Merge branch 'main' into jonvet/resources-with-context

Author: jonvet

.pre-commit-config.yaml

@@ -7,15 +7,29 @@ repos:
       - id: prettier
         types_or: [yaml, json5]
 
-  - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.8.1
+  - repo: local
     hooks:
       - id: ruff-format
+        name: Ruff Format
+        entry: uv run ruff
+        args: [format]
+        language: system
+        types: [python]
+        pass_filenames: false
       - id: ruff
-        args: [--fix, --exit-non-zero-on-fix]
-
-  - repo: local
-    hooks:
+        name: Ruff
+        entry: uv run ruff
+        args: ["check", "--fix", "--exit-non-zero-on-fix"]
+        types: [python]
+        language: system
+        pass_filenames: false
+      - id: pyright
+        name: pyright
+        entry: uv run pyright
+        args: [src]
+        language: system
+        types: [python]
+        pass_filenames: false
       - id: uv-lock-check
         name: Check uv.lock is up to date
         entry: uv lock --check

README.md

@@ -194,7 +194,7 @@ mcp = FastMCP("My App", lifespan=app_lifespan)
 @mcp.tool()
 def query_db(ctx: Context) -> str:
     """Tool that uses initialized resources"""
-    db = ctx.request_context.lifespan_context["db"]
+    db = ctx.request_context.lifespan_context.db
     return db.query()
 ```
 

src/mcp/server/fastmcp/tools/base.py

@@ -2,7 +2,7 @@
 
 import inspect
 from collections.abc import Callable
-from typing import TYPE_CHECKING, Any
+from typing import TYPE_CHECKING, Any, get_origin
 
 from pydantic import BaseModel, Field
 
@@ -53,7 +53,9 @@ def from_function(
         if context_kwarg is None:
             sig = inspect.signature(fn)
             for param_name, param in sig.parameters.items():
-                if param.annotation is Context:
+                if get_origin(param.annotation) is not None:
+                    continue
+                if issubclass(param.annotation, Context):
                     context_kwarg = param_name
                     break
 

tests/server/fastmcp/test_tool_manager.py

@@ -4,8 +4,11 @@
 import pytest
 from pydantic import BaseModel
 
+from mcp.server.fastmcp import Context, FastMCP
 from mcp.server.fastmcp.exceptions import ToolError
 from mcp.server.fastmcp.tools import ToolManager
+from mcp.server.session import ServerSessionT
+from mcp.shared.context import LifespanContextT
 
 
 class TestAddTools:
@@ -194,8 +197,6 @@ def concat_strs(vals: list[str] | str) -> str:
 
     @pytest.mark.anyio
     async def test_call_tool_with_complex_model(self):
-        from mcp.server.fastmcp import Context
-
         class MyShrimpTank(BaseModel):
             class Shrimp(BaseModel):
                 name: str
@@ -223,8 +224,6 @@ def name_shrimp(tank: MyShrimpTank, ctx: Context) -> list[str]:
 class TestToolSchema:
     @pytest.mark.anyio
     async def test_context_arg_excluded_from_schema(self):
-        from mcp.server.fastmcp import Context
-
         def something(a: int, ctx: Context) -> int:
             return a
 
@@ -241,7 +240,6 @@ class TestContextHandling:
     def test_context_parameter_detection(self):
         """Test that context parameters are properly detected in
         Tool.from_function()."""
-        from mcp.server.fastmcp import Context
 
         def tool_with_context(x: int, ctx: Context) -> str:
             return str(x)
@@ -256,10 +254,17 @@ def tool_without_context(x: int) -> str:
         tool = manager.add_tool(tool_without_context)
         assert tool.context_kwarg is None
 
+        def tool_with_parametrized_context(
+            x: int, ctx: Context[ServerSessionT, LifespanContextT]
+        ) -> str:
+            return str(x)
+
+        tool = manager.add_tool(tool_with_parametrized_context)
+        assert tool.context_kwarg == "ctx"
+
     @pytest.mark.anyio
     async def test_context_injection(self):
         """Test that context is properly injected during tool execution."""
-        from mcp.server.fastmcp import Context, FastMCP
 
         def tool_with_context(x: int, ctx: Context) -> str:
             assert isinstance(ctx, Context)
@@ -276,7 +281,6 @@ def tool_with_context(x: int, ctx: Context) -> str:
     @pytest.mark.anyio
     async def test_context_injection_async(self):
         """Test that context is properly injected in async tools."""
-        from mcp.server.fastmcp import Context, FastMCP
 
         async def async_tool(x: int, ctx: Context) -> str:
             assert isinstance(ctx, Context)
@@ -293,7 +297,6 @@ async def async_tool(x: int, ctx: Context) -> str:
     @pytest.mark.anyio
     async def test_context_optional(self):
         """Test that context is optional when calling tools."""
-        from mcp.server.fastmcp import Context
 
         def tool_with_context(x: int, ctx: Context | None = None) -> str:
             return str(x)
@@ -307,7 +310,6 @@ def tool_with_context(x: int, ctx: Context | None = None) -> str:
     @pytest.mark.anyio
     async def test_context_error_handling(self):
         """Test error handling when context injection fails."""
-        from mcp.server.fastmcp import Context, FastMCP
 
         def tool_with_context(x: int, ctx: Context) -> str:
             raise ValueError("Test error")