Typing fixes

Strict pyright mode results in a lot of issues regarding non fully
determined types, due to Generics. These are some issues I came across
today. We are still far from being clean on pyright.

Author: dsp-ant

mcp_python/server/__init__.py

@@ -20,6 +20,8 @@
     CompleteRequest,
     ErrorData,
     JSONRPCMessage,
+    ListPromptsRequest,
+    ListPromptsResult,
     ListResourcesRequest,
     ListResourcesResult,
     LoggingLevel,
@@ -57,8 +59,6 @@ def request_context(self) -> RequestContext:
         return request_ctx.get()
 
     def list_prompts(self):
-        from mcp_python.types import ListPromptsRequest, ListPromptsResult
-
         def decorator(func: Callable[[], Awaitable[list[Prompt]]]):
             logger.debug(f"Registering handler for PromptListRequest")
 
@@ -90,7 +90,7 @@ def decorator(
 
             async def handler(req: GetPromptRequest):
                 prompt_get = await func(req.params.name, req.params.arguments)
-                messages = []
+                messages: list[SamplingMessage] = []
                 for message in prompt_get.messages:
                     match message.content:
                         case str() as text_content:

mcp_python/server/stdio.py

@@ -7,10 +7,9 @@
 
 from mcp_python.types import JSONRPCMessage
 
-
 @asynccontextmanager
 async def stdio_server(
-    stdin: anyio.AsyncFile | None = None, stdout: anyio.AsyncFile | None = None
+    stdin: anyio.AsyncFile[str] | None = None, stdout: anyio.AsyncFile[str] | None = None
 ):
     """
     Server transport for stdio: this communicates with an MCP client by reading from the current process' stdin and writing to stdout.