Fusion 360 MCP Server

Control Autodesk Fusion 360 with Claude AI through the Model Context Protocol (MCP).

What This Does

Ask Claude to create a part, watch it appear in Fusion 360

This MCP server lets Claude AI directly control Fusion 360 to: lets Claude AI directly control Fusion 360 to:

• Create 3D sketches, extrusions, revolves, and sweeps
• Build multi-component assemblies with proper positioning
• Apply fillets, chamfers, shells, and patterns
• Export to STL, STEP, and 3MF formats
• Measure geometry and verify designs

Example prompt: “Create a 50mm cube with 5mm rounded edges” → Claude creates it directly in Fusion 360.

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Quick Start (5 minutes)

Prerequisites

• Autodesk Fusion 360 (free for personal use)
• Claude Desktop app with MCP support
• Python 3.10+ with pip

Step 1: Install the MCP Server

# Install the MCP framework
pip install mcp

# Clone this repository (or download ZIP)
git clone https://github.com/YOUR_USERNAME/fusion360-mcp.git
cd fusion360-mcp

Step 2: Install the Fusion 360 Add-in

1. Open Fusion 360
2. Go to Utilities → ADD-INS (or press Shift+S)
3. Click Add-Ins tab → Green Plus (+) button
4. Navigate to the fusion-addin folder from this repo
5. Select FusionMCP folder → Click Open
6. Check Run on Startup → Click Run

You should see: “Fusion MCP Started! Listening at: C:\Users.…\fusion_mcp_comm”

Successfully installed FusionMCP add-in

Step 3: Configure Claude Desktop

Edit your Claude Desktop config file:

Windows: %APPDATA%\Claude\claude_desktop_config.json
Mac: ~/Library/Application Support/Claude/claude_desktop_config.json

Add this to the mcpServers section:

{
  "mcpServers": {
    "fusion360": {
      "command": "python",
      "args": ["C:/path/to/fusion360-mcp/mcp-server/fusion360_mcp_server.py"]
    }
  }
}

Note: Use forward slashes in the path, even on Windows.

Step 4: Add the Skill File (Recommended)

For best results, create a Claude Project and paste the contents of docs/SKILL.md into the Project Instructions. This teaches Claude:

• Fusion 360 coordinate system rules
• Unit conventions (everything in centimeters!)
• Best practices for assemblies
• Common pitfalls to avoid

For advanced spatial reasoning, also include docs/SPATIAL_AWARENESS.md. This teaches Claude:

• How to verify geometry placement BEFORE operations
• Coordinate mapping between sketch planes and world space
• The critical Z-negation rule for XZ/YZ planes
• Pre/post operation verification protocols

Step 5: Restart and Test

1. Restart Claude Desktop
2. Open Fusion 360 (ensure the add-in is running)
3. Ask Claude: “Create a simple box that is 5cm x 3cm x 2cm”

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How It Works

┌─────────────┠    MCP      ┌─────────────────────┠   File     ┌─────────────â”
│   Claude    │ â†â†’ Protocol → │  MCP Server         │ â†â†’ System â†â†’ │  Fusion 360 │
│   Desktop   │              │  (fusion360_mcp_    │             │  Add-in     │
│             │              │   server.py)        │             │  (FusionMCP)│
└─────────────┘              └─────────────────────┘             └─────────────┘

1. Claude sends commands via MCP protocol
2. MCP server writes command to ~/fusion_mcp_comm/command_*.json
3. Fusion add-in polls for commands, executes them via Fusion API
4. Results written to ~/fusion_mcp_comm/response_*.json
5. MCP server returns result to Claude

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Available Tools

See docs/TOOL_REFERENCE.md for complete API documentation.

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Important: Units Are in Centimeters!

âš ï¸ All dimensions in the MCP are in CENTIMETERS, not millimeters.

This is the most common source of errors. A value of 50 means 50 cm (half a meter)!

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Project Structure

fusion360-mcp/
├── README.md                 # This file
├── LICENSE                   # MIT License
├── mcp-server/
│   └── fusion360_mcp_server.py   # MCP server (run by Claude Desktop)
├── fusion-addin/
│   ├── FusionMCP.py          # Fusion 360 add-in code
│   └── FusionMCP.manifest    # Add-in manifest
├── docs/
│   ├── SKILL.md              # Claude Project instructions
│   ├── SPATIAL_AWARENESS.md  # 3D coordinate system & verification
│   ├── TOOL_REFERENCE.md     # Complete API reference
│   └── KNOWN_ISSUES.md       # Common pitfalls and solutions
└── examples/
    └── getting_started.md    # Tutorial examples

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Example Workflows

Creating a Simple Part

“Create a 5cm cube with 2mm rounded edges”

Complex Assembly

Multi-component assembly with proper positioning

Export Ready Files

Direct export to STL, STEP, and 3MF formats

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Troubleshooting

“Timeout after 45s” Error

• Fusion 360 is not running, OR
• The FusionMCP add-in is not started
• Fix: Open Fusion 360 → Utilities → Add-Ins → Run FusionMCP

Claude doesn’t see the Fusion 360 tools

• MCP server path is wrong in config
• Python can’t find the mcp package
• Fix: Verify path uses forward slashes, run pip install mcp

Dimensions are way too big/small

• You’re using millimeters instead of centimeters
• Fix: Divide all mm values by 10

Add-in won’t install

• Folder structure is wrong
• Fix: The add-in folder must contain both .py and .manifest files

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Contributing

Contributions welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Submit a pull request

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License

MIT License - see LICENSE file.

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Credits

• MCP Server & Add-in developed with Claude AI (Anthropic)
• Uses the Model Context Protocol by Anthropic
• Built for Autodesk Fusion 360