtil.GetAgentVersionResponseJson(agentName: "agent-name", agentDefinition: pinnedDef), Encoding.UTF8, "application/json"),
-                };
-            }
-            // Latest-version path: …/agents/{name}
-            if (req.Method == HttpMethod.Get && req.RequestUri!.AbsolutePath.EndsWith("/agents/agent-name", StringComparison.Ordinal))
-            {
-                fetchedLatest = true;
-                var latestDef = new DeclarativeAgentDefinition("gpt-latest") { Instructions = "Latest-version instructions." };
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(TestDataUtil.GetAgentResponseJson(agentName: "agent-name", agentDefinition: latestDef), Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var foundryAgent = projectClient.AsAIAgent(new AgentReference("agent-name", "2"));
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-
-        Assert.True(fetchedPinned, "Pinned-version endpoint (.../agents/agent-name/versions/2) must be called when AgentReference.Version is set.");
-        Assert.False(fetchedLatest, "Latest-version endpoint (.../agents/agent-name) must NOT be called when AgentReference.Version is set.");
-        var declarative = Assert.IsType<DeclarativeAgentDefinition>(def);
-        Assert.Equal("gpt-pinned", declarative.Model);
-        Assert.Equal("Pinned-version instructions.", declarative.Instructions);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_PromptAgentOnly_UnpinnedVersionKeyword_FetchesLatestAsync()
-    {
-        // Q-C boundary: AgentReference.Version == "latest" must fall back to the GET /agents/{name}
-        // path (the latest-version path), NOT GET /agents/{name}/versions/latest.
-        var fetchedLatest = false;
-        using var handler = new HttpHandlerAssert(req =>
-        {
-            if (req.Method == HttpMethod.Get && req.RequestUri!.AbsolutePath.EndsWith("/agents/agent-name", StringComparison.Ordinal))
-            {
-                fetchedLatest = true;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent(TestDataUtil.GetAgentResponseJson(agentName: "agent-name"), Encoding.UTF8, "application/json"),
-                };
-            }
-            return new HttpResponseMessage(HttpStatusCode.OK) { Content = new StringContent("{}", Encoding.UTF8, "application/json") };
-        });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var foundryAgent = projectClient.AsAIAgent(new AgentReference("agent-name", "latest"));
-
-        var def = await foundryAgent.ToPromptAgentAsync();
-
-        Assert.True(fetchedLatest);
-        Assert.NotNull(def);
-    }
-
-    [Fact]
-    public async Task ToPromptAgentAsync_FoundryAgent_Mode2_PromptAgentOnly_ServerReturnsError_PropagatesExceptionAsync()
-    {
-        using var handler = new HttpHandlerAssert(req =>
-            new HttpResponseMessage(HttpStatusCode.NotFound) { Content = new StringContent("{\"error\":{\"code\":\"NotFound\"}}", Encoding.UTF8, "application/json") });
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(httpClient) });
-        var foundryAgent = projectClient.AsAIAgent(new AgentReference("missing-agent"));
-
-        await Assert.ThrowsAnyAsync<Exception>(() => foundryAgent.ToPromptAgentAsync());
-    }
-
-    // ----- Python-parity guard: both extensions produce equivalent definitions -----
-
-    [Fact]
-    public async Task BothExtensions_ProduceEquivalentDefinitions_ForEquivalentInputsAsync()
-    {
-        // Build two agents that are semantically equivalent: one as a plain ChatClientAgent
-        // via AsAIAgent(model, instructions), and one as a FoundryAgent via the projectEndpoint
-        // ctor. Both flow through the same converter; assert key fields match.
-        var projectClient = CreateProjectClient();
-        ChatClientAgent ccaAgent = projectClient.AsAIAgent("gpt-4o-mini", "Be helpful.");
-        var foundryAgent = new FoundryAgent(
-            projectEndpoint: new Uri("https://test.openai.azure.com/"),
-            credential: new FakeAuthenticationTokenProvider(),
-            model: "gpt-4o-mini",
-            instructions: "Be helpful.");
-
-        var ccaDef = await ccaAgent.ToPromptAgentAsync();
-        var faDef = await foundryAgent.ToPromptAgentAsync();
-
-        var a = Assert.IsType<DeclarativeAgentDefinition>(ccaDef);
-        var b = Assert.IsType<DeclarativeAgentDefinition>(faDef);
-        Assert.Equal(a.Model, b.Model);
-        Assert.Equal(a.Instructions, b.Instructions);
-        Assert.Equal(a.Tools.Count, b.Tools.Count);
-    }
-
-    // ----- Helpers -----
-
-    private static AIProjectClient CreateProjectClient()
-        => new(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(new HttpClient()) });
-
-    private static (FoundryAgent FoundryAgent, AIProjectClient ProjectClient) CreateMode2_PromptAgentOnly(string agentName)
-    {
-        var projectClient = CreateProjectClient();
-        var foundryAgent = projectClient.AsAIAgent(new AgentReference(agentName));
-        return (foundryAgent, projectClient);
-    }
-
-    private sealed class NoOpChatClient : IChatClient
-    {
-        public Task<ChatResponse> GetResponseAsync(System.Collections.Generic.IEnumerable<ChatMessage> messages, ChatOptions? options = null, CancellationToken cancellationToken = default)
-            => Task.FromResult(new ChatResponse());
-
-        public System.Collections.Generic.IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(System.Collections.Generic.IEnumerable<ChatMessage> messages, ChatOptions? options = null, CancellationToken cancellationToken = default)
-            => EmptyAsyncEnumerableAsync();
-
-        private static async System.Collections.Generic.IAsyncEnumerable<ChatResponseUpdate> EmptyAsyncEnumerableAsync()
-        {
-            await Task.CompletedTask.ConfigureAwait(false);
-            yield break;
-        }
-
-        public object? GetService(Type serviceType, object? serviceKey = null) => null;
-
-        public void Dispose() { }
-    }
-
-    private sealed class UnsupportedTool : AITool
-    {
-        public override string Name => "unsupported";
-    }
-}
-#pragma warning restore CS0618
@@ -1,90 +0,0 @@
-// 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;
-using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
-using OpenAI;
-using OpenAI.Responses;
-
-#pragma warning disable OPENAI001
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// One-shot verification (kept in tree to detect regressions) that MEAI 10.5.1 stamps its own
-/// <c>MEAI/{version}</c> User-Agent segment automatically when an <see cref="ResponsesClient"/>
-/// is wrapped via <c>AsIChatClient()</c>. If this test starts failing, the FoundryChatClient
-/// implementation must re-register the MEAI policy explicitly via OpenAIRequestPolicies because
-/// the local Foundry copy was deleted under the assumption that MEAI provides it built-in.
-/// </summary>
-public sealed class MeaiAutoUserAgentVerificationTests
-{
-    [Fact]
-    public async Task MeaiOpenAIResponsesClient_StampsMeaiSegmentAutomatically_WithoutLocalPolicyAsync()
-    {
-        // Arrange: bare OpenAI ResponseClient over a fake HTTP transport, wrapped via MEAI's
-        // AsIChatClient() with no custom OpenAIRequestPolicies registration. If MEAI auto-stamps
-        // its own MEAI/{version} segment, it will appear here.
-        using var handler = new RecordingHandler();
-#pragma warning disable CA5399
-        using var httpClient = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var options = new OpenAIClientOptions
-        {
-            Transport = new HttpClientPipelineTransport(httpClient),
-            Endpoint = new Uri("https://example.test/v1"),
-        };
-
-        var responseClient = new ResponsesClient(new ApiKeyCredential("test-key"), options);
-        var chatClient = responseClient.AsIChatClient("gpt-4o-mini");
-
-        // Act: send a request through MEAI's chat client. The fake transport will throw on
-        // response parsing, but we only care about the outbound headers, which are captured
-        // before the response is parsed.
-        try
-        {
-            await chatClient.GetResponseAsync("hi", cancellationToken: CancellationToken.None);
-        }
-        catch
-        {
-            // Expected: the fake response body is not parseable as a Responses API payload.
-        }
-
-        // Assert: at least one outbound request reached the transport, and its User-Agent
-        // contains either "MEAI/" (auto-stamped by MEAI) or no MEAI segment (verification
-        // signal — see test summary).
-        Assert.True(handler.Count > 0, "Expected at least one outbound request from MEAI wrapper.");
-        Assert.NotNull(handler.LastUserAgent);
-        // INTENT: assert that MEAI auto-stamps. If the assertion fails, see the FoundryChatClient
-        // implementation note about needing to register the MEAI policy explicitly.
-        Assert.Contains("MEAI/", handler.LastUserAgent);
-    }
-
-    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);
-        }
-    }
-}
@@ -14,14 +14,11 @@
    <ProjectReference Include="..\..\src\Microsoft.Agents.AI.Foundry\Microsoft.Agents.AI.Foundry.csproj" />
  </ItemGroup>

-  <!-- Tests requiring net8.0+ (MEAI.Evaluation and some SCM pipeline APIs do 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" />
    <Compile Remove="ClientHeadersExtensionsTests.cs" />
-    <Compile Remove="ServedModelTestHelpers.cs" />
-    <Compile Remove="ServedModelScopeTests.cs" />
-    <Compile Remove="ServedModelPolicyTests.cs" />
  </ItemGroup>

  <ItemGroup>
@@ -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 UserAgentResponsesClient → 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);
+        }
+    }
+}
@@ -1,84 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Threading.Tasks;
-using Microsoft.Extensions.AI;
-
-#pragma warning disable OPENAI001, MEAI001, MAAI001, SCME0001
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for <see cref="ServedModelPolicy"/>: the SCM pipeline policy that reads the
-/// <c>x-ms-served-model</c> response header and writes it into the active
-/// <see cref="ServedModelScope"/> box.
-/// </summary>
-/// <remarks>
-/// Tests drive the policy through a real OpenAI ResponsesClient SCM pipeline against a mock
-/// HTTP handler so the policy executes in its production configuration.
-/// </remarks>
-public sealed class ServedModelPolicyTests
-{
-    [Fact]
-    public void Instance_IsSingleton()
-    {
-        Assert.Same(ServedModelPolicy.Instance, ServedModelPolicy.Instance);
-    }
-
-    [Fact]
-    public async Task ProcessAsync_HeaderPresent_SetsModelIdOnResponseAsync()
-    {
-        // Arrange
-        using var handler = new ServedModelTestHelpers.ServedModelHandler(ServedModelTestHelpers.MinimalResponseJson(), servedModel: "gpt-5-nano-2025-08-07");
-        IChatClient chatClient = ServedModelTestHelpers.CreateChatClientWithPolicy(handler);
-
-        // Act
-        var response = await chatClient.GetResponseAsync("hi");
-
-        // Assert
-        Assert.Equal("gpt-5-nano-2025-08-07", response.ModelId);
-    }
-
-    [Fact]
-    public async Task ProcessAsync_HeaderAbsent_PreservesModelIdFromBodyAsync()
-    {
-        // Arrange
-        using var handler = new ServedModelTestHelpers.ServedModelHandler(ServedModelTestHelpers.MinimalResponseJson(), servedModel: null);
-        IChatClient chatClient = ServedModelTestHelpers.CreateChatClientWithPolicy(handler);
-
-        // Act
-        var response = await chatClient.GetResponseAsync("hi");
-
-        // Assert: ModelId is the deployment alias from the JSON body ("fake").
-        Assert.Equal("fake", response.ModelId);
-    }
-
-    [Theory]
-    [InlineData("")]
-    [InlineData("   ")]
-    public async Task ProcessAsync_EmptyOrWhitespaceHeader_PreservesModelIdFromBodyAsync(string headerValue)
-    {
-        // Arrange
-        using var handler = new ServedModelTestHelpers.ServedModelHandler(ServedModelTestHelpers.MinimalResponseJson(), servedModel: headerValue);
-        IChatClient chatClient = ServedModelTestHelpers.CreateChatClientWithPolicy(handler);
-
-        // Act
-        var response = await chatClient.GetResponseAsync("hi");
-
-        // Assert: empty/whitespace header is rejected by the policy, ModelId stays as "fake".
-        Assert.Equal("fake", response.ModelId);
-    }
-
-    [Fact]
-    public async Task ProcessAsync_HeaderWithSurroundingWhitespace_TrimsValueAsync()
-    {
-        // Arrange
-        using var handler = new ServedModelTestHelpers.ServedModelHandler(ServedModelTestHelpers.MinimalResponseJson(), servedModel: "  gpt-5-nano-2025-08-07  ");
-        IChatClient chatClient = ServedModelTestHelpers.CreateChatClientWithPolicy(handler);
-
-        // Act
-        var response = await chatClient.GetResponseAsync("hi");
-
-        // Assert
-        Assert.Equal("gpt-5-nano-2025-08-07", response.ModelId);
-    }
-}
@@ -1,40 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Runtime.CompilerServices;
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Unit tests for <see cref="ServedModelScope"/>: the AsyncLocal carrier that bridges the
-/// served-model value from the SCM pipeline policy up to the delegating chat client.
-/// </summary>
-public sealed class ServedModelScopeTests
-{
-    [Fact]
-    public void Current_DefaultIsNull()
-    {
-        Assert.Null(ServedModelScope.Current);
-    }
-
-    [Fact]
-    public void Current_SetAndGet_ReturnsBox()
-    {
-        // Arrange
-        var previous = ServedModelScope.Current;
-
-        try
-        {
-            // Act
-            var box = new StrongBox<string?>("gpt-5-nano-2025-08-07");
-            ServedModelScope.Current = box;
-
-            // Assert
-            Assert.Same(box, ServedModelScope.Current);
-            Assert.Equal("gpt-5-nano-2025-08-07", ServedModelScope.Current!.Value);
-        }
-        finally
-        {
-            ServedModelScope.Current = previous;
-        }
-    }
-}
@@ -1,80 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.ClientModel.Primitives;
-using System.Net;
-using System.Net.Http;
-using System.Text;
-using System.Threading;
-using System.Threading.Tasks;
-using Azure.AI.Projects;
-using Microsoft.Extensions.AI;
-
-#pragma warning disable OPENAI001, MEAI001, MAAI001, SCME0001
-
-namespace Microsoft.Agents.AI.Foundry.UnitTests;
-
-/// <summary>
-/// Shared helpers and fake clients used by the served-model test suite
-/// (<see cref="ServedModelScopeTests"/>, <see cref="ServedModelPolicyTests"/>).
-/// </summary>
-internal static class ServedModelTestHelpers
-{
-    public 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}
-        }
-        """;
-
-    /// <summary>
-    /// Creates a <see cref="FoundryChatClient"/> backed by a real OpenAI Responses pipeline
-    /// routed through the supplied <paramref name="handler"/>. The <see cref="ServedModelPolicy"/>
-    /// is registered automatically by the <see cref="FoundryChatClient"/> constructor.
-    /// </summary>
-    public static IChatClient CreateChatClientWithPolicy(HttpMessageHandler handler)
-    {
-#pragma warning disable CA5399
-        var http = new HttpClient(handler);
-#pragma warning restore CA5399
-
-        var projectClient = new AIProjectClient(
-            new Uri("https://test.openai.azure.com/"),
-            new FakeAuthenticationTokenProvider(),
-            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(http) });
-
-        return new FoundryChatClient(projectClient, "fake");
-    }
-
-    /// <summary>
-    /// An <see cref="HttpClientHandler"/> that returns a fixed response body and optionally
-    /// includes the <c>x-ms-served-model</c> response header.
-    /// </summary>
-    public sealed class ServedModelHandler : HttpClientHandler
-    {
-        private readonly string _body;
-        private readonly string? _servedModel;
-
-        public ServedModelHandler(string body, string? servedModel)
-        {
-            this._body = body;
-            this._servedModel = servedModel;
-        }
-
-        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
-        {
-            var resp = new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent(this._body, Encoding.UTF8, "application/json"),
-                RequestMessage = request,
-            };
-
-            if (this._servedModel is not null)
-            {
-                resp.Headers.Add("x-ms-served-model", this._servedModel);
-            }
-
-            return Task.FromResult(resp);
-        }
-    }
-}
@@ -1,9 +1,6 @@
 // Copyright (c) Microsoft. All rights reserved.

 using Moq;
-#if NET
-using Microsoft.Agents.AI.Tools.Shell;
-#endif

 namespace Microsoft.Agents.AI.UnitTests;

@@ -40,12 +37,6 @@ public class HarnessAgentOptionsTests
        Assert.Null(options.FileAccessStore);
        Assert.Null(options.AgentModeProviderOptions);
        Assert.Null(options.AgentSkillsSource);
-        Assert.Null(options.BackgroundAgents);
-        Assert.Null(options.BackgroundAgentsProviderOptions);
-#if NET
-        Assert.Null(options.ShellExecutor);
-        Assert.Null(options.ShellEnvironmentProviderOptions);
-#endif
    }

    /// <summary>
@@ -61,12 +52,6 @@ public class HarnessAgentOptionsTests
        var fileAccessStore = new Mock<AgentFileStore>().Object;
        var agentModeOptions = new AgentModeProviderOptions();
        var skillsSource = new Mock<AgentSkillsSource>().Object;
-        var backgroundAgents = new AIAgent[] { new Mock<AIAgent>().Object };
-        var backgroundAgentsOptions = new BackgroundAgentsProviderOptions();
-#if NET
-        var shellExecutor = new Mock<ShellExecutor>().Object;
-        var shellEnvOptions = new ShellEnvironmentProviderOptions();
-#endif

        // Act
        var options = new HarnessAgentOptions
@@ -92,12 +77,6 @@ public class HarnessAgentOptionsTests
            AgentSkillsSource = skillsSource,
            DisableOpenTelemetry = true,
            OpenTelemetrySourceName = "custom-source",
-            BackgroundAgents = backgroundAgents,
-            BackgroundAgentsProviderOptions = backgroundAgentsOptions,
-#if NET
-            ShellExecutor = shellExecutor,
-            ShellEnvironmentProviderOptions = shellEnvOptions,
-#endif
        };

        // Assert
@@ -124,11 +103,5 @@ public class HarnessAgentOptionsTests
        Assert.Same(skillsSource, options.AgentSkillsSource);
        Assert.True(options.DisableOpenTelemetry);
        Assert.Equal("custom-source", options.OpenTelemetrySourceName);
-        Assert.Same(backgroundAgents, options.BackgroundAgents);
-        Assert.Same(backgroundAgentsOptions, options.BackgroundAgentsProviderOptions);
-#if NET
-        Assert.Same(shellExecutor, options.ShellExecutor);
-        Assert.Same(shellEnvOptions, options.ShellEnvironmentProviderOptions);
-#endif
    }
 }
@@ -5,9 +5,6 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
-#if NET
-using Microsoft.Agents.AI.Tools.Shell;
-#endif
 using Microsoft.Extensions.AI;
 using Moq;

@@ -1200,264 +1197,4 @@ public class HarnessAgentTests
    }

    #endregion
-
-    #region Feature: BackgroundAgentsProvider
-
-    /// <summary>
-    /// Verify that BackgroundAgentsProvider is included when BackgroundAgents are specified.
-    /// </summary>
-    [Fact]
-    public void BackgroundAgentsProvider_IncludedWhenAgentsSpecified()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var bgAgentMock = new Mock<AIAgent>();
-        bgAgentMock.Setup(a => a.Name).Returns("TestBackgroundAgent");
-        var options = CreateAllDisabledOptions();
-        options.BackgroundAgents = [bgAgentMock.Object];
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert
-        Assert.NotNull(innerAgent?.AIContextProviders);
-        Assert.Contains(innerAgent!.AIContextProviders!, p => p is BackgroundAgentsProvider);
-    }
-
-    /// <summary>
-    /// Verify that BackgroundAgentsProvider is not included when BackgroundAgents is null.
-    /// </summary>
-    [Fact]
-    public void BackgroundAgentsProvider_ExcludedWhenAgentsNull()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var options = CreateAllDisabledOptions();
-        options.BackgroundAgents = null;
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert
-        Assert.NotNull(innerAgent);
-        if (innerAgent!.AIContextProviders != null)
-        {
-            Assert.DoesNotContain(innerAgent.AIContextProviders, p => p is BackgroundAgentsProvider);
-        }
-    }
-
-    /// <summary>
-    /// Verify that BackgroundAgentsProvider is not included when BackgroundAgents is an empty collection.
-    /// </summary>
-    [Fact]
-    public void BackgroundAgentsProvider_ExcludedWhenAgentsEmpty()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var options = CreateAllDisabledOptions();
-        options.BackgroundAgents = Array.Empty<AIAgent>();
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert
-        Assert.NotNull(innerAgent);
-        if (innerAgent!.AIContextProviders != null)
-        {
-            Assert.DoesNotContain(innerAgent.AIContextProviders, p => p is BackgroundAgentsProvider);
-        }
-    }
-
-    /// <summary>
-    /// Verify that BackgroundAgentsProviderOptions is passed through when specified.
-    /// </summary>
-    [Fact]
-    public async Task BackgroundAgentsProvider_UsesProvidedOptionsAsync()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var bgAgentMock = new Mock<AIAgent>();
-        bgAgentMock.Setup(a => a.Name).Returns("TestBackgroundAgent");
-        bgAgentMock.Setup(a => a.Description).Returns("A test background agent");
-        var providerOptions = new BackgroundAgentsProviderOptions
-        {
-            Instructions = "Custom instructions with {background_agents} list.",
-        };
-        var options = CreateAllDisabledOptions();
-        options.BackgroundAgents = [bgAgentMock.Object];
-        options.BackgroundAgentsProviderOptions = providerOptions;
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-        var bgProvider = innerAgent!.AIContextProviders!.OfType<BackgroundAgentsProvider>().Single();
-
-#pragma warning disable MAAI001
-        var invokingContext = new AIContextProvider.InvokingContext(
-            new Mock<AIAgent>().Object,
-            new Mock<AgentSession>().Object,
-            new AIContext());
-#pragma warning restore MAAI001
-
-        AIContext result = await bgProvider.InvokingAsync(invokingContext);
-
-        // Assert — custom instructions template is used and agent info is included
-        Assert.NotNull(result.Instructions);
-        Assert.Contains("Custom instructions with", result.Instructions);
-        Assert.Contains("TestBackgroundAgent", result.Instructions);
-    }
-
-    /// <summary>
-    /// Verify that multiple background agents are all passed to the provider.
-    /// </summary>
-    [Fact]
-    public async Task BackgroundAgentsProvider_IncludesMultipleAgentsAsync()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var agent1Mock = new Mock<AIAgent>();
-        agent1Mock.Setup(a => a.Name).Returns("Agent1");
-        agent1Mock.Setup(a => a.Description).Returns("First agent");
-        var agent2Mock = new Mock<AIAgent>();
-        agent2Mock.Setup(a => a.Name).Returns("Agent2");
-        agent2Mock.Setup(a => a.Description).Returns("Second agent");
-        var options = CreateAllDisabledOptions();
-        options.BackgroundAgents = [agent1Mock.Object, agent2Mock.Object];
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-        var bgProvider = innerAgent!.AIContextProviders!.OfType<BackgroundAgentsProvider>().Single();
-
-#pragma warning disable MAAI001
-        var invokingContext = new AIContextProvider.InvokingContext(
-            new Mock<AIAgent>().Object,
-            new Mock<AgentSession>().Object,
-            new AIContext());
-#pragma warning restore MAAI001
-
-        AIContext result = await bgProvider.InvokingAsync(invokingContext);
-
-        // Assert — both agents appear in the provider's instructions
-        Assert.NotNull(result.Instructions);
-        Assert.Contains("Agent1", result.Instructions);
-        Assert.Contains("First agent", result.Instructions);
-        Assert.Contains("Agent2", result.Instructions);
-        Assert.Contains("Second agent", result.Instructions);
-    }
-
-    #endregion
-
-#if NET
-    #region Feature: ShellEnvironmentProvider
-
-    /// <summary>
-    /// Verify that ShellEnvironmentProvider is included when ShellExecutor is provided.
-    /// </summary>
-    [Fact]
-    public void ShellEnvironmentProvider_IncludedWhenExecutorProvided()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var executorMock = new Mock<ShellExecutor>();
-        executorMock.Setup(e => e.AsAIFunction(It.IsAny<string>(), It.IsAny<string?>(), It.IsAny<bool>()))
-            .Returns(AIFunctionFactory.Create(() => "test", "run_shell"));
-        var options = CreateAllDisabledOptions();
-        options.ShellExecutor = executorMock.Object;
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert
-        Assert.NotNull(innerAgent?.AIContextProviders);
-        Assert.Contains(innerAgent!.AIContextProviders!, p => p is ShellEnvironmentProvider);
-    }
-
-    /// <summary>
-    /// Verify that ShellEnvironmentProvider is not included when ShellExecutor is null.
-    /// </summary>
-    [Fact]
-    public void ShellEnvironmentProvider_ExcludedWhenExecutorNull()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var options = CreateAllDisabledOptions();
-        options.ShellExecutor = null;
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert
-        Assert.NotNull(innerAgent);
-        Assert.NotNull(innerAgent!.AIContextProviders);
-        Assert.DoesNotContain(innerAgent.AIContextProviders!, p => p is ShellEnvironmentProvider);
-    }
-
-    /// <summary>
-    /// Verify that the shell tool AIFunction is added to ChatOptions.Tools when ShellExecutor is provided.
-    /// </summary>
-    [Fact]
-    public async Task ShellExecutor_ToolAddedToChatOptionsAsync()
-    {
-        // Arrange
-        ChatOptions? capturedOptions = null;
-        var chatClientMock = new Mock<IChatClient>();
-        chatClientMock
-            .Setup(c => c.GetResponseAsync(It.IsAny<IEnumerable<ChatMessage>>(), It.IsAny<ChatOptions>(), It.IsAny<CancellationToken>()))
-            .Callback<IEnumerable<ChatMessage>, ChatOptions?, CancellationToken>((_, opts, _) => capturedOptions = opts)
-            .ReturnsAsync(new ChatResponse(new ChatMessage(ChatRole.Assistant, "done")));
-
-        var executorMock = new Mock<ShellExecutor>();
-        executorMock.Setup(e => e.AsAIFunction(It.IsAny<string>(), It.IsAny<string?>(), It.IsAny<bool>()))
-            .Returns(AIFunctionFactory.Create(() => "shell output", "run_shell"));
-
-        var options = CreateAllDisabledOptions();
-        options.DisableWebSearch = true;
-        options.ShellExecutor = executorMock.Object;
-
-        // Act
-        var agent = new HarnessAgent(chatClientMock.Object, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var session = await agent.CreateSessionAsync();
-        await agent.RunAsync([new ChatMessage(ChatRole.User, "Hi")], session);
-
-        // Assert — the shell tool should be present
-        Assert.NotNull(capturedOptions?.Tools);
-        Assert.Contains(capturedOptions!.Tools!, t => t is AIFunction f && f.Name == "run_shell");
-    }
-
-    /// <summary>
-    /// Verify that ShellEnvironmentProvider is present when ShellEnvironmentProviderOptions is also specified.
-    /// </summary>
-    [Fact]
-    public void ShellEnvironmentProvider_PresentWhenOptionsProvided()
-    {
-        // Arrange
-        var chatClient = new Mock<IChatClient>().Object;
-        var executorMock = new Mock<ShellExecutor>();
-        executorMock.Setup(e => e.AsAIFunction(It.IsAny<string>(), It.IsAny<string?>(), It.IsAny<bool>()))
-            .Returns(AIFunctionFactory.Create(() => "test", "run_shell"));
-        var envOptions = new ShellEnvironmentProviderOptions
-        {
-            ProbeTools = ["git", "python"],
-        };
-        var options = CreateAllDisabledOptions();
-        options.ShellExecutor = executorMock.Object;
-        options.ShellEnvironmentProviderOptions = envOptions;
-
-        // Act
-        var agent = new HarnessAgent(chatClient, TestMaxContextWindowTokens, TestMaxOutputTokens, options);
-        var innerAgent = agent.GetService<ChatClientAgent>();
-
-        // Assert — provider should exist (options wiring is validated by the provider's behavior)
-        Assert.NotNull(innerAgent?.AIContextProviders);
-        Assert.Contains(innerAgent!.AIContextProviders!, p => p is ShellEnvironmentProvider);
-    }
-
-    #endregion
-#endif
 }
@@ -1,15 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-/// <summary>
-/// Minimal empty <see cref="IServiceProvider"/> for in-memory fixtures that don't use DI.
-/// </summary>
-internal sealed class EmptyServiceProvider : IServiceProvider
-{
-    public static EmptyServiceProvider Instance { get; } = new();
-
-    public object? GetService(Type serviceType) => null;
-}
@@ -1,127 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.IO;
-using System.IO.Pipelines;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.Extensions.Logging.Abstractions;
-using ModelContextProtocol;
-using ModelContextProtocol.Client;
-using ModelContextProtocol.Protocol;
-using ModelContextProtocol.Server;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-/// <summary>
-/// In-process MCP server fixture that pairs a <see cref="McpServer"/> and a <see cref="McpClient"/>
-/// over duplex <see cref="Pipe"/>-backed streams so unit tests can exercise the
-/// real task-augmentation protocol without spawning a child process or opening a socket.
-/// </summary>
-internal sealed class InMemoryMcpServerFixture : IAsyncDisposable
-{
-    private readonly McpServer _server;
-    private readonly Task _serverLoop;
-    private readonly CancellationTokenSource _cts;
-
-    public McpClient Client { get; }
-
-    private InMemoryMcpServerFixture(McpServer server, McpClient client, Task serverLoop, CancellationTokenSource cts)
-    {
-        this._server = server;
-        this.Client = client;
-        this._serverLoop = serverLoop;
-        this._cts = cts;
-    }
-
-    public static async Task<InMemoryMcpServerFixture> CreateAsync(
-        McpServerPrimitiveCollection<McpServerTool> tools,
-        CancellationToken cancellationToken = default)
-    {
-        Pipe clientToServer = new();
-        Pipe serverToClient = new();
-
-        // Stream conventions:
-        //   StreamClientTransport(serverInput, serverOutput, ...): serverInput is what the client
-        //   WRITES to (server reads it); serverOutput is what the client READS from (server writes it).
-        //   StreamServerTransport(input, output, ...): input is what the server READS from; output
-        //   is what the server WRITES to.
-        Stream clientWriteStream = clientToServer.Writer.AsStream();
-        Stream clientReadStream = serverToClient.Reader.AsStream();
-        Stream serverReadStream = clientToServer.Reader.AsStream();
-        Stream serverWriteStream = serverToClient.Writer.AsStream();
-
-        StreamServerTransport serverTransport = new(
-            serverReadStream,
-            serverWriteStream,
-            "test-server",
-            NullLoggerFactory.Instance);
-
-        McpServerOptions serverOptions = new()
-        {
-            ServerInfo = new Implementation { Name = "test-server", Version = "1.0.0" },
-            TaskStore = new InMemoryMcpTaskStore(),
-            ToolCollection = tools,
-        };
-
-        McpServer server = McpServer.Create(
-            serverTransport,
-            serverOptions,
-            NullLoggerFactory.Instance,
-            EmptyServiceProvider.Instance);
-
-        CancellationTokenSource cts = new();
-        Task serverLoop = Task.Run(() => server.RunAsync(cts.Token), cts.Token);
-
-        StreamClientTransport clientTransport = new(
-            clientWriteStream,
-            clientReadStream,
-            NullLoggerFactory.Instance);
-
-        McpClient client = await McpClient.CreateAsync(
-            clientTransport,
-            clientOptions: null,
-            NullLoggerFactory.Instance,
-            cancellationToken).ConfigureAwait(false);
-
-        return new InMemoryMcpServerFixture(server, client, serverLoop, cts);
-    }
-
-    public async ValueTask DisposeAsync()
-    {
-        try
-        {
-            await this.Client.DisposeAsync().ConfigureAwait(false);
-        }
-        catch
-        {
-            // Best effort.
-        }
-
-        this._cts.Cancel();
-
-        try
-        {
-            await this._serverLoop.ConfigureAwait(false);
-        }
-        catch (OperationCanceledException)
-        {
-            // Expected.
-        }
-        catch
-        {
-            // Best effort.
-        }
-
-        try
-        {
-            await this._server.DisposeAsync().ConfigureAwait(false);
-        }
-        catch
-        {
-            // Best effort.
-        }
-
-        this._cts.Dispose();
-    }
-}
@@ -1,55 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Linq;
-using System.Threading.Tasks;
-using FluentAssertions;
-using Microsoft.Extensions.AI;
-using ModelContextProtocol.Protocol;
-using ModelContextProtocol.Server;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-public class ListAgentToolsWithTaskSupportTests
-{
-    [Fact]
-    public async Task ListAgentToolsWithTaskSupport_WrapsTaskCapableTools_LeavesOthersAsIsAsync()
-    {
-        // Arrange
-        McpServerPrimitiveCollection<McpServerTool> tools = [
-            TestTools.Create("opt", ToolTaskSupport.Optional, () => "opt-result"),
-            TestTools.Create("req", ToolTaskSupport.Required, () => "req-result"),
-            TestTools.Create("forb", ToolTaskSupport.Forbidden, () => "forb-result"),
-            TestTools.Create("none", taskSupport: null, () => "none-result"),
-        ];
-        await using InMemoryMcpServerFixture fixture = await InMemoryMcpServerFixture.CreateAsync(tools);
-
-        // Act
-        var result = await fixture.Client.ListAgentToolsWithTaskSupportAsync();
-
-        // Assert
-        result.Should().HaveCount(4);
-        AIFunction opt = result.Single(f => f.Name == "opt");
-        AIFunction req = result.Single(f => f.Name == "req");
-        AIFunction forb = result.Single(f => f.Name == "forb");
-        AIFunction none = result.Single(f => f.Name == "none");
-
-        req.Should().BeOfType<TaskAwareMcpClientAIFunction>("Required tools must be wrapped");
-        opt.Should().NotBeOfType<TaskAwareMcpClientAIFunction>("Optional tools must not be wrapped; inline invocation is preserved by default");
-        forb.Should().NotBeOfType<TaskAwareMcpClientAIFunction>("Forbidden tools must not be wrapped");
-        none.Should().NotBeOfType<TaskAwareMcpClientAIFunction>("Tools without execution metadata must not be wrapped");
-    }
-
-    [Fact]
-    public async Task ListAgentToolsWithTaskSupport_ThrowsOnNullClientAsync()
-    {
-        // Arrange
-        ModelContextProtocol.Client.McpClient client = null!;
-
-        // Act
-        Func<Task> act = async () => await client.ListAgentToolsWithTaskSupportAsync();
-
-        // Assert
-        await act.Should().ThrowAsync<ArgumentNullException>();
-    }
-}
@@ -1,19 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using FluentAssertions;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-public class McpTaskOptionsTests
-{
-    [Fact]
-    public void Defaults_AreSane()
-    {
-        // Act
-        McpTaskOptions options = new();
-
-        // Assert
-        options.DefaultTimeToLive.Should().BeNull();
-        options.CancelRemoteTaskOnLocalCancellation.Should().BeTrue();
-    }
-}
@@ -1,18 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFrameworks>$(TargetFrameworksCore)</TargetFrameworks>
-    <NoWarn>$(NoWarn);MCPEXP001</NoWarn>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="FluentAssertions" />
-    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" />
-    <PackageReference Include="ModelContextProtocol" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <ProjectReference Include="..\..\src\Microsoft.Agents.AI.Mcp\Microsoft.Agents.AI.Mcp.csproj" />
-  </ItemGroup>
-
-</Project>
@@ -1,159 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using System.Linq;
-using System.Text.Json;
-using System.Threading;
-using System.Threading.Tasks;
-using FluentAssertions;
-using Microsoft.Extensions.AI;
-using ModelContextProtocol.Protocol;
-using ModelContextProtocol.Server;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-public class TaskAwareMcpClientAIFunctionTests
-{
-    [Fact]
-    public async Task InvokeAsync_RequiredTool_HappyPath_ReturnsResultAsync()
-    {
-        // Arrange
-        McpServerPrimitiveCollection<McpServerTool> tools = [
-            TestTools.Create("req", ToolTaskSupport.Required, () => "required-result"),
-        ];
-        await using InMemoryMcpServerFixture fixture = await InMemoryMcpServerFixture.CreateAsync(tools);
-        var result = await fixture.Client.ListAgentToolsWithTaskSupportAsync();
-        AIFunction req = result.Single(f => f.Name == "req");
-        req.Should().BeOfType<TaskAwareMcpClientAIFunction>();
-
-        // Act
-        object? invokeResult = await req.InvokeAsync(arguments: null, CancellationToken.None);
-
-        // Assert
-        JsonElement payload = invokeResult.Should().BeOfType<JsonElement>().Subject;
-        ExtractTextContent(payload).Should().Be("required-result");
-    }
-
-    [Fact]
-    public async Task InvokeAsync_PropagatesDefaultTimeToLiveAsync()
-    {
-        // Arrange — capture the request meta on the server so we can assert TTL flowed through.
-        TimeSpan? observedTtl = null;
-        McpServerTool tool = McpServerTool.Create(
-            (RequestContext<CallToolRequestParams> ctx) =>
-            {
-                observedTtl = ctx.Params?.Task?.TimeToLive;
-                return "ok";
-            },
-            new McpServerToolCreateOptions
-            {
-                Name = "ttl-tool",
-                Description = "Echoes the requested TTL.",
-                Execution = new ToolExecution { TaskSupport = ToolTaskSupport.Required },
-            });
-        McpServerPrimitiveCollection<McpServerTool> tools = [tool];
-
-        await using InMemoryMcpServerFixture fixture = await InMemoryMcpServerFixture.CreateAsync(tools);
-
-        TimeSpan requestedTtl = TimeSpan.FromMinutes(7);
-        var result = await fixture.Client.ListAgentToolsWithTaskSupportAsync(new McpTaskOptions { DefaultTimeToLive = requestedTtl });
-        AIFunction wrapped = result.Single();
-
-        // Act
-        _ = await wrapped.InvokeAsync(arguments: null, CancellationToken.None);
-
-        // Assert
-        observedTtl.Should().Be(requestedTtl);
-    }
-
-    [Fact]
-    public async Task InvokeAsync_RespectsCancellationAsync()
-    {
-        // Arrange — a tool that never completes until it's cancelled.
-        var serverCancelled = new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
-        McpServerTool tool = McpServerTool.Create(
-            async (CancellationToken ct) =>
-            {
-                try
-                {
-                    await Task.Delay(Timeout.Infinite, ct);
-                }
-                catch (OperationCanceledException)
-                {
-                    serverCancelled.TrySetResult(true);
-                    throw;
-                }
-
-                return "should-not-complete";
-            },
-            new McpServerToolCreateOptions
-            {
-                Name = "blocking",
-                Description = "Blocks indefinitely until cancelled.",
-                Execution = new ToolExecution { TaskSupport = ToolTaskSupport.Required },
-            });
-        McpServerPrimitiveCollection<McpServerTool> tools = [tool];
-
-        await using InMemoryMcpServerFixture fixture = await InMemoryMcpServerFixture.CreateAsync(tools);
-        var result = await fixture.Client.ListAgentToolsWithTaskSupportAsync();
-        AIFunction wrapped = result.Single();
-
-        using CancellationTokenSource cts = new();
-
-        // Act — start the invocation, cancel after a brief delay.
-        Task<object?> invocation = wrapped.InvokeAsync(arguments: null, cts.Token).AsTask();
-        await Task.Delay(200);
-        cts.Cancel();
-
-        // Assert — wrapper observes cancellation and signals server-side cancellation.
-        Func<Task> awaitInvocation = async () => await invocation;
-        await awaitInvocation.Should().ThrowAsync<OperationCanceledException>();
-
-        // Server-side handler should have observed cancellation as a result of the wrapper's
-        // tasks/cancel call (best-effort wait — give the server-loop a few seconds).
-        Task observedTask = serverCancelled.Task;
-        Task completed = await Task.WhenAny(observedTask, Task.Delay(TimeSpan.FromSeconds(5)));
-        completed.Should().BeSameAs(observedTask, "the wrapper should have issued tasks/cancel");
-    }
-
-    [Fact]
-    public async Task InvokeAsync_FailedTask_ThrowsInvalidOperationAsync()
-    {
-        // Arrange — a tool whose handler throws, which the server surfaces as a Failed task.
-        McpServerTool tool = McpServerTool.Create(
-            (Func<string>)(() => throw new InvalidOperationException("simulated tool failure")),
-            new McpServerToolCreateOptions
-            {
-                Name = "boom",
-                Description = "Throws unconditionally.",
-                Execution = new ToolExecution { TaskSupport = ToolTaskSupport.Required },
-            });
-        McpServerPrimitiveCollection<McpServerTool> tools = [tool];
-
-        await using InMemoryMcpServerFixture fixture = await InMemoryMcpServerFixture.CreateAsync(tools);
-        var result = await fixture.Client.ListAgentToolsWithTaskSupportAsync();
-        AIFunction wrapped = result.Single();
-
-        // Act
-        Func<Task> act = async () => await wrapped.InvokeAsync(arguments: null, CancellationToken.None);
-
-        // Assert — Phase 1 surfaces non-Completed terminal states as InvalidOperationException
-        // carrying the server's StatusMessage. (See PollAndRetrieveResultAsync.)
-        await act.Should().ThrowAsync<Exception>().Where(ex =>
-            ex is InvalidOperationException
-            || ex.GetType().FullName == "ModelContextProtocol.McpException");
-    }
-
-    /// <summary>
-    /// Extracts the first text-content block from a serialized <c>CallToolResult</c>
-    /// (the JSON shape returned by the wrapper and by <c>McpClientTool.InvokeAsync</c>).
-    /// </summary>
-    private static string ExtractTextContent(JsonElement payload)
-    {
-        payload.ValueKind.Should().Be(JsonValueKind.Object);
-        JsonElement content = payload.GetProperty("content");
-        content.ValueKind.Should().Be(JsonValueKind.Array);
-        JsonElement firstBlock = content.EnumerateArray().First();
-        return firstBlock.GetProperty("text").GetString()!;
-    }
-}
@@ -1,30 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System;
-using ModelContextProtocol.Protocol;
-using ModelContextProtocol.Server;
-
-namespace Microsoft.Agents.AI.Mcp.UnitTests;
-
-/// <summary>
-/// Helpers to create <see cref="McpServerTool"/> instances with a specific
-/// <see cref="ToolTaskSupport"/> level for in-memory fixtures.
-/// </summary>
-internal static class TestTools
-{
-    public static McpServerTool Create(string name, ToolTaskSupport? taskSupport, Delegate handler)
-    {
-        McpServerToolCreateOptions options = new()
-        {
-            Name = name,
-            Description = $"Test tool {name}.",
-        };
-
-        if (taskSupport is ToolTaskSupport ts)
-        {
-            options.Execution = new ToolExecution { TaskSupport = ts };
-        }
-
-        return McpServerTool.Create(handler, options);
-    }
-}
@@ -6,7 +6,6 @@ using System.Reflection;
 using System.Runtime.InteropServices;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.AI;

 namespace Microsoft.Agents.AI.Tools.Shell.UnitTests;

@@ -227,8 +226,6 @@ public sealed class ShellEnvironmentProviderTests
        public override Task InitializeAsync(CancellationToken cancellationToken = default) => Task.CompletedTask;
        public override Task<ShellResult> RunAsync(string command, CancellationToken cancellationToken = default) =>
            Task.FromResult(this.Responses.Dequeue());
-        public override AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true) =>
-            throw new NotSupportedException();
        public override ValueTask DisposeAsync() => default;
    }

@@ -283,8 +280,6 @@ public sealed class ShellEnvironmentProviderTests
        public override Task InitializeAsync(CancellationToken cancellationToken = default) => Task.CompletedTask;
        public override Task<ShellResult> RunAsync(string command, CancellationToken cancellationToken = default) =>
            Task.FromResult(this._factory(cancellationToken));
-        public override AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true) =>
-            throw new NotSupportedException();
        public override ValueTask DisposeAsync() => default;
    }

@@ -377,8 +372,6 @@ public sealed class ShellEnvironmentProviderTests
            this.RunCount++;
            return Task.FromResult(this.NextResult);
        }
-        public override AIFunction AsAIFunction(string name = "run_shell", string? description = null, bool requireApproval = true) =>
-            throw new NotSupportedException();
        public override ValueTask DisposeAsync() => default;
    }
 }
@@ -1,139 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.Agents.AI.Workflows.Declarative.Extensions;
-using Microsoft.Agents.AI.Workflows.Declarative.Kit;
-using Microsoft.Agents.AI.Workflows.Declarative.PowerFx;
-using Microsoft.Agents.AI.Workflows.Declarative.UnitTests.ObjectModel;
-using Microsoft.Agents.ObjectModel;
-using Microsoft.Extensions.AI;
-using Microsoft.PowerFx.Types;
-using Moq;
-
-namespace Microsoft.Agents.AI.Workflows.Declarative.UnitTests.Extensions;
-
-/// <summary>
-/// Tests for <see cref="AgentProviderExtensions.InvokeAgentAsync"/>.
-/// </summary>
-public sealed class AgentProviderExtensionsTest(ITestOutputHelper output) : WorkflowActionExecutorTest(output)
-{
-    private const string WorkflowConversationId = "workflow-conv-id";
-    private const string AgentName = "test-agent";
-
-    [Fact]
-    public Task AutoSendFalseOnWorkflowConversationSuppressesResponseEventsAsync() =>
-        this.RunAsync(autoSend: false, conversationId: WorkflowConversationId, expectResponseEvents: false);
-
-    [Fact]
-    public Task AutoSendTrueOnWorkflowConversationEmitsResponseEventsAsync() =>
-        this.RunAsync(autoSend: true, conversationId: WorkflowConversationId, expectResponseEvents: true);
-
-    [Fact]
-    public Task AutoSendFalseOnExternalConversationSuppressesResponseEventsAsync() =>
-        this.RunAsync(autoSend: false, conversationId: "other-conv-id", expectResponseEvents: false);
-
-    [Fact]
-    public Task AutoSendTrueOnExternalConversationEmitsResponseEventsAndCopiesMessagesAsync() =>
-        this.RunAsync(
-            autoSend: true,
-            conversationId: "other-conv-id",
-            expectResponseEvents: true,
-            expectCrossConversationCopy: true);
-
-    private async Task RunAsync(
-        bool autoSend,
-        string conversationId,
-        bool expectResponseEvents,
-        bool expectCrossConversationCopy = false)
-    {
-        // Arrange: seed the workflow conversation id so IsWorkflowConversation can recognize it.
-        this.State.Set(
-            SystemScope.Names.ConversationId,
-            FormulaValue.New(WorkflowConversationId),
-            VariableScopeNames.System);
-
-        MockAgentProvider mockProvider = new();
-        AgentResponseUpdate[] updates =
-        [
-            new(ChatRole.Assistant, "hello "),
-            new(ChatRole.Assistant, "world"),
-        ];
-        mockProvider
-            .Setup(p => p.InvokeAgentAsync(
-                AgentName,
-                It.IsAny<string?>(),
-                It.IsAny<string?>(),
-                It.IsAny<IEnumerable<ChatMessage>?>(),
-                It.IsAny<IDictionary<string, object?>?>(),
-                It.IsAny<CancellationToken>()))
-            .Returns(ToAsyncEnumerableAsync(updates));
-
-        List<(string ConversationId, ChatMessage Message)> copiedMessages = [];
-        mockProvider
-            .Setup(p => p.CreateMessageAsync(
-                It.IsAny<string>(),
-                It.IsAny<ChatMessage>(),
-                It.IsAny<CancellationToken>()))
-            .Returns<string, ChatMessage, CancellationToken>(
-                (convId, msg, _) =>
-                {
-                    copiedMessages.Add((convId, msg));
-                    return Task.FromResult(msg);
-                });
-
-        string actionId = this.CreateActionId().Value;
-
-        // Act
-        WorkflowEvent[] events =
-            await this.ExecuteAsync(
-                actionId,
-                async (IWorkflowContext context, ActionExecutorResult _, CancellationToken cancellationToken) =>
-                {
-                    await mockProvider.Object.InvokeAgentAsync(
-                        actionId,
-                        context,
-                        AgentName,
-                        conversationId,
-                        autoSend,
-                        cancellationToken: cancellationToken).ConfigureAwait(false);
-                });
-
-        // Assert
-        int updateEventCount = events.OfType<AgentResponseUpdateEvent>().Count();
-        int responseEventCount = events.OfType<AgentResponseEvent>().Count();
-
-        if (expectResponseEvents)
-        {
-            Assert.Equal(updates.Length, updateEventCount);
-            Assert.Equal(1, responseEventCount);
-        }
-        else
-        {
-            Assert.Equal(0, updateEventCount);
-            Assert.Equal(0, responseEventCount);
-        }
-
-        if (expectCrossConversationCopy)
-        {
-            Assert.NotEmpty(copiedMessages);
-            Assert.All(copiedMessages, c => Assert.Equal(WorkflowConversationId, c.ConversationId));
-        }
-        else
-        {
-            Assert.Empty(copiedMessages);
-        }
-    }
-
-    private static async IAsyncEnumerable<AgentResponseUpdate> ToAsyncEnumerableAsync(IEnumerable<AgentResponseUpdate> updates)
-    {
-        foreach (AgentResponseUpdate update in updates)
-        {
-            yield return update;
-        }
-
-        await Task.CompletedTask;
-    }
-}
@@ -7,22 +7,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 ## [Unreleased]

-## [1.6.0] - 2026-05-21
-
-### Added
- **agent-framework-core**: Shell tool with support for local and Docker execution ([#5664](https://github.com/microsoft/agent-framework/pull/5664))
- **agent-framework-monty**: New Monty-backed CodeAct provider package ([#5915](https://github.com/microsoft/agent-framework/pull/5915))
- **agent-framework-foundry**: Add experimental hosted tool factories on `FoundryChatClient` ([#5958](https://github.com/microsoft/agent-framework/pull/5958))
- **agent-framework-foundry**: Include tool definitions for Foundry agent evals ([#5974](https://github.com/microsoft/agent-framework/pull/5974))
- **agent-framework-a2a**: Use non-streaming transport and `return_immediately` for background ops ([#5963](https://github.com/microsoft/agent-framework/pull/5963))
-
-### Changed
- **agent-framework-core**, **agent-framework-foundry**: [BREAKING] Enable instrumentation by default ([#5865](https://github.com/microsoft/agent-framework/pull/5865))
- **agent-framework-foundry**: Show more authentication methods in Foundry Toolbox MCP ([#5719](https://github.com/microsoft/agent-framework/pull/5719))
-
-### Fixed
- **agent-framework-core**: Skip MCP prompt loading when unsupported ([#5370](https://github.com/microsoft/agent-framework/pull/5370))
-
 ## [1.5.0] - 2026-05-19

 ### Added
@@ -1104,8 +1088,7 @@ 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-1.6.0...HEAD
-[1.6.0]: https://github.com/microsoft/agent-framework/compare/python-1.5.0...python-1.6.0
+[Unreleased]: https://github.com/microsoft/agent-framework/compare/python-1.5.0...HEAD
 [1.5.0]: https://github.com/microsoft/agent-framework/compare/python-1.4.0...python-1.5.0
 [1.4.0]: https://github.com/microsoft/agent-framework/compare/python-1.3.0...python-1.4.0
 [1.3.0]: https://github.com/microsoft/agent-framework/compare/python-1.2.2...python-1.3.0
@@ -129,7 +129,6 @@ class A2AAgent(AgentTelemetryLayer, BaseAgent):
        self._timeout_config = self._create_timeout_config(timeout)
        if client is not None:
            self.client = client
-            self._non_streaming_client: Client | None = None
            self._close_http_client = True
            return
        if agent_card is None:
@@ -145,30 +144,17 @@ class A2AAgent(AgentTelemetryLayer, BaseAgent):
            self._http_client = http_client  # Store for cleanup
            self._close_http_client = True

+        # Create A2A client using factory
+        config = ClientConfig(
+            httpx_client=http_client,
+            supported_protocol_bindings=["JSONRPC"],
+        )
+        factory = ClientFactory(config)
        interceptors = [auth_interceptor] if auth_interceptor is not None else None

-        # Create streaming client (SSE transport for stream=True)
-        streaming_config = ClientConfig(
-            httpx_client=http_client,
-            streaming=True,
-            supported_protocol_bindings=["JSONRPC"],
-        )
-        # Create non-streaming client (single request/response for stream=False)
-        non_streaming_config = ClientConfig(
-            httpx_client=http_client,
-            streaming=False,
-            supported_protocol_bindings=["JSONRPC"],
-        )
-        streaming_factory = ClientFactory(streaming_config)
-        non_streaming_factory = ClientFactory(non_streaming_config)
-
        # Attempt transport negotiation with the provided agent card
        try:
-            self.client = streaming_factory.create(agent_card, interceptors=interceptors)  # type: ignore
-            self._non_streaming_client = non_streaming_factory.create(
-                agent_card,
-                interceptors=interceptors,  # type: ignore
-            )
+            self.client = factory.create(agent_card, interceptors=interceptors)  # type: ignore
        except Exception as transport_error:
            # Transport negotiation failed - fall back to minimal agent card with JSONRPC
            fallback_url = agent_card.supported_interfaces[0].url if agent_card.supported_interfaces else url
@@ -180,11 +166,7 @@ class A2AAgent(AgentTelemetryLayer, BaseAgent):
                ) from transport_error
            fallback_card = minimal_agent_card(fallback_url, ["JSONRPC"])
            try:
-                self.client = streaming_factory.create(fallback_card, interceptors=interceptors)  # type: ignore
-                self._non_streaming_client = non_streaming_factory.create(
-                    fallback_card,
-                    interceptors=interceptors,  # type: ignore
-                )
+                self.client = factory.create(fallback_card, interceptors=interceptors)  # type: ignore
            except Exception as fallback_error:
                raise RuntimeError(
                    f"A2A transport negotiation failed. "
@@ -300,13 +282,6 @@ class A2AAgent(AgentTelemetryLayer, BaseAgent):
        del function_invocation_kwargs, client_kwargs, kwargs
        normalized_messages = normalize_messages(messages)

-        # Use non-streaming transport for non-streaming calls when available.
-        # This sends a single HTTP request/response instead of opening an SSE
-        # connection, matching the protocol's intent for synchronous operations.
-        active_client = (
-            self._non_streaming_client if (not stream and self._non_streaming_client is not None) else self.client
-        )
-
        if continuation_token is not None:
            a2a_stream: AsyncIterable[A2AStreamItem] = self.client.subscribe(
                SubscribeToTaskRequest(id=continuation_token["task_id"])
@@ -318,11 +293,7 @@ class A2AAgent(AgentTelemetryLayer, BaseAgent):
                normalized_messages[-1],
                context_id=session.service_session_id if session else None,
            )
-            request = SendMessageRequest(message=a2a_message)
-            if background and not stream:
-                # return_immediately only applies to non-streaming (message/send)
-                request.configuration.return_immediately = True
-            a2a_stream = active_client.send_message(request)
+            a2a_stream = self.client.send_message(SendMessageRequest(message=a2a_message))

        provider_session = session
        if provider_session is None and self.context_providers:
@@ -4,7 +4,7 @@ description = "A2A integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "a2a-sdk>=1.0.0,<2",
 ]

@@ -44,7 +44,6 @@ class MockA2AClient:
        self.subscribe_responses: list[StreamResponse] = []
        self.get_task_response: Task | None = None
        self.last_message: Any = None
-        self.last_request: Any = None

    def add_message_response(self, message_id: str, text: str, role: str = "agent") -> None:
        """Add a mock Message response."""
@@ -92,7 +91,6 @@ class MockA2AClient:

    async def send_message(self, request: Any) -> AsyncIterator[StreamResponse]:
        """Mock send_message method that yields responses."""
-        self.last_request = request
        self.last_message = getattr(request, "message", request)
        self.call_count += 1

@@ -747,96 +745,6 @@ async def test_working_task_no_token_without_background(a2a_agent: A2AAgent, moc
    assert response.continuation_token is None


-async def test_background_sets_return_immediately_on_request(
-    a2a_agent: A2AAgent, mock_a2a_client: MockA2AClient
-) -> None:
-    """Test that background=True sets return_immediately=True on SendMessageRequest configuration."""
-    mock_a2a_client.add_in_progress_task_response("task-bg", state=TaskState.TASK_STATE_WORKING)
-
-    await a2a_agent.run("Background task", background=True)
-
-    assert mock_a2a_client.last_request.configuration.return_immediately is True
-
-
-async def test_foreground_does_not_set_return_immediately(
-    a2a_agent: A2AAgent, mock_a2a_client: MockA2AClient
-) -> None:
-    """Test that background=False (default) does not set configuration on SendMessageRequest."""
-    mock_a2a_client.add_task_response("task-fg2", [{"id": "art-1", "content": "Done"}])
-
-    await a2a_agent.run("Foreground task")
-
-    assert mock_a2a_client.last_request.HasField("configuration") is False
-
-
-async def test_streaming_background_does_not_set_return_immediately(
-    a2a_agent: A2AAgent, mock_a2a_client: MockA2AClient
-) -> None:
-    """Test that background=True with stream=True does not set return_immediately.
-
-    Per A2A spec, return_immediately only applies to non-streaming (message/send).
-    """
-    mock_a2a_client.add_task_response("task-sb", [{"id": "art-1", "content": "Streaming bg"}])
-
-    updates: list[AgentResponseUpdate] = []
-    async for update in a2a_agent.run("Stream background", stream=True, background=True):
-        updates.append(update)
-
-    assert mock_a2a_client.last_request.HasField("configuration") is False
-
-
-async def test_non_streaming_run_uses_non_streaming_client() -> None:
-    """Test that stream=False uses the non-streaming client when available."""
-    streaming_client = MockA2AClient()
-    non_streaming_client = MockA2AClient()
-    non_streaming_client.add_task_response("task-ns", [{"id": "art-1", "content": "Non-streaming result"}])
-
-    agent = A2AAgent(name="Test Agent", id="test-ns", client=streaming_client, http_client=None)
-    agent._non_streaming_client = non_streaming_client  # type: ignore[assignment]
-
-    response = await agent.run("Hello")
-
-    # Non-streaming client should have been called
-    assert non_streaming_client.call_count == 1
-    assert streaming_client.call_count == 0
-    assert response.messages[0].text == "Non-streaming result"
-    assert non_streaming_client.last_request.HasField("configuration") is False
-
-
-async def test_streaming_run_uses_streaming_client() -> None:
-    """Test that stream=True always uses the streaming client."""
-    streaming_client = MockA2AClient()
-    non_streaming_client = MockA2AClient()
-    streaming_client.add_task_response("task-s", [{"id": "art-1", "content": "Streaming result"}])
-
-    agent = A2AAgent(name="Test Agent", id="test-s", client=streaming_client, http_client=None)
-    agent._non_streaming_client = non_streaming_client  # type: ignore[assignment]
-
-    updates: list[AgentResponseUpdate] = []
-    async for update in agent.run("Hello", stream=True):
-        updates.append(update)
-
-    # Streaming client should have been called
-    assert streaming_client.call_count == 1
-    assert non_streaming_client.call_count == 0
-    assert updates[0].contents[0].text == "Streaming result"
-
-
-async def test_non_streaming_client_fallback_when_not_available(
-    a2a_agent: A2AAgent, mock_a2a_client: MockA2AClient
-) -> None:
-    """Test that stream=False falls back to streaming client when non-streaming client is unavailable."""
-    mock_a2a_client.add_task_response("task-fb", [{"id": "art-1", "content": "Fallback result"}])
-
-    # a2a_agent is created with client= param so _non_streaming_client is None
-    assert a2a_agent._non_streaming_client is None
-
-    response = await a2a_agent.run("Hello")
-
-    assert mock_a2a_client.call_count == 1
-    assert response.messages[0].text == "Fallback result"
-
-
 async def test_completed_task_has_no_continuation_token(a2a_agent: A2AAgent, mock_a2a_client: MockA2AClient) -> None:
    """Test that a completed task does not set a continuation token."""
    mock_a2a_client.add_task_response("task-done", [{"id": "art-1", "content": "Result"}])
@@ -1,6 +1,6 @@
 [project]
 name = "agent-framework-ag-ui"
-version = "1.0.0rc3"
+version = "1.0.0rc2"
 description = "AG-UI protocol integration for Agent Framework"
 readme = "README.md"
 license-files = ["LICENSE"]
@@ -22,7 +22,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "ag-ui-protocol>=0.1.16,<0.2",
    "fastapi>=0.115.0,<0.133.1",
    "uvicorn[standard]>=0.30.0,<1"
@@ -4,7 +4,7 @@ description = "Anthropic integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "anthropic>=0.80.0,<0.80.1",
 ]

@@ -4,7 +4,7 @@ description = "Azure AI Search integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "azure-search-documents>=11.7.0b2,<11.7.0b3",
 ]

@@ -4,7 +4,7 @@ description = "Azure Content Understanding integration for Microsoft Agent Frame
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com" }]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0a260521"
+version = "1.0.0a260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,8 +23,8 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
-    "agent-framework-foundry>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
+    "agent-framework-foundry>=1.5.0,<2",
    "azure-ai-contentunderstanding>=1.0.1,<1.1",
    "aiohttp>=3.9,<4",
    "filetype>=1.2,<2",
@@ -4,7 +4,7 @@ description = "Azure Cosmos DB history provider integration for Microsoft Agent
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "azure-cosmos>=4.3.0,<5",
 ]

@@ -4,7 +4,7 @@ description = "Azure Functions integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -22,8 +22,8 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
-    "agent-framework-durabletask>=1.0.0b260521,<2",
+    "agent-framework-core>=1.5.0,<2",
+    "agent-framework-durabletask>=1.0.0b260519,<2",
    "azure-functions>=1.24.0,<2",
    "azure-functions-durable>=1.3.1,<2",
 ]
@@ -4,7 +4,7 @@ description = "Amazon Bedrock integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "boto3>=1.35.0,<2.0.0",
    "botocore>=1.35.0,<2.0.0",
 ]
@@ -4,7 +4,7 @@ description = "OpenAI ChatKit integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -22,7 +22,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "openai-chatkit>=1.4.1,<2.0.0",
 ]

@@ -4,7 +4,7 @@ description = "Claude Agent SDK integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "claude-agent-sdk>=0.1.36,<0.1.49",
 ]

@@ -4,7 +4,7 @@ description = "Copilot Studio integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260521"
+version = "1.0.0b260519"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
  "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.6.0,<2",
+    "agent-framework-core>=1.5.0,<2",
    "microsoft-agents-copilotstudio-client>=0.3.1,<0.3.2",
 ]

@@ -2,14 +2,10 @@

 from __future__ import annotations

-import abc
 import asyncio.coroutines
-import contextlib
 import functools
 import inspect
-import os
 import sys
-import typing
 import warnings
 from collections.abc import Callable
 from enum import Enum
@@ -53,8 +49,6 @@ class ExperimentalFeature(str, Enum):
    EVALS = "EVALS"
    FILE_HISTORY = "FILE_HISTORY"
    FIDES = "FIDES"
-    FOUNDRY_TOOLS = "FOUNDRY_TOOLS"
-    FOUNDRY_PREVIEW_TOOLS = "FOUNDRY_PREVIEW_TOOLS"
    FUNCTIONAL_WORKFLOWS = "FUNCTIONAL_WORKFLOWS"
    HARNESS = "HARNESS"
    SKILLS = "SKILLS"
@@ -79,51 +73,6 @@ class ExperimentalWarning(FeatureStageWarning):
    """Warning emitted when an experimental API is used."""


-# Sentinel attribute used to detect (and reuse) a formatter we've already
-# installed. This lets the install be idempotent across re-imports / reloads
-# and keeps a stable reference to the previous formatter for testing or
-# external restoration via ``warnings.formatwarning = original``.
-_FEATURE_STAGE_FORMATTER_MARKER = "__feature_stage_formatter__"
-
-
-def _install_feature_stage_formatter() -> None:
-    """Install a single-line formatter for FeatureStageWarning categories.
-
-    The stdlib default formatter emits two lines (header + source snippet)
-    which is noisy for our warnings — the offending class/function name is
-    already in the message, so a one-line ``file:lineno: Category: message``
-    is enough. Other warning categories are delegated to the previous
-    formatter so we never change behaviour for unrelated warnings.
-
-    The install is idempotent: if a formatter installed by this module is
-    already in place, we leave it alone so re-imports (and any third-party
-    formatter wrapped on top of ours) don't get wrapped multiple times.
-    """
-    current = warnings.formatwarning
-    if getattr(current, _FEATURE_STAGE_FORMATTER_MARKER, False):
-        return
-
-    def _formatwarning(
-        message: Warning | str,
-        category: type[Warning],
-        filename: str,
-        lineno: int,
-        line: str | None = None,
-    ) -> str:
-        if issubclass(category, FeatureStageWarning):
-            return f"{filename}:{lineno}: {category.__name__}: {message}\n"
-        return current(message, category, filename, lineno, line)
-
-    setattr(_formatwarning, _FEATURE_STAGE_FORMATTER_MARKER, True)
-    # Keep a reference to the wrapped formatter so callers (tests, embedders)
-    # can restore the previous behaviour if they need to.
-    _formatwarning.__wrapped__ = current  # type: ignore[attr-defined]
-    warnings.formatwarning = _formatwarning
-
-
-_install_feature_stage_formatter()
-
-
 def _normalize_feature_id(feature_id: str | Enum) -> str:
    return str(feature_id.value if isinstance(feature_id, Enum) else feature_id)

@@ -158,91 +107,23 @@ def _set_feature_stage_metadata(obj: Any, *, stage: FeatureStageName, feature_id
    setattr(obj, _FEATURE_ID_ATTR, feature_id)


-_INTERNAL_FRAME_FILE = os.path.normcase(__file__)
-# Module names whose frames we never want to surface as the caller. ``abc`` is
-# the big one (its ``__new__`` shows up as ``<frozen abc>:106`` for ABC-driven
-# subclass creation on modern CPython, so we cannot rely on filename matching).
-# ``functools``/``typing``/``contextlib`` are added because they often wrap our
-# decorators or appear in the metaclass call path.
-_INTERNAL_FRAME_MODULES: frozenset[str] = frozenset({
-    abc.__name__,
-    functools.__name__,
-    typing.__name__,
-    contextlib.__name__,
-})
-
-
-def _is_internal_frame(frame: Any) -> bool:
-    if os.path.normcase(frame.f_code.co_filename) == _INTERNAL_FRAME_FILE:
-        return True
-    module_name = frame.f_globals.get("__name__", "")
-    if module_name in _INTERNAL_FRAME_MODULES:
-        return True
-    # Submodules of the skipped stdlib packages (``typing.ext``, ``functools``
-    # wrappers under ``concurrent.futures._base``, etc.) are also wrappers we
-    # don't want to surface.
-    return any(module_name.startswith(prefix + ".") for prefix in _INTERNAL_FRAME_MODULES)
-
-
-def _resolve_user_frame() -> tuple[str, int, str] | None:
-    """Resolve the user frame that triggered an experimental warning.
-
-    Walk the stack and return ``(filename, lineno, module_name)`` for the first
-    frame outside this module and the wrapping/metaclass machinery.
-
-    Returns ``None`` if no such frame is found; callers fall back to plain
-    ``warnings.warn`` with a fixed stacklevel.
-    """
-    # Frame objects participate in reference cycles (``frame -> f_locals ->
-    # frame``) and can delay GC if held implicitly. Capture the user frame's
-    # data into plain values inside the try, and explicitly delete the frame
-    # references in finally so we never leak frames across this call. This
-    # follows CPython's own guidance for code that uses ``inspect.currentframe``.
-    frame = inspect.currentframe()
-    candidate: Any = None
-    try:
-        if frame is None:
-            return None
-        # Skip _resolve_user_frame itself + the warn helper that called it.
-        candidate = frame.f_back.f_back if frame.f_back and frame.f_back.f_back else None
-        while candidate is not None:
-            if not _is_internal_frame(candidate):
-                return (
-                    candidate.f_code.co_filename,
-                    candidate.f_lineno,
-                    candidate.f_globals.get("__name__", "<unknown>"),
-                )
-            candidate = candidate.f_back
-        return None
-    finally:
-        del frame, candidate
-
-
 def _warn_on_feature_use(
    *,
    stage: FeatureStageName,
    feature_id: str,
    object_name: str,
    category: type[Warning],
+    stacklevel: int,
 ) -> None:
    warning_key = (category, feature_id)
    if warning_key in _WARNED_FEATURES:
        return

-    message = _build_stage_warning_message(stage=stage, feature_id=feature_id, object_name=object_name)
-    user_frame = _resolve_user_frame()
-    if user_frame is None:
-        # Last-resort fallback: emit at the immediate caller of this helper.
-        warnings.warn(message, category=category, stacklevel=2)
-    else:
-        filename, lineno, module = user_frame
-        warnings.warn_explicit(
-            message,
-            category=category,
-            filename=filename,
-            lineno=lineno,
-            module=module,
-        )
+    warnings.warn(
+        _build_stage_warning_message(stage=stage, feature_id=feature_id, object_name=object_name),
+        category=category,
+        stacklevel=stacklevel,
+    )
    _WARNED_FEATURES.add(warning_key)


@@ -267,6 +148,7 @@ def _add_runtime_warning(
                    feature_id=feature_id,
                    object_name=object_name,
                    category=category,
+                    stacklevel=3,
                )
            if original_new is not object.__new__:
                return original_new(cls, *args, **kwargs)
@@ -287,6 +169,7 @@ def _add_runtime_warning(
                    feature_id=feature_id,
                    object_name=object_name,
                    category=category,
+                    stacklevel=3,
                )
                return original_init_subclass_func(*args, **kwargs)

@@ -300,6 +183,7 @@ def _add_runtime_warning(
                    feature_id=feature_id,
                    object_name=object_name,
                    category=category,
+                    stacklevel=3,
                )
                return original_init_subclass(*args, **kwargs)

@@ -314,6 +198,7 @@ def _add_runtime_warning(
            feature_id=feature_id,
            object_name=object_name,
            category=category,
+            stacklevel=3,
        )
        return obj(*args, **kwargs)

--- a/Show More
+++ b/Show More