refactor: McpError renamed and flatten parameters

Author: Kludex

src/mcp/client/session_group.py

@@ -382,7 +382,10 @@ async def _aggregate_components(self, server_info: types.Implementation, session
         # Check for duplicates.
         matching_prompts = prompts_temp.keys() & self._prompts.keys()
         if matching_prompts:
-            raise MCPError(code=types.INVALID_PARAMS, message=f"{matching_prompts} already exist in group prompts.")
+            raise MCPError(  # pragma: no cover
+                code=types.INVALID_PARAMS,
+                message=f"{matching_prompts} already exist in group prompts.",
+            )
         matching_resources = resources_temp.keys() & self._resources.keys()
         if matching_resources:
             raise MCPError(  # pragma: no cover

src/mcp/shared/exceptions.py

@@ -24,7 +24,7 @@ def message(self) -> str:
 
     @property
     def data(self) -> Any:
-        return self.error.data
+        return self.error.data  # pragma: no cover
 
     @classmethod
     def from_jsonrpc_error(cls, error: JSONRPCError) -> MCPError: