FreeCAD MCP

This repository is a FreeCAD MCP that allows you to control FreeCAD from Claude Desktop.

It now ships with both a classic stdio transport and a FastAPI-powered Server-Sent Events (SSE) service. Choose the option that best matches how your MCP client prefers to connect.

MCP server commands

Once installed with uvx, the project provides two executables:

Command	Transport	Purpose
freecad-mcp	stdio	Launches the original MCP server that Claude Desktop starts as a subprocess.
freecad-mcp-sse	Server-Sent Events (FastAPI + uvicorn)	Hosts the same tools over HTTP with configurable host/port/SSE paths.

The SSE server accepts the same --only-text-feedback flag as the stdio version and adds options for --host, --port, --sse-path, and --message-path so it can be embedded into existing FastAPI deployments or reverse proxies.

Demo

Design a flange

Design a toy car

Design a part from 2D drawing

Input 2D drawing

Demo

This is the conversation history. https://claude.ai/share/7b48fd60-68ba-46fb-bb21-2fbb17399b48

Install addon

FreeCAD Addon directory is

• Windows: %APPDATA%\FreeCAD\Mod\
• Mac: ~/Library/Application\ Support/FreeCAD/Mod/
• Linux:
  • Ubuntu: ~/.FreeCAD/Mod/ or ~/snap/freecad/common/Mod/ (if you install FreeCAD from snap)
  • Debian: ~/.local/share/FreeCAD/Mod

Please put addon/FreeCADMCP directory to the addon directory.

git clone https://github.com/neka-nat/freecad-mcp.git
cd freecad-mcp
cp -r addon/FreeCADMCP ~/.FreeCAD/Mod/

When you install addon, you need to restart FreeCAD. You can select "MCP Addon" from Workbench list and use it.

And you can start RPC server by "Start RPC Server" command in "FreeCAD MCP" toolbar.

Setting up Claude Desktop

Pre-installation of the uvx is required. Edit the Claude Desktop config file, claude_desktop_config.json, and choose the transport that fits your workflow.

stdio transport (default)

Use this option when Claude Desktop should launch the MCP server as a subprocess.

User configuration

{
  "mcpServers": {
    "freecad": {
      "command": "uvx",
      "args": ["freecad-mcp"]
    }
  }
}

To save tokens, append the --only-text-feedback flag so only text responses are returned:

{
  "mcpServers": {
    "freecad": {
      "command": "uvx",
      "args": ["freecad-mcp", "--only-text-feedback"]
    }
  }
}

Developer configuration

Clone this repository and point Claude Desktop at the local checkout so you can edit the code without reinstalling the package:

git clone https://github.com/neka-nat/freecad-mcp.git

{
  "mcpServers": {
    "freecad": {
      "command": "uv",
      "args": ["--directory", "/path/to/freecad-mcp/", "run", "freecad-mcp"]
    }
  }
}

SSE transport (FastAPI + uvicorn)

Run the SSE server when you need to expose FreeCAD MCP over HTTP, share it between multiple clients, or take advantage of streaming responses provided by FastMCP.

Start the server in a terminal:

uvx freecad-mcp-sse --host 127.0.0.1 --port 8099

Adjust --host, --port, --sse-path, --message-path, or --only-text-feedback to match your environment. Pass --help to list every option.

Then register the SSE endpoint with Claude Desktop (requires Claude Desktop 0.6.1 or later):

{
  "mcpServers": {
    "freecad-sse": {
      "type": "sse",
      "url": "http://127.0.0.1:8099/sse"
    }
  }
}

Claude discovers the message endpoint from the SSE handshake automatically. If you change --sse-path or --message-path, update the URL above to match the new SSE path.

Tools

• create_document: Create a new document in FreeCAD.
• create_object: Create a new object in FreeCAD.
• edit_object: Edit an object in FreeCAD.
• delete_object: Delete an object in FreeCAD.
• execute_code: Execute arbitrary Python code in FreeCAD.
• insert_part_from_library: Insert a part from the parts library.
• get_view: Get a screenshot of the active view.
• get_objects: Get all objects in a document.
• get_object: Get an object in a document.
• get_parts_list: Get the list of parts in the parts library.

Contributors

Made with contrib.rocks.