Python: Add MCP-based skills discovery (McpSkillsSource) (#6169)

* Add MCP-based skills discovery (McpSkill, McpSkillsSource, McpSkillResource) Implement Agent Skills discovery over MCP following the SEP-2640 convention: - McpSkillsSource: reads skill://index.json to discover skills served by an MCP server - McpSkill: lazily fetches SKILL.md content via resources/read on demand - McpSkillResource: wraps MCP resource results (text and binary) - Path traversal protection in get_resource for defense in depth - Samples for Foundry Toolbox and standalone MCP skills server - Comprehensive unit tests (514 lines) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Address PR review comments: rename to MCP* convention, fix error handling and samples - Rename McpSkill/McpSkillResource/McpSkillsSource to MCPSkill/MCPSkillResource/MCPSkillsSource - Add data-URI prefix stripping for blob resource decoding - Let non-McpError exceptions propagate from get_resource() - Fix contradictory test comment - Use interactive input() in mcp_based_skill sample - Remove misleading sample output block Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Restore debug logging for McpError in get_resource() Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Use AzureCliCredential in Foundry toolbox skills sample for consistency Replace DefaultAzureCredential with AzureCliCredential to match the credential convention used in all other samples. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Use MCPStreamableHTTPTool in MCP skills sample Replace raw mcp library imports (ClientSession, streamable_http_client) with the framework's MCPStreamableHTTPTool to keep MCP server connections consistent regardless of whether skills are enabled. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Branch on McpError.error.code so only not-found errors return empty Previously _try_read_index() and get_resource() swallowed every McpError as 'no skills available', making auth failures, server crashes, and connection drops indistinguishable from a server that simply has no skills. Now only two codes are treated as not-found: - -32002 (MCP-spec Resource not found) - -32601 (METHOD_NOT_FOUND — server lacks resources/read) All other McpError codes and non-McpError exceptions propagate with a warning log, surfacing real failures visibly. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add tests for non-McpError and non-not-found error propagation in MCP skills Cover the re-raise branch in MCPSkill.get_resource for plain ConnectionError/TimeoutError, the generic McpError (code 0) propagation on get_resource, and TimeoutError propagation in _try_read_index. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Revert "Use MCPStreamableHTTPTool in MCP skills sample" This reverts commit f31ed0ded9. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Introduce MCP_SKILLS experimental feature for MCP skill classes Add a separate MCP_SKILLS feature ID to ExperimentalFeature enum and use it for MCPSkillResource, MCPSkill, and MCPSkillsSource, since their promotion timeline is partly outside of our control. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
2026-06-16 21:04:09 +08:00 · 2026-06-03 18:09:50 +00:00
parent a982428916
commit c6951c21f6
9 changed files with 1333 additions and 0 deletions
@@ -27,6 +27,7 @@ This folder contains Azure AI Foundry and Foundry Local samples for Agent Framew
 | [`foundry_chat_client_with_local_mcp.py`](foundry_chat_client_with_local_mcp.py) | Foundry Chat Client with local MCP |
 | [`foundry_chat_client_with_session.py`](foundry_chat_client_with_session.py) | Foundry Chat Client with session management |
 | [`foundry_chat_client_with_toolbox.py`](foundry_chat_client_with_toolbox.py) | Foundry Chat Client connected to a toolbox via its MCP endpoint using `MCPStreamableHTTPTool` |
+| [`foundry_chat_client_with_toolbox_skills.py`](foundry_chat_client_with_toolbox_skills.py) | Foundry Chat Client that discovers MCP-based skills from a Foundry Toolbox endpoint via `MCPSkillsSource` (uses an Azure AD bearer token and the toolbox preview header) |

 ## FoundryLocalClient Samples

@@ -0,0 +1,87 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+import asyncio
+import os
+from collections.abc import Generator
+
+import httpx
+from agent_framework import Agent, MCPSkillsSource, SkillsProvider
+from agent_framework.foundry import FoundryChatClient
+from azure.core.credentials import TokenCredential
+from azure.identity import AzureCliCredential, get_bearer_token_provider
+from dotenv import load_dotenv
+from mcp.client.session import ClientSession
+from mcp.client.streamable_http import streamable_http_client
+
+# Load environment variables from .env file
+load_dotenv()
+
+"""
+Foundry Chat Client with Toolbox-Hosted Skills
+
+Discover Agent Skills served by a Microsoft Foundry Toolbox MCP endpoint
+and inject them into a ``FoundryChatClient`` agent via ``MCPSkillsSource``.
+The toolbox's discovery document (``skill://index.json``) is read once at
+startup; SKILL.md bodies are fetched on demand as the agent uses them.
+
+Prerequisites:
+- A Microsoft Foundry project with a toolbox that exposes
+  ``skill://index.json`` with ``skill-md`` entries
+- FOUNDRY_PROJECT_ENDPOINT and FOUNDRY_MODEL environment variables set
+- FOUNDRY_TOOLBOX_MCP_SERVER_URL: the toolbox's MCP endpoint URL, e.g.
+  ``https://<account>.services.ai.azure.com/api/projects/<project>/toolboxes/<name>/mcp?api-version=v1``
+- Azure CLI authentication (``az login``)
+"""
+
+
+class _BearerAuth(httpx.Auth):
+    """Attach a fresh Foundry bearer token to every request."""
+
+    def __init__(self, credential: TokenCredential) -> None:
+        self._get_token = get_bearer_token_provider(credential, "https://ai.azure.com/.default")
+
+    def auth_flow(self, request: httpx.Request) -> Generator[httpx.Request, httpx.Response, None]:
+        request.headers["Authorization"] = f"Bearer {self._get_token()}"
+        yield request
+
+
+async def main() -> None:
+    """Example showing toolbox-hosted MCP skills for a Foundry Chat Client agent."""
+    credential = AzureCliCredential()
+
+    # HTTP client that signs every request with a fresh Foundry bearer token
+    # and advertises the toolbox preview feature flag, plus the MCP streamable
+    # HTTP transport that uses it.
+    async with (
+        httpx.AsyncClient(
+            auth=_BearerAuth(credential),
+            headers={"Foundry-Features": "Toolboxes=V1Preview"},
+            timeout=httpx.Timeout(30.0, read=300.0),
+            follow_redirects=True,
+        ) as http_client,
+        streamable_http_client(
+            url=os.environ["FOUNDRY_TOOLBOX_MCP_SERVER_URL"],
+            http_client=http_client,
+        ) as (read, write, _),
+        ClientSession(read, write) as session,
+    ):
+        await session.initialize()
+
+        # Discover skills served by the toolbox and inject them as a context provider.
+        skills_provider = SkillsProvider(MCPSkillsSource(client=session))
+
+        async with Agent(
+            client=FoundryChatClient(credential=credential),
+            name="ToolboxMCPSkillsAgent",
+            instructions="You are a helpful assistant. Use available skills to answer the user.",
+            context_providers=[skills_provider],
+        ) as agent:
+            query = input("User: ").strip()  # noqa: ASYNC250
+            if not query:
+                return
+            response = await agent.run(query)
+            print(f"Assistant: {response.text}")
+
+
+if __name__ == "__main__":
+    asyncio.run(main())