Blender MCP (Model Context Protocol)

A Blender addon that enables AI assistants (like Claude) to interact with Blender through the Model Context Protocol (MCP).

Installation

1. Install the Blender Addon

1. Download or clone this repository

2. Copy the entire src/blender_mcp/addon/ directory to your Blender addons folder:

   • Windows: %APPDATA%\Blender Foundation\Blender\4.x\scripts\addons\
   • macOS: ~/Library/Application Support/Blender/4.x/scripts/addons/
   • Linux: ~/.config/blender/4.x/scripts/addons/

3. Rename the copied directory from addon to blender_mcp

4. Open Blender and go to Edit > Preferences > Add-ons

5. Search for "Blender MCP" and enable the addon

2. Install the MCP Server

The MCP server runs outside Blender and communicates with it via sockets.

1. Install Python dependencies:

   pip install mcp-server-fastmcp

2. Or if using the provided virtual environment:

   # Activate the virtual environment
   source .venv/bin/activate  # On Windows: .venv\Scripts\activate
   
   # Install dependencies
   pip install -r requirements.txt

3. Configure Your MCP Client

Add the Blender MCP server to your MCP client configuration (e.g., Claude Desktop):

{
  "mcpServers": {
    "blender": {
      "command": "python",
      "args": ["-m", "blender_mcp.server"],
      "env": {
        "BLENDER_HOST": "localhost",
        "BLENDER_PORT": "9876"
      }
    }
  }
}

Usage

1. Start Blender and enable the Blender MCP addon
2. Start your MCP client (Claude Desktop, etc.) with the server configured
3. In Blender, click the "Connect to MCP server" button in the BlenderMCP panel (N-panel > BlenderMCP)
4. Use Claude to interact with Blender through natural language commands

Features

Core Tools

• Scene Information: Get details about objects, materials, and scene structure
• Object Manipulation: Query and modify 3D objects
• Viewport Screenshots: Capture Blender's 3D viewport
• Code Execution: Run Python code directly in Blender

Template Engine

• Template Management: Create, save, and reuse complex operations
• Dynamic Overrides: Apply templates with parameter modifications
• Template Search: Discover templates by tags and categories
• Usage Analytics: Track template performance and success rates
• Version Control: Optional Git versioning for template evolution

Asset Integrations

• PolyHaven: Download HDRIs, textures, and 3D models
• Sketchfab: Search and download 3D models
• Hyper3D Rodin: Generate 3D models from text or images

Configuration

Blender Addon Settings

• Port: Socket port for communication (default: 9876)
• PolyHaven: Enable/disable PolyHaven integration
• Hyper3D: Configure API keys and modes
• Sketchfab: Configure API key for model downloads

Environment Variables

• BLENDER_HOST: Host address (default: localhost)
• BLENDER_PORT: Port number (default: 9876)

Architecture

The system consists of two main components:

1. Blender Addon (src/blender_mcp/addon/): Runs inside Blender, handles UI and executes Blender operations
2. MCP Server (src/blender_mcp/server/): Runs outside Blender, provides MCP tools and manages communication

Development

Project Structure

src/blender_mcp/
├── addon/              # Blender addon code
│   ├── handlers.py     # Base command handlers
│   ├── polyhaven_handlers.py  # PolyHaven integration
│   ├── hyper3d_handlers.py    # Hyper3D integration
│   ├── sketchfab_handlers.py  # Sketchfab integration
│   ├── ui.py           # Blender UI components
│   ├── server.py       # Socket server for addon
│   └── __main__.py     # Addon registration
└── server/             # MCP server code
    ├── connection.py   # MCP server and socket client
    ├── tools.py        # Core Blender tools
    ├── integrations.py # Integration tools
    ├── template_engine.py     # Template storage and management
    ├── template_tools.py      # MCP tools for templates
    ├── prompts.py      # MCP prompts
    └── __main__.py     # Server entry point
templates/              # Template storage directory
├── template_name.json  # Template definitions
└── analytics.json      # Usage statistics

Running Tests

# Test server modules
python -m pytest tests/

# Or manually test imports
python -c "from src.blender_mcp.server.connection import mcp; print('OK')"

Troubleshooting

Connection Issues

• Ensure the Blender addon is enabled and running
• Check that the port numbers match between client and server
• Verify firewall settings allow socket connections

Integration Issues

• Check API keys are properly configured in Blender
• Ensure internet connectivity for external services
• Review Blender console for error messages

Performance

• Large scenes may take time to process
• Asset downloads depend on internet speed
• 3D generation can take several minutes

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test thoroughly
5. Submit a pull request

License

See LICENSE file for details.