BlenderMCP

Instructions

Implementation Reference

• src/blender_mcp/server.py:257-273 (handler)

  The handler function for the 'get_object_info' MCP tool. It is registered via the @mcp.tool() decorator and forwards the request to the Blender addon via socket, returning the JSON-formatted response.
  @mcp.tool() def get_object_info(ctx: Context, object_name: str) -> str: """ Get detailed information about a specific object in the Blender scene. Parameters: - object_name: The name of the object to get information about """ try: blender = get_blender_connection() result = blender.send_command("get_object_info", {"name": object_name}) # Just return the JSON representation of what Blender sent us return json.dumps(result, indent=2) except Exception as e: logger.error(f"Error getting object info from Blender: {str(e)}") return f"Error getting object info: {str(e)}"
• src/blender_mcp/server.py:257-257 (registration)

  The @mcp.tool() decorator registers the get_object_info function as an MCP tool.
  @mcp.tool()
• src/blender_mcp/server.py:259-264 (schema)

  Docstring providing the tool description and input parameter schema.
  """ Get detailed information about a specific object in the Blender scene. Parameters: - object_name: The name of the object to get information about """
• src/blender_mcp/server.py:112-166 (helper)

  The send_command method in BlenderConnection class, which is called by the handler to communicate with the Blender addon socket server.
  def send_command(self, command_type: str, params: Dict[str, Any] = None) -> Dict[str, Any]: """Send a command to Blender and return the response""" if not self.sock and not self.connect(): raise ConnectionError("Not connected to Blender") command = { "type": command_type, "params": params or {} } try: # Log the command being sent logger.info(f"Sending command: {command_type} with params: {params}") # Send the command self.sock.sendall(json.dumps(command).encode('utf-8')) logger.info(f"Command sent, waiting for response...") # Set a timeout for receiving - use the same timeout as in receive_full_response self.sock.settimeout(15.0) # Match the addon's timeout # Receive the response using the improved receive_full_response method response_data = self.receive_full_response(self.sock) logger.info(f"Received {len(response_data)} bytes of data") response = json.loads(response_data.decode('utf-8')) logger.info(f"Response parsed, status: {response.get('status', 'unknown')}") if response.get("status") == "error": logger.error(f"Blender error: {response.get('message')}") raise Exception(response.get("message", "Unknown error from Blender")) return response.get("result", {}) except socket.timeout: logger.error("Socket timeout while waiting for response from Blender") # Don't try to reconnect here - let the get_blender_connection handle reconnection # Just invalidate the current socket so it will be recreated next time self.sock = None raise Exception("Timeout waiting for Blender response - try simplifying your request") except (ConnectionError, BrokenPipeError, ConnectionResetError) as e: logger.error(f"Socket connection error: {str(e)}") self.sock = None raise Exception(f"Connection to Blender lost: {str(e)}") except json.JSONDecodeError as e: logger.error(f"Invalid JSON response from Blender: {str(e)}") # Try to log what was received if 'response_data' in locals() and response_data: logger.error(f"Raw response (first 200 bytes): {response_data[:200]}") raise Exception(f"Invalid response from Blender: {str(e)}") except Exception as e: logger.error(f"Error communicating with Blender: {str(e)}") # Don't try to reconnect here - let the get_blender_connection handle reconnection self.sock = None raise Exception(f"Communication error with Blender: {str(e)}")