execute_blender_code
Run Python code directly in Blender to automate 3D modeling tasks, control materials, manipulate objects, and create scenes through step-by-step execution.
Instructions
Execute arbitrary Python code in Blender. Make sure to do it step-by-step by breaking it into smaller chunks.
Parameters:
code: The Python code to execute
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes |
Implementation Reference
- src/blender_mcp/server.py:271-288 (handler)The primary handler function implementing the 'execute_blender_code' tool. It sends the provided Python code to the Blender connection for execution and handles errors.
@mcp.tool() def execute_blender_code(ctx: Context, code: str) -> str: """ Execute arbitrary Python code in Blender. Make sure to do it step-by-step by breaking it into smaller chunks. Parameters: - code: The Python code to execute """ try: # Get the global connection blender = get_blender_connection() result = blender.send_command("execute_code", {"code": code}) return f"Code executed successfully: {result.get('result', '')}" except Exception as e: logger.error(f"Error executing code: {str(e)}") return f"Error executing code: {str(e)}" - src/blender_mcp/server.py:273-278 (schema)The docstring within the handler provides the tool schema, describing the purpose, parameters (code: str), and usage notes.
""" Execute arbitrary Python code in Blender. Make sure to do it step-by-step by breaking it into smaller chunks. Parameters: - code: The Python code to execute """ - src/blender_mcp/server.py:271-271 (registration)The @mcp.tool() decorator registers the function as an MCP tool named 'execute_blender_code' based on its name.
@mcp.tool() - src/blender_mcp/server.py:205-235 (helper)Supporting helper function that manages the persistent connection to Blender, called within the handler to obtain the connection instance.
def get_blender_connection(): """Get or create a persistent Blender connection""" global _blender_connection, _polyhaven_enabled # Add _polyhaven_enabled to globals # If we have an existing connection, check if it's still valid if _blender_connection is not None: try: # First check if PolyHaven is enabled by sending a ping command result = _blender_connection.send_command("get_polyhaven_status") # Store the PolyHaven status globally _polyhaven_enabled = result.get("enabled", False) return _blender_connection except Exception as e: # Connection is dead, close it and create a new one logger.warning(f"Existing connection is no longer valid: {str(e)}") try: _blender_connection.disconnect() except: pass _blender_connection = None # Create a new connection if needed if _blender_connection is None: _blender_connection = BlenderConnection(host="localhost", port=9876) if not _blender_connection.connect(): logger.error("Failed to connect to Blender") _blender_connection = None raise Exception("Could not connect to Blender. Make sure the Blender addon is running.") logger.info("Created new persistent connection to Blender") return _blender_connection