fix: Properly parse tool call results from latest schema for MCP Python SDK

Author: clareliguori

e2e_tests/python/server_clients/server.py

@@ -95,9 +95,31 @@ async def execute_tool(
                 result = await self.session.call_tool(tool_name, arguments)
                 logging.info(f"Finished executing {tool_name}")
 
+                if hasattr(result, "isError") and result.isError:
+                    raise Exception(f"Error executing tool: {result}")
+
+                if hasattr(result, "structuredContent") and result.structuredContent:
+                    return {
+                        "toolUseId": tool_use_id,
+                        "content": [{"text": str(result.structuredContent)}],
+                        "status": "success",
+                    }
+
+                content = []
+                if hasattr(result, "content"):
+                    for block in result.content:
+                        if hasattr(block, "type") and block.type == "text":
+                            content.append({"text": block.text})
+                        else:
+                            raise Exception(
+                                f"Unexpected content type: {getattr(block, 'type', 'unknown')}"
+                            )
+                else:
+                    raise Exception(f"No content found in result: {str(result)}")
+
                 return {
                     "toolUseId": tool_use_id,
-                    "content": [{"text": str(result)}],
+                    "content": content,
                     "status": "success",
                 }
 

e2e_tests/python/server_clients/servers.py

@@ -56,13 +56,6 @@ async def execute_tool(
                 arguments=arguments,
             )
 
-            if isinstance(result, dict) and "progress" in result:
-                progress = result["progress"]
-                total = result["total"]
-                percentage = (progress / total) * 100
-                logging.info(f"Progress: {progress}/{total} " f"({percentage:.1f}%)")
-                raise "Does not support progress notifications from tools yet"
-
             return {"toolResult": result}
         except ValueError:
             return {

examples/chatbots/python/server_clients/server.py

@@ -95,18 +95,31 @@ async def execute_tool(
                 result = await self.session.call_tool(tool_name, arguments)
                 logging.info(f"Finished executing {tool_name}")
 
-                if isinstance(result, dict) and "progress" in result:
-                    progress = result["progress"]
-                    total = result["total"]
-                    percentage = (progress / total) * 100
-                    logging.info(
-                        f"Progress: {progress}/{total} " f"({percentage:.1f}%)"
-                    )
-                    raise "Does not support progress notifications from tools yet"
+                if hasattr(result, "isError") and result.isError:
+                    raise Exception(f"Error executing tool: {result}")
+
+                if hasattr(result, "structuredContent") and result.structuredContent:
+                    return {
+                        "toolUseId": tool_use_id,
+                        "content": [{"text": str(result.structuredContent)}],
+                        "status": "success",
+                    }
+
+                content = []
+                if hasattr(result, "content"):
+                    for block in result.content:
+                        if hasattr(block, "type") and block.type == "text":
+                            content.append({"text": block.text})
+                        else:
+                            raise Exception(
+                                f"Unexpected content type: {getattr(block, 'type', 'unknown')}"
+                            )
+                else:
+                    raise Exception(f"No content found in result: {str(result)}")
 
                 return {
                     "toolUseId": tool_use_id,
-                    "content": [{"text": str(result)}],
+                    "content": content,
                     "status": "success",
                 }