chore(mcp): remove dead parse_request decorator and utility code

superset/mcp_service/CLAUDE.md

@@ -444,8 +444,6 @@ MCP_USER_RESOLVER = None         # Custom function to extract username from JWT
 # RBAC
 MCP_RBAC_ENABLED = True          # Enable permission checking (default: True)
 
-# Request Parsing
-MCP_PARSE_REQUEST_ENABLED = True # Accept JSON string requests (workaround for client bugs)
 
 # Response Caching (optional, uses in-memory store by default; Redis when MCP_STORE_CONFIG enabled)
 MCP_CACHE_CONFIG = {

superset/mcp_service/app.py

@@ -263,8 +263,7 @@ def get_default_instructions(branding: str = "Apache Superset") -> str:
 
 Input format:
 - Tool request parameters accept structured objects (dicts/JSON)
-- When MCP_PARSE_REQUEST_ENABLED is True (default), string-serialized JSON is also
-  accepted as input, which works around double-serialization bugs in some MCP clients
+- FastMCP 3.1+ handles Pydantic BaseModel parameters natively
 
 Feature Availability:
 - Call get_instance_info to discover accessible menus for the current user.

superset/mcp_service/auth.py

@@ -569,8 +569,7 @@ def _get_app_context_manager() -> AbstractContextManager[None]:
     is_async = inspect.iscoroutinefunction(tool_func)
 
     # Detect if the original function expects a ctx: Context parameter.
-    # If so, we inject it via get_context() at call time so tool functions
-    # don't need @parse_request to handle Context injection.
+    # If so, we inject it via get_context() at call time.
     from fastmcp import Context as FMContext
 
     _tool_sig = inspect.signature(tool_func)
@@ -696,33 +695,23 @@ def sync_wrapper(*args: Any, **kwargs: Any) -> Any:
     # Copy docstring from original function (not wrapper, which may have lost it)
     new_wrapper.__doc__ = tool_func.__doc__
 
-    # Set __signature__ from the original function, but:
-    # 1. Remove ctx parameter - FastMCP tools don't expose it to clients
-    # 2. Skip if original has *args (parse_request output has its own handling)
-    has_var_positional = any(
-        p.kind == inspect.Parameter.VAR_POSITIONAL
-        for p in _tool_sig.parameters.values()
+    # Set __signature__ from the original function, removing ctx parameter
+    # since FastMCP tools don't expose it to clients.
+    new_params = []
+    for _name, param in _tool_sig.parameters.items():
+        # Skip ctx parameter - FastMCP tools don't expose it to clients
+        if param.annotation is FMContext or (
+            hasattr(param.annotation, "__name__")
+            and param.annotation.__name__ == "Context"
+        ):
+            continue
+        new_params.append(param)
+    new_wrapper.__signature__ = _tool_sig.replace(  # type: ignore[attr-defined]
+        parameters=new_params
     )
 
-    if not has_var_positional:
-        # For functions without *args, preserve signature but remove ctx
-        new_params = []
-        for _name, param in _tool_sig.parameters.items():
-            # Skip ctx parameter - FastMCP tools don't expose it to clients
-            if param.annotation is FMContext or (
-                hasattr(param.annotation, "__name__")
-                and param.annotation.__name__ == "Context"
-            ):
-                continue
-            new_params.append(param)
-        new_wrapper.__signature__ = _tool_sig.replace(  # type: ignore[attr-defined]
-            parameters=new_params
-        )
-
-        # Also remove ctx from annotations to match signature
-        if "ctx" in new_wrapper.__annotations__:
-            del new_wrapper.__annotations__["ctx"]
-    # For functions with *args (parse_request output), the signature
-    # is already set by parse_request without ctx.
+    # Also remove ctx from annotations to match signature
+    if "ctx" in new_wrapper.__annotations__:
+        del new_wrapper.__annotations__["ctx"]
 
     return new_wrapper  # type: ignore[return-value]

superset/mcp_service/mcp_config.py

@@ -59,12 +59,6 @@
 # per RFC 6750 Section 3.1. This flag NEVER affects client-facing output.
 MCP_JWT_DEBUG_ERRORS = False
 
-# Enable parse_request decorator for MCP tools.
-# When True (default), tool requests are automatically parsed from JSON strings
-# to Pydantic models, working around a Claude Code double-serialization bug
-# (https://github.com/anthropics/claude-code/issues/5504).
-# Set to False to disable and let FastMCP handle request parsing natively.
-MCP_PARSE_REQUEST_ENABLED = True
 
 # Session configuration for local development
 MCP_SESSION_CONFIG = {