Add ServerSessionT type var to Context (#271)

* Add ServerSessionT type var to Context

* Passing locally

* Try now

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

@@ -1,3 +1,5 @@
+from __future__ import annotations as _annotations
+
 import inspect
 from typing import TYPE_CHECKING, Any, Callable
 
@@ -9,6 +11,8 @@ from mcp.server.fastmcp.utilities.func_metadata import FuncMetadata, func_metada
 
 if TYPE_CHECKING:
     from mcp.server.fastmcp.server import Context
+    from mcp.server.session import ServerSessionT
+    from mcp.shared.context import LifespanContextT
 
 
 class Tool(BaseModel):
@@ -68,7 +72,11 @@ class Tool(BaseModel):
             context_kwarg=context_kwarg,
         )
 
-    async def run(self, arguments: dict, context: "Context | None" = None) -> Any:
+    async def run(
+        self,
+        arguments: dict[str, Any],
+        context: Context[ServerSessionT, LifespanContextT] | None = None,
+    ) -> Any:
         """Run the tool with arguments."""
         try:
             return await self.fn_metadata.call_fn_with_arg_validation(

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

@@ -1,12 +1,16 @@
+from __future__ import annotations as _annotations
+
 from collections.abc import Callable
 from typing import TYPE_CHECKING, Any
 
 from mcp.server.fastmcp.exceptions import ToolError
 from mcp.server.fastmcp.tools.base import Tool
 from mcp.server.fastmcp.utilities.logging import get_logger
+from mcp.shared.context import LifespanContextT
 
 if TYPE_CHECKING:
     from mcp.server.fastmcp.server import Context
+    from mcp.server.session import ServerSessionT
 
 logger = get_logger(__name__)
 
@@ -43,7 +47,10 @@ class ToolManager:
         return tool
 
     async def call_tool(
-        self, name: str, arguments: dict, context: "Context | None" = None
+        self,
+        name: str,
+        arguments: dict[str, Any],
+        context: Context[ServerSessionT, LifespanContextT] | None = None,
     ) -> Any:
         """Call a tool by name with arguments."""
         tool = self.get_tool(name)