Advanced Tools

Blender MCP

Use a standard stdio Blender MCP server with BLENDER_MCP_COMMAND and BLENDER_MCP_ARGS. For the common Blender MCP server, install uv and its matching Blender addon, enable the addon, and start its connection inside Blender. Set the command to your full uvx path and the argument array to ["blender-mcp"]. The Claude Desktop extension also offers these two optional settings. Printer tools work without Blender configured.

1. Call blender_mcp_status with {"connect": true} to initialize the server and discover its tools and input schemas. A connected MCP server does not by itself prove that the Blender addon is running.
2. Call blender_mcp_call with a discovered tool name and its arguments. The full MCP result, including images and errors, is returned. For example:

{
  "tool_name": "get_scene_info",
  "arguments": {"user_prompt": "Inspect the scene before preparing a print."}
}

For advanced Blender operations, forward execute_blender_code with code and the user's original user_prompt. These calls may edit the active scene. Use the discovered schema rather than assuming a tool exists.

blender_mcp_edit_model

The standard MCP edit helper imports an STL, applies ordered edits, and exports an STL without replacing the input or an existing output. Supported operations are decimate:<ratio> (greater than 0 through 1), remesh:<voxel size> (positive, in STL coordinate units), and boolean_union:<STL path>. Other operations can use blender_mcp_call. Both processes must have access to the same file paths. When BLENDER_MCP_COMMAND selects standard MCP, the advertised tool schema requires an explicit output_path for both preview and execution. Legacy-only bridge configurations keep output_path optional for compatibility.

{
  "stl_path": "/path/to/model.stl",
  "output_path": "/path/to/model-edited.stl",
  "operations": ["decimate:0.5"],
  "user_prompt": "Reduce the triangle count of this model for printing.",
  "execute": false
}

The default preview returns the plan and generated Python without launching Blender. Set execute to true to run it. A successful standard edit returns output_verified: true, output_path, byte count, and triangle count after checking the matching export receipt and a valid finite mesh. The helper preserves existing scene objects and requires Object Mode. Inspect the result before slicing; a valid STL is not a guarantee of printability.

The bridge enforces request deadlines, closes child connections, and never replays interrupted editing requests. After a timeout, inspect Blender before trying the edit again because execution may already have started.

Existing custom executables still work through BLENDER_MCP_BRIDGE_COMMAND. They receive MCP_BLENDER_PAYLOAD with the requested file and operations; their results explicitly report output_verified: false. A missing executable configuration is an error when execution is requested. Per-call legacy bridge_command overrides remain disabled unless MCP_ALLOW_EXECUTABLE_ARG=1.