FreeCAD MCP Integration for AI-Assisted CAD Design

Overview

The FreeCAD MCP (Model Control Protocol) provides a simplified interface for interacting with FreeCAD through a server-client architecture. This allows users to execute commands and retrieve information about the current FreeCAD document and scene.

Features

1. get_scene_info

• Description: Retrieves comprehensive information about the current FreeCAD document, including:
• Document properties (name, label, filename, object count)
• Detailed object information (type, position, rotation, shape properties)
• Sketch data (geometry, constraints)
• View information (camera position, direction, etc.)

2. run_script

• Description: Executes arbitrary Python code within the FreeCAD context. This allows users to perform complex operations, create new objects, modify existing ones, and automate tasks using FreeCAD's Python API.

Configuration

To configure the MCP server, you can use a JSON format to specify the server settings. Below is an example configuration:

{
    "mcpServers": {
        "freecad": {
            "command": "C:\\ProgramData\\anaconda3\\python.exe",
            "args": [\
                "C:\\Users\\USER\\AppData\\Roaming\\FreeCAD\\Mod\\freecad_mcp\\src\\freecad_bridge.py"\
            ]
        }
    }
}

Configuration Details

• command: The path to the Python executable that will run the FreeCAD MCP server. This can vary based on your operating system:
• Windows: Typically, it might look like C:\\ProgramData\\anaconda3\\python.exe or C:\\Python39\\python.exe.
• Linux: It could be /usr/bin/python3 or the path to your Python installation.
• macOS: Usually, it would be /usr/local/bin/python3 or the path to your Python installation.
• args: An array of arguments to pass to the Python command. The first argument should be the path to the freecad_bridge.py script, which is responsible for handling the MCP server logic. Make sure to adjust the path according to your installation.

Example for Different Operating Systems

Windows

{
    "mcpServers": {
        "freecad": {
            "command": "C:\\ProgramData\\anaconda3\\python.exe",
            "args": [\
                "C:\\Users\\USER\\AppData\\Roaming\\FreeCAD\\Mod\\freecad_mcp\\src\\freecad_bridge.py"\
            ]
        }
    }
}

Linux

{
    "mcpServers": {
        "freecad": {
            "command": "/usr/bin/python3",
            "args": [\
                "/home/USER/.FreeCAD/Mod/freecad_mcp/src/freecad_bridge.py"\
            ]
        }
    }
}

macOS

{
    "mcpServers": {
        "freecad": {
            "command": "/usr/local/bin/python3",
            "args": [\
                "/Users/USER/Library/Preferences/FreeCAD/Mod/freecad_mcp/src/freecad_bridge.py"\
            ]
        }
    }
}

Usage

To use the FreeCAD MCP, you can connect to the server and send commands as follows:

import socket
import json

# Connect to the FreeCAD MCP server
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(('localhost', 9876))

# Example: Get scene information
command = {
    "type": "get_scene_info"
}
client.sendall(json.dumps(command).encode('utf-8'))

# Receive the response
response = client.recv(4096)
print(json.loads(response.decode('utf-8')))

# Example: Run a script
script = """
import FreeCAD
doc = FreeCAD.ActiveDocument
box = doc.addObject("Part::Box", "MyBox")
box.Length = 20
box.Width = 20
box.Height = 20
doc.recompute()
"""
command = {
    "type": "run_script",
    "params": {
        "script": script
    }
}
client.sendall(json.dumps(command).encode('utf-8'))

# Receive the response
response = client.recv(4096)
print(json.loads(response.decode('utf-8')))

# Close the connection
client.close()

Installation

1. Clone the repository or download the files.
2. Place the freecad_mcp directory in your FreeCAD modules directory:
3. Windows: %APPDATA%/FreeCAD/Mod/
4. Linux: ~/.FreeCAD/Mod/
5. macOS: ~/Library/Preferences/FreeCAD/Mod/
6. Restart FreeCAD and select the "FreeCAD MCP" workbench from the workbench selector.

Contributing

Feel free to contribute by submitting issues or pull requests. Your feedback and contributions are welcome!

License

This project is licensed under the MIT License. See the LICENSE file for details.