Fusion MCP Integration

https://github.com/user-attachments/assets/46c8140e-377d-4618-a304-03861cb3d7d9

🎯 About

Fusion MCP Integration bridges AI assistants with Autodesk Fusion 360 through the Model Context Protocol (MCP). This enables:

• ✨ Conversational CAD - Create 3D models using natural language
• 🤖 AI-Driven Automation - Automate repetitive modeling tasks
• 🔧 Parametric Control - Dynamically modify design parameters
• 🎓 Accessible CAD - Lower the barrier for non-CAD users

Note: This is designed as an assistive tool and educational project, not a replacement for professional CAD workflows. Projects like this can assist people with no experience in CAD workflows.

Goal: Enable conversational CAD and AI-driven automation in Fusion.

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Setup

I highly recommend to do everything inside Visual Studio Code or an other IDE

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Requirements

Requirement	Link
Python 3.10+	https://python.org
Autodesk Fusion 360	https://autodesk.com/fusion360
Claude Desktop	https://claude.ai/download
VS Code	https://code.visualstudio.com

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Clone Repository

git clone https://github.com/JustusBraitinger/FusionMCP

Important: Do NOT start the Add-In yet.

Install Python Dependencies

cd Server
python -m venv venv

Activate venv

Windows PowerShell

.\venv\Scripts\Activate

Install packages

pip install -r requirements.txt
pip install "mcp[cli]"

Installing the MCP Add-In for Fusion 360

cd ..
python Install_Addin.py

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Connect to Claude

The most simple way to add the MCP-Server to Claude Desktop is to run following command:

cd Server
uv run mcp install MCP_Server.py

The output should be like this:

[11/13/25 08:42:37] INFO     Added server 'Fusion' to Claude config
                    INFO     Successfully installed Fusion in Claude app                                                                                                                                                               

Alternative

Modify Claude Config

In Claude Desktop go to:
Settings → Developer → Edit Config

Add this block (change the path for your system):

{
  "mcpServers": {
    "FusionMCP": {
      "command": "uv",
      "args": [
        "--directory",
        "C:\\Path\\to\\FusionMCP\\Server",
        "run",
        "MCP_Server.py"
      ]
    }
  }
}

Note: Windows paths require double backslashes \\

Using the MCP in Claude

1. Restart Claude if needed (force close if not visible)
2. Click ➕ Add (bottom left of chat)
3. Select Add from Fusion
4. Choose a Fusion MCP prompt

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Use MCP in VS Code (Copilot)

Create or edit the file:

%APPDATA%\Code\User\globalStorage\github.copilot-chat\mcp.json

Paste:

{
  "servers": {
    "FusionMCP": {
      "url": "http://127.0.0.1:8000/sse",
      "type": "http"
    }
  },
  "inputs": []
}

Alternative Setup in VS Code

1. Press CTRL + SHIFT + P → search MCP → choose:
2. Add MCP
3. HTTP
4. Enter:
5. Name your MCP FusionMCP!!

http://127.0.0.1:8000/sse

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Try It Out 😄

Activate the Fusion Addin inside Fusion

Configured in VS-Code:

Start the server:

python MCP_Server.py

Then type

/mcp.FusionMCP

Now you will see a list of predetermined Prompts.

Configured in Claude

Just open Claude, an ask for the FusionMCP

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🛠️ Available Tools

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✏️ Sketching & Creation Tools

Tool	Description
Draw 2D circle	Draws a 2D circle at a specified position and plane.
Ellipsie	Generates an ellipse (elliptical curve) in the sketching plane.
Draw lines	Creates a polyline (multiple connected lines) as a sketch.
Draw one line	Draws a single line between two 3D points.
3-Point Arc	Draws a circular arc based on three defined points.
Spline	Draws a Spline curve through a list of 3D points (used for sweep path).
Draw box	Creates a box (solid body) with definable dimensions and position.
Draw cylinder	Draws a cylinder (solid body).
Draw text	Draws a text and extrudes it with given values
Draw Witzenmann logo	A fun demo function for creating the Witzenmann logo.

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⚙️ Feature & Modification Tools

Tool	Description
Extrude	Extrudes the last active sketch by a given value to create a body.
Revolve	Creates a revolved body by revolving a profile around an axis.
Sweep	Executes a sweep feature using the previously created profile and spline path.
Loft	Creates a complex body by lofting between a defined number of previously created sketches.
Thin extrusion	Creates a thin-walled extrusion (extrusion with constant wall thickness).
Cut extrude	Removes material from a body by cutting a sketch (as a hole/pocket).
Draw holes	Creates Counterbore holes at specified points on a surface (faceindex).
Fillet edges	Rounds sharp edges with a defined radius (fillet).
Shell body	Hollows out the body, leaving a uniform wall thickness.
Circular pattern	Creates a circular pattern (array) of features or bodies around an axis.
Rectangular pattern	Creates a rectangular pattern of a body

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📏 Analysis & Control

Tool	Description
Count	Counts the total number of all model parameters.
List parameters	Lists all defined model parameters in detail.
Change parameter	Changes the value of an existing named parameter in the model.
Test connection	Tests the communication link to the Fusion 360 server.
Undo	Undoes the last operation in Fusion 360.
Delete all	Deletes all objects in the current Fusion 360 session (destroy).

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💾 Export

Tool	Description
Export STEP	Exports the model as a STEP file.
Export STL	Exports the model as an STL file.

Architecture

Server.py

• Defines MCP server, tools, and prompts
• Handles HTTP calls to Fusion add-in

MCP.py

• Fusion Add-in
• Because the Fusion API is not thread-safe, this uses:
  • Custom event handler
  • Task queue

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Why This Architecture?

The Fusion 360 API is not thread-safe and requires all operations to run on the main UI thread. Our solution:

1. Event-Driven Design - Use Fusion's CustomEvent system
2. Task Queue - Queue operations for sequential execution
3. Async Bridge - HTTP server handles async MCP requests

Security Considerations 🔒

• Local execution → safe by default
• Currently HTTP (OK locally, insecure on networks)
• Validate tool inputs to avoid prompt injection
• Real security depends on tool implementation

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This is NOT

• ❌ A production-ready tool
• ❌ A replacement for professional CAD software
• ❌ Suitable for critical engineering work
• ❌ Officially supported by Autodesk

This IS

• ✅ A proof-of-concept
• ✅ An educational project
• ✅ A demonstration of MCP capabilities
• ✅ A tool for rapid prototyping and learning

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This is a proof-of-concept, not production software.

Note

This Fusion MCP implementation uses hard coded Tools, instead of trusting on
the training of the LLM's. I chose this, because I wanted to test how far I can come

Contact

justus@braitinger.org