Grasshopper MCP Bridge

Grasshopper MCP Bridge is a bridging server that connects Grasshopper and Claude Desktop using the Model Context Protocol (MCP) standard.

Features

• Connects Grasshopper and Claude Desktop through the MCP protocol
• Provides intuitive tool functions for creating and connecting Grasshopper components
• Supports high-level intent recognition, automatically creating complex component patterns from simple descriptions
• Includes a component knowledge base that understands parameters and connection rules for common components
• Provides component guidance resources to help Claude Desktop correctly connect components

System Architecture

The system consists of the following parts:

1. Grasshopper MCP Component (GH_MCP.gha): A plugin installed in Grasshopper that provides a TCP server to receive commands
2. Python MCP Bridge Server: A bridge server that connects Claude Desktop and the Grasshopper MCP component
3. Component Knowledge Base: JSON files containing component information, patterns, and intents

Installation Instructions

Prerequisites

• Rhino 7 or higher
• Grasshopper
• Python 3.8 or higher
• Claude Desktop

Installation Steps

1. Install the Grasshopper MCP Component

   Method 1: Download the pre-compiled GH_MCP.gha file (Recommended)

   Download the GH_MCP.gha file directly from the GitHub repository and copy it to the Grasshopper components folder:

   %APPDATA%\Grasshopper\Libraries\
   

   Method 2: Build from source

   If you prefer to build from source, clone the repository and build the C# project using Visual Studio.

2. Install the Python MCP Bridge Server

   Method 1: Install from PyPI (Recommended)

   The simplest method is to install directly from PyPI using pip:

   pip install grasshopper-mcp
   

   Method 2: Install from GitHub

   You can also install the latest version from GitHub:

   pip install git+https://github.com/alfredatnycu/grasshopper-mcp.git
   

   Method 3: Install from Source Code

   If you need to modify the code or develop new features, you can clone the repository and install:

   git clone https://github.com/alfredatnycu/grasshopper-mcp.git
   cd grasshopper-mcp
   pip install -e .
   

   Install a Specific Version

   If you need to install a specific version, you can use:

   pip install grasshopper-mcp==0.1.0
   

   Or install from a specific GitHub tag:

   pip install git+https://github.com/alfredatnycu/grasshopper-mcp.git@v0.1.0
   

Usage

1. Start Rhino and Grasshopper

   Launch Rhino and open Grasshopper.

2. Add the GH_MCP Component to Your Canvas

   Find the GH_MCP component in the Grasshopper component panel and add it to your canvas.

3. Start the Python MCP Bridge Server

   Open a terminal and run:

   python -m grasshopper_mcp.bridge
   

   Note: The command grasshopper-mcp might not work directly due to Python script path issues. Using python -m grasshopper_mcp.bridge is the recommended and more reliable method.

4. Connect Claude Desktop to the MCP Bridge

   Method 1: Manual Connection

   In Claude Desktop, connect to the MCP Bridge server using the following settings:

   • Protocol: MCP
   • Host: localhost
   • Port: 8080

   Method 2: Configure Claude Desktop to Auto-Start the Bridge

   You can configure Claude Desktop to automatically start the MCP Bridge server by modifying its configuration:

   "grasshopper": {
     "command": "python",
     "args": ["-m", "grasshopper_mcp.bridge"]
   }
   

   This configuration tells Claude Desktop to use the command python -m grasshopper_mcp.bridge to start the MCP server.

5. Start Using Grasshopper with Claude Desktop

   You can now use Claude Desktop to control Grasshopper through natural language commands.

Example Commands

Here are some example commands you can use with Claude Desktop:

• "Create a circle with radius 5 at point (0,0,0)"
• "Connect the circle to a extrude component with a height of 10"
• "Create a grid of points with 5 rows and 5 columns"
• "Apply a random rotation to all selected objects"

Troubleshooting

If you encounter issues, check the following:

1. GH_MCP Component Not Loading

   • Ensure the .gha file is in the correct location
   • In Grasshopper, go to File > Preferences > Libraries and click "Unblock" to unblock new components
   • Restart Rhino and Grasshopper

2. Bridge Server Won't Start

   • If grasshopper-mcp command doesn't work, use python -m grasshopper_mcp.bridge instead
   • Ensure all required Python dependencies are installed
   • Check if port 8080 is already in use by another application

3. Claude Desktop Can't Connect

   • Ensure the bridge server is running
   • Verify you're using the correct connection settings (localhost:8080)
   • Check the console output of the bridge server for any error messages

4. Commands Not Executing

   • Verify the GH_MCP component is on your Grasshopper canvas
   • Check the bridge server console for error messages
   • Ensure Claude Desktop is properly connected to the bridge server

Development

Project Structure

grasshopper-mcp/
├── grasshopper_mcp/       # Python bridge server
│   ├── __init__.py
│   └── bridge.py          # Main bridge server implementation
├── GH_MCP/                # Grasshopper component (C#)
│   └── ...
├── releases/              # Pre-compiled binaries
│   └── GH_MCP.gha         # Compiled Grasshopper component
├── setup.py               # Python package setup
└── README.md              # This file

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

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

Acknowledgments

• Thanks to the Rhino and Grasshopper community for their excellent tools
• Thanks to Anthropic for Claude Desktop and the MCP protocol

Contact

For questions or support, please open an issue on the GitHub repository.