🛠️ MCP-FreeCAD Integration

Status: Active Development - Clean, organized codebase with multiple connection methods and comprehensive tool providers.

This project provides a robust integration between AI assistants and FreeCAD CAD software using the Model Context Protocol (MCP). It allows external applications to interact with FreeCAD through a standardized interface, offering multiple connection methods and specialized tools.

🤖 AI Provider Models (2025)

The MCP-FreeCAD integration supports multiple AI providers with the latest 2025 models. Choose the right model for your specific use case:

OpenAI Models

Production Models:

• gpt-4o - Default multimodal model (text, image, audio)

  • Context: 128K tokens

  • Pricing: ~$5 per 1M input tokens

  • Best for: General CAD tasks, multimodal interactions

• gpt-4.1 - Next-generation with 1M token context

  • Features: Text, Image, Audio, Video support

  • Pricing: ~$2.5 per 1M input tokens

  • Best for: Complex CAD projects, large document analysis

• gpt-4-turbo - Fast, cost-effective

  • Context: 128K tokens

  • Best for: High-volume operations, batch processing

Reasoning Models:

• o3 - Advanced reasoning for complex CAD logic

  • Pricing: ~$10 per 1M input tokens

  • Best for: Complex geometry calculations, design optimization

• o4-mini / o4-mini-high - Cost-effective reasoning

  • Pricing: ~$0.15 per 1M input tokens

  • Best for: Simple calculations, quick iterations

Anthropic Claude Models

Claude 4 Series (2025):

• claude-opus-4 - Most advanced model

  • Max Context: 200K tokens

  • Pricing: $15/$75 per million tokens (input/output)

  • Features: Extended thinking, tool use, memory handling

  • Best for: Complex CAD workflows, autonomous design tasks

• claude-sonnet-4 - Balanced efficiency

  • Max Context: 200K tokens

  • Pricing: $3/$15 per million tokens

  • Features: Superior coding, hybrid reasoning

  • Best for: General CAD operations, scripting assistance

• claude-haiku-3.5 - Fast, lightweight

  • Best for: Quick queries, simple operations

Google AI Models

Gemini 2.5 Series (Latest):

• gemini-2.5-pro-preview-05-06 - Most advanced

  • Context: 1M tokens

  • Features: Enhanced reasoning, thinking mode

  • Best for: Complex CAD analysis, large assemblies

• gemini-2.5-flash-preview-04-17 - Performance optimized

  • Features: Adaptive thinking, cost-effective

  • Best for: Balanced performance and cost

Gemini 2.0 Series (Stable):

• gemini-2.0-flash-001 - Production ready

  • Features: 2x faster than Gemini 1.5 Pro

  • Best for: Real-time CAD assistance

• gemini-2.0-flash-lite - Cost-optimized

  • Best for: High-volume, simple operations

OpenRouter (Unified Access)

OpenRouter provides access to all models through a single API:

Model Format: provider/model-name

Popular Models:

• anthropic/claude-sonnet-4 - Recommended general use

• openai/gpt-4o - OpenAI's flagship

• google/gemini-2.5-pro-preview - Google's latest

Free Models (50-1000 requests/day):

• deepseek/deepseek-r1 - Advanced reasoning

• deepseek/deepseek-v3 - General purpose

• google/gemini-2.5-flash-preview - Google free tier

Model Selection Guide

Configuration Example

{
  "providers": {
    "anthropic": {
      "enabled": true,
      "model": "claude-sonnet-4",
      "thinking_mode": true,
      "max_tokens": 64000
    },
    "openai": {
      "enabled": true,
      "model": "gpt-4o",
      "max_tokens": 32000
    },
    "google": {
      "enabled": true,
      "model": "gemini-2.0-flash-001",
      "thinking_mode": true
    },
    "openrouter": {
      "enabled": true,
      "model": "anthropic/claude-sonnet-4",
      "free_models": ["deepseek/deepseek-r1"]
    }
  }
}

API Usage Examples

# Using specific provider
from freecad_ai import CADAssistant

# Initialize with Claude Sonnet 4
assistant = CADAssistant(provider="anthropic", model="claude-sonnet-4")

# Create complex geometry
result = assistant.generate_cad_script(
    "Create a parametric gear with 20 teeth, 5mm module, and 20° pressure angle"
)

# Using OpenRouter for cost optimization
assistant_free = CADAssistant(
    provider="openrouter", 
    model="deepseek/deepseek-r1"
)

# Quick operations with free model
result = assistant_free.create_primitive("box", length=10, width=5, height=3)

Related MCP server: FreeCAD MCP

🚀 Quick Start

Option 1: FreeCAD Addon (Recommended for Users)

For the best user experience with GUI integration:

📦 FreeCAD MCP Integration Addon

• 🧠 Claude 4 with Thinking Mode - Advanced AI reasoning

• 🤖 Multi-Provider Support - Claude, Gemini, OpenRouter with 13+ models

• 🎨 Modern GUI - Professional tabbed interface

• 🔗 Universal Connections - All MCP connection methods

• 📊 Performance Monitoring - Real-time diagnostics

Option 2: MCP Server (For Developers/Integration)

# Clone the repository
git clone https://github.com/jango-blockchained/mcp-freecad.git
cd mcp-freecad

# Install dependencies
pip install -r requirements.txt

# Start the MCP server
python mcp_server.py

# Or with FastMCP mode (lightweight, ideal for Cursor IDE)
python mcp_server.py --mode fastmcp

# Or with custom config and debug logging
python mcp_server.py --config my_config.json --debug

python -m src.mcp_freecad.main --config my_config.json --debug

### Option 3: FastMCP Server (Cursor IDE & Latest Best Practices)

**✨ NEW: Updated to FastMCP 2.13.0.2** - Modern, declarative MCP server implementation.

```bash
# Start the FastMCP server for Cursor IDE
python cursor_mcp_server.py

# Or run the example to see available tools
python example_fastmcp_usage.py --all

Key Features:

• 🎯 Declarative API - Simple @mcp.tool() and @mcp.resource() decorators

• 🔒 Type Safe - Automatic schema generation from type hints

• 🚀 Best Practices - Follows FastMCP 2.13 recommended patterns

• ✅ Well Tested - Comprehensive test suite with 100% pass rate

• 📚 Great Documentation - See FASTMCP_IMPLEMENTATION.md

Available Tools:

• test_connection - Test FreeCAD connectivity

• create_box - Create box primitives

• create_cylinder - Create cylinders

• create_sphere - Create spheres

• create_document - Manage FreeCAD documents

Resources:

• freecad://status - Get server status and FreeCAD availability

For detailed usage, see the FastMCP Implementation Guide.

🏗️ Architecture Overview

Core Components

src/mcp_freecad/
├── main.py                 # Main entry point
├── __init__.py            # Package exports and registry
├── client/                # FreeCAD connection management
│   └── freecad_connection_manager.py
├── server/                # MCP server implementation
│   └── freecad_mcp_server.py
├── tools/                 # Tool providers
│   ├── base.py           # Base tool provider class
│   ├── primitives.py     # Primitive shapes (box, cylinder, etc.)
│   ├── model_manipulation.py # Transform, boolean ops, etc.
│   ├── export_import.py  # File format handling
│   ├── measurement.py    # Analysis tools
│   └── code_generator.py # Code generation
├── core/                  # Core infrastructure
│   ├── server.py         # FastAPI-based server
│   ├── cache.py          # Resource caching
│   ├── diagnostics.py    # Performance monitoring
│   └── recovery.py       # Connection recovery
└── connections/           # Connection backends

Connection Methods

The system supports multiple ways to connect to FreeCAD:

1. 🚀 Launcher (Recommended) - Uses AppImage with AppRun

2. 🔌 Server - Socket-based connection to FreeCAD server

3. 🌉 Bridge - CLI-based connection using FreeCAD executable

4. 📡 RPC - XML-RPC connection to FreeCAD

5. 📦 Wrapper - Subprocess wrapper connection

6. 🎭 Mock - For testing without FreeCAD

🛠️ Available Tools

Primitive Creation

• create_box - Create box primitives

• create_cylinder - Create cylinders

• create_sphere - Create spheres

• create_cone - Create cones

Model Manipulation

• transform - Move, rotate objects

• boolean_operation - Union, difference, intersection

• fillet_edge - Round edges

• chamfer_edge - Chamfer edges

• mirror - Mirror objects across planes

• scale - Scale objects uniformly or non-uniformly

Document Management

• create_document - Create new documents

• list_documents - List open documents

• list_objects - List objects in documents

Export/Import

• export_stl - Export to STL format

• Additional formats coming soon

📋 Usage Examples

Python API

from src.mcp_freecad import FreeCADConnection, PrimitiveToolProvider

# Create connection (auto-selects best method)
fc = FreeCADConnection(auto_connect=True)

if fc.is_connected():
    print(f"Connected via: {fc.get_connection_type()}")
    
    # Create a document
    doc_name = fc.create_document("MyProject")
    
    # Create objects
    box = fc.create_box(length=20, width=10, height=5)
    cylinder = fc.create_cylinder(radius=3, height=10)
    
    # Export
    fc.export_stl(box, "my_box.stl")

Tool Provider Usage

from src.mcp_freecad.tools.primitives import PrimitiveToolProvider

# Initialize tool provider
primitives = PrimitiveToolProvider()

# Execute tools
result = await primitives.execute_tool("create_box", {
    "length": 10.0,
    "width": 5.0, 
    "height": 3.0
})

print(f"Created: {result.result['object_id']}")

MCP Server Integration

from src.mcp_freecad.core.server import MCPServer
from src.mcp_freecad import TOOL_PROVIDERS

# Setup server
server = MCPServer()

# Register tool providers
server.register_tool("primitives", TOOL_PROVIDERS["primitives"]())
server.register_tool("model_manipulation", TOOL_PROVIDERS["model_manipulation"]())

# Initialize and run
await server.initialize()

⚙️ Configuration

Basic Configuration (config.json)

{
  "server": {
    "name": "mcp-freecad-server",
    "version": "0.7.11"
  },
  "freecad": {
    "connection_method": "auto",
    "host": "localhost",
    "port": 12345,
    "freecad_path": "freecad"
  },
  "tools": {
    "enable_primitives": true,
    "enable_model_manipulation": true,
    "enable_export_import": true
  }
}

Connection Method Configuration

{
  "freecad": {
    "connection_method": "launcher",
    "use_apprun": true,
    "apprun_path": "/path/to/squashfs-root/AppRun",
    "script_path": "/path/to/freecad_launcher_script.py"
  }
}

🔧 Development

Project Structure

• src/mcp_freecad/ - Main package

• freecad-ai/ - FreeCAD GUI addon

• tests/ - Test suite

• docs/ - Documentation

• scripts/ - Setup and utility scripts

Adding New Tools

1. Create a new tool provider in src/mcp_freecad/tools/

2. Inherit from ToolProvider base class

3. Implement required methods (tool_schema, execute_tool)

4. Register in TOOL_PROVIDERS in __init__.py

from .base import ToolProvider, ToolResult, ToolSchema

class MyToolProvider(ToolProvider):
    @property
    def tool_schema(self) -> ToolSchema:
        return ToolSchema(
            name="my_tool",
            description="My custom tool",
            parameters={...},
            returns={...}
        )
    
    async def execute_tool(self, tool_id: str, params: Dict[str, Any]) -> ToolResult:
        # Implementation
        return self.format_result(status="success", result=result)

Testing

# Run tests
python -m pytest tests/

# Run with coverage
python -m pytest tests/ --cov=src --cov-report=html

# Run specific test
python -m pytest tests/test_primitives.py -v

🐳 Docker Support

# Build and run with Docker Compose
docker compose up

# Build from scratch
docker compose build --no-cache
docker compose up

📚 Documentation

• FreeCAD Integration Guide

• Connection Methods

• Tool Development

• Configuration Reference

🤝 Contributing

1. Fork the repository

2. Create a feature branch

3. Make your changes

4. Add tests

5. Submit a pull request

📄 License

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

🙏 Acknowledgments

• FreeCAD development team for the excellent CAD software

• Anthropic for the Model Context Protocol (MCP) framework

• Contributors and community members