more useful comments

Author: BrandonShar

src/mcp/server/fastmcp/utilities/func_metadata.py

@@ -271,7 +271,7 @@ def func_metadata(
     output_info = FieldInfo.from_annotation(_get_typed_annotation(sig.return_annotation, globalns))
     annotation = output_info.annotation
 
-    # if the typehint is CallToolResult, the user intends to return it directly
+    # if the typehint is CallToolResult, the user intends to return it directly without validation
     if isinstance(annotation, type) and issubclass(annotation, CallToolResult):
         return FuncMetadata(arg_model=arguments_model)
 

src/mcp/server/lowlevel/server.py

@@ -505,7 +505,6 @@ async def handler(req: types.CallToolRequest):
                     unstructured_content: UnstructuredContent
                     maybe_structured_content: StructuredContent | None
                     if isinstance(results, types.CallToolResult):
-                        # tool returned a CallToolResult so we'll skip further validation and return it directly
                         return types.ServerResult(results)
                     elif isinstance(results, tuple) and len(results) == 2:
                         # tool returned both structured and unstructured content