Add MCP Client Plugin (#123)

Adds support for MCP clients in an MCP plugin. Makes use of the AI
plugin system introduced in #121 .

- Added new MCP package (packages/mcp/) with AI plugin and transport
functionality
  - Updated chat prompt handling for MCP integration
- Changed token from being parsed into JWT tokens because that's not
necessarily true for many types of tokens. Github for eg, doesn't use
JWT.

This is roughly how the system works:
```mermaid
sequenceDiagram
      participant U as User
      participant CP as ChatPrompt
      participant P as MCP Plugin
      participant MCP as MCP Server
      participant M as AI Model

      U->>CP: send(input)

      CP->>P: on_build_functions(functions)
      P->>MCP: get_available_tools()
      MCP-->>P: tool_definitions
      P-->>CP: functions + mcp_tools

      CP->>M: generate_text(input, system, functions)

      alt Model calls MCP tool
          M-->>CP: function_call(mcp_tool, params)
          CP-->>M: function_result
      end

      M-->>CP: response
      CP-->>U: ChatSendResult
```






















#### PR Dependency Tree


* **PR #123** 👈
  * **PR #126**

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

Author: heyitsaamir

.gitignore

@@ -32,3 +32,8 @@ CLAUDE.md
 
 .env.claude/
 .claude/
+
+tests/**/.vscode/
+tests/**/appPackage/
+tests/**/infra/
+tests/**/teamsapp*

packages/ai/src/microsoft/teams/ai/agent.py

@@ -5,6 +5,8 @@
 
 from typing import Any, Awaitable, Callable
 
+from microsoft.teams.ai.plugin import AIPluginProtocol
+
 from .ai_model import AIModel
 from .chat_prompt import ChatPrompt, ChatSendResult
 from .function import Function
@@ -18,8 +20,15 @@ class Agent(ChatPrompt):
     through the existence of the Agent.
     """
 
-    def __init__(self, model: AIModel, *, memory: Memory | None = None, functions: list[Function[Any]] | None = None):
-        super().__init__(model, functions=functions)
+    def __init__(
+        self,
+        model: AIModel,
+        *,
+        memory: Memory | None = None,
+        functions: list[Function[Any]] | None = None,
+        plugins: list[AIPluginProtocol] | None = None,
+    ):
+        super().__init__(model, functions=functions, plugins=plugins)
         self.memory = memory or ListMemory()
 
     async def send(

packages/ai/src/microsoft/teams/ai/chat_prompt.py

@@ -6,7 +6,7 @@
 import inspect
 from dataclasses import dataclass
 from inspect import isawaitable
-from typing import Any, Awaitable, Callable, TypeVar
+from typing import Any, Awaitable, Callable, Self, TypeVar
 
 from pydantic import BaseModel
 
@@ -36,11 +36,11 @@ def __init__(
         self.functions: dict[str, Function[Any]] = {func.name: func for func in functions} if functions else {}
         self.plugins: list[AIPluginProtocol] = plugins or []
 
-    def with_function(self, function: Function[T]) -> "ChatPrompt":
+    def with_function(self, function: Function[T]) -> Self:
         self.functions[function.name] = function
         return self
 
-    def with_plugin(self, plugin: AIPluginProtocol) -> "ChatPrompt":
+    def with_plugin(self, plugin: AIPluginProtocol) -> Self:
         """Add a plugin to the chat prompt."""
         self.plugins.append(plugin)
         return self
@@ -122,25 +122,21 @@ async def _run_build_system_message_hooks(self, system_message: SystemMessage |
         return current_system_message
 
     async def _build_wrapped_functions(self) -> dict[str, Function[BaseModel]] | None:
-        wrapped_functions: dict[str, Function[BaseModel]] | None = None
-        if self.functions:
-            wrapped_functions = {}
-            for name, func in self.functions.items():
-                wrapped_functions[name] = Function[BaseModel](
-                    name=func.name,
-                    description=func.description,
-                    parameter_schema=func.parameter_schema,
-                    handler=self._wrap_function_handler(func.handler, name),
-                )
-
-        if wrapped_functions:
-            functions_list = list(wrapped_functions.values())
-            for plugin in self.plugins:
-                plugin_result = await plugin.on_build_functions(functions_list)
-                if plugin_result is not None:
-                    functions_list = plugin_result
+        functions_list = list(self.functions.values()) if self.functions else []
+        for plugin in self.plugins:
+            plugin_result = await plugin.on_build_functions(functions_list)
+            if plugin_result is not None:
+                functions_list = plugin_result
 
-            wrapped_functions = {func.name: func for func in functions_list}
+        wrapped_functions: dict[str, Function[BaseModel]] | None = None
+        wrapped_functions = {}
+        for func in functions_list:
+            wrapped_functions[func.name] = Function[BaseModel](
+                name=func.name,
+                description=func.description,
+                parameter_schema=func.parameter_schema,
+                handler=self._wrap_function_handler(func.handler, func.name),
+            )
 
         return wrapped_functions
 

packages/ai/src/microsoft/teams/ai/function.py

@@ -4,7 +4,7 @@
 """
 
 from dataclasses import dataclass
-from typing import Any, Awaitable, Generic, Protocol, TypeVar, Union
+from typing import Any, Awaitable, Dict, Generic, Protocol, TypeVar, Union
 
 from pydantic import BaseModel
 
@@ -19,7 +19,7 @@ def __call__(self, params: Params) -> Union[str, Awaitable[str]]: ...
 class Function(Generic[Params]):
     name: str
     description: str
-    parameter_schema: type[Params]
+    parameter_schema: Union[type[Params], Dict[str, Any]]
     handler: FunctionHandler[Params]
 
 

packages/apps/src/microsoft/teams/apps/app_process.py

@@ -13,7 +13,6 @@
     ConversationReference,
     GetUserTokenParams,
     InvokeResponse,
-    JsonWebToken,
     SentActivity,
     TokenProtocol,
     is_invoke_response,
@@ -97,16 +96,16 @@ async def _build_context(
 
         # Check if user is signed in
         is_signed_in = False
-        user_token: Optional[TokenProtocol] = None
+        user_token: Optional[str] = None
         try:
             user_token_res = await api_client.users.token.get(
                 GetUserTokenParams(
-                    connection_name=self.default_connection_name or "default",
+                    connection_name=self.default_connection_name,
                     user_id=activity.from_.id,
                     channel_id=activity.channel_id,
                 )
             )
-            user_token = JsonWebToken(user_token_res.token)
+            user_token = user_token_res.token
             is_signed_in = True
         except Exception:
             # User token not available

packages/apps/src/microsoft/teams/apps/routing/activity_context.py

@@ -19,6 +19,7 @@
     CreateConversationParams,
     GetBotSignInResourceParams,
     GetUserTokenParams,
+    JsonWebToken,
     MessageActivityInput,
     SentActivity,
     SignOutUserParams,
@@ -65,6 +66,7 @@ class SignInOptions:
 
     oauth_card_text: str = "Please Sign In..."
     sign_in_button_text: str = "Sign In"
+    connection_name: Optional[str] = None
     override_sign_in_activity: Optional[
         Callable[
             [
@@ -90,7 +92,7 @@ def __init__(
         logger: Logger,
         storage: Storage[str, Any],
         api: ApiClient,
-        user_token: Optional[TokenProtocol],
+        user_token: Optional[str],
         conversation_ref: ConversationReference,
         is_signed_in: bool,
         connection_name: str,
@@ -135,7 +137,8 @@ def user_graph(self) -> "GraphServiceClient":
 
         if self._user_graph is None:
             try:
-                self._user_graph = _get_graph_client(self.user_token)
+                user_token = JsonWebToken(self.user_token)
+                self._user_graph = _get_graph_client(user_token)
             except Exception as e:
                 self.logger.error(f"Failed to create user graph client: {e}")
                 raise RuntimeError(f"Failed to create user graph client: {e}") from e
@@ -247,13 +250,13 @@ async def sign_in(self, options: Optional[SignInOptions] = None) -> Optional[str
         signin_opts = options or DEFAULT_SIGNIN_OPTIONS
         oauth_card_text = signin_opts.oauth_card_text
         sign_in_button_text = signin_opts.sign_in_button_text
-
+        connection_name = signin_opts.connection_name or self.connection_name
         try:
             # Try to get existing token
             token_params = GetUserTokenParams(
                 channel_id=self.activity.channel_id,
                 user_id=self.activity.from_.id,
-                connection_name=self.connection_name,
+                connection_name=connection_name,
             )
             res = await self.api.users.token.get(token_params)
             return res.token
@@ -263,7 +266,7 @@ async def sign_in(self, options: Optional[SignInOptions] = None) -> Optional[str
 
         # Create token exchange state
         token_exchange_state = TokenExchangeState(
-            connection_name=self.connection_name,
+            connection_name=connection_name,
             conversation=self.conversation_ref,
             relates_to=self.activity.relates_to,
             ms_app_id=self.app_id,
@@ -297,7 +300,7 @@ async def sign_in(self, options: Optional[SignInOptions] = None) -> Optional[str
                 attachment=OAuthCardAttachment(
                     content=OAuthCard(
                         text=oauth_card_text,
-                        connection_name=self.connection_name,
+                        connection_name=connection_name,
                         token_exchange_resource=resource.token_exchange_resource,
                         token_post_resource=resource.token_post_resource,
                         buttons=[

packages/mcp/README.md

@@ -0,0 +1,32 @@
+[project]
+name = "microsoft.teams.mcp"
+version = "0.0.1-alpha.4"
+description = "library for handling mcp with teams ai library"
+authors = [{ name = "Microsoft", email = "[email protected]" }]
+readme = "README.md"
+requires-python = ">=3.12"
+repository = "https://github.com/microsoft/teams.py"
+keywords = ["microsoft", "teams", "ai", "bot", "agents"]
+license = "MIT"
+dependencies = [
+    "mcp>=1.13.1",
+    "microsoft-teams-ai",
+    "microsoft-teams-common",
+]
+
+[tool.microsoft-teams.metadata]
+external = true
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/microsoft"]
+
+[tool.hatch.build.targets.sdist]
+include = ["src"]
+
+[tool.uv.sources]
+microsoft-teams-ai = { workspace = true }
+microsoft-teams-common = { workspace = true }

packages/mcp/pyproject.toml

@@ -0,0 +1,8 @@
+"""
+Copyright (c) Microsoft Corporation. All rights reserved.
+Licensed under the MIT License.
+"""
+
+from .ai_plugin import McpClientPlugin, McpClientPluginParams, McpToolDetails
+
+__all__ = ["McpClientPlugin", "McpClientPluginParams", "McpToolDetails"]