ClaudeBridge

A Fusion 360 add-in that enables Claude to programmatically control Autodesk Fusion 360. Create 3D models through natural language by letting Claude send commands directly to Fusion 360.

Features

• File-based IPC: Simple JSON command/response protocol
• Comprehensive API: Sketches, extrusions, revolves, fillets, chamfers, and more
• Claude Code Integration: Includes a skill for seamless Claude Code usage
• Extensible: Modular command architecture for easy customization

Installation

1. Clone the Repository

git clone https://github.com/your-username/ClaudeBridge.git

2. Install the Add-in

1. Open Fusion 360
2. Create or open a design
3. Press Shift+S to open the Scripts and Add-Ins dialog
4. Go to the Add-Ins tab
5. Click the + button
6. Select Script or add-in from device
7. Navigate to and select the cloned ClaudeBridge repository folder
8. Select ClaudeBridge from the list and click Run

The add-in will now load directly from your repository folder, so any changes you make to the code will be reflected after restarting the add-in.

How It Works

ClaudeBridge uses a file-based IPC (Inter-Process Communication) mechanism:

┌─────────────┐     writes      ┌─────────────────┐
│   Claude    │ ──────────────▶ │  commands.json  │
└─────────────┘                 └────────┬────────┘
                                         │ polls (1s)
                                         ▼
                                ┌─────────────────┐
                                │  ClaudeBridge   │
                                │   (Fusion 360)  │
                                └────────┬────────┘
                                         │ writes
                                         ▼
┌─────────────┐     reads       ┌─────────────────┐
│   Claude    │ ◀────────────── │  results.json   │
└─────────────┘                 └─────────────────┘

Command Format

Write commands to commands.json:

{
  "id": 1,
  "action": "create_sketch",
  "params": {"plane": "xy"}
}

Important: The id must increment with each command. Duplicate IDs are ignored.

Response Format

Results appear in results.json:

{
  "id": 1,
  "success": true,
  "result": {"sketch_index": 0, "message": "Created sketch on xy plane"},
  "error": null
}

Claude Code Skill

ClaudeBridge includes a Claude Code skill in .claude/skills/fusion360/ that enables Claude Code to control Fusion 360 interactively.

Using the Skill

1. Ensure ClaudeBridge is running in Fusion 360
2. In Claude Code, the skill activates automatically when working in this repository
3. Ask Claude to create 3D models: "Create a 5cm cube with rounded edges"

The skill provides Claude with:

• Command reference documentation
• Example workflows
• Best practices for 3D modeling

Available Commands

Session Export

Command	Description
export_session	Export all design data to timestamped folder

Connection

Command	Description
ping	Test connection
message	Display message in Fusion 360

Sketching

Command	Description
create_sketch	Create sketch on plane
create_sketch_on_face	Create sketch on body face
draw_circle	Draw a circle
draw_rectangle	Draw a rectangle
draw_line	Draw a line
draw_polygon	Draw a regular polygon
draw_arc / draw_arc_sweep / draw_arc_three_points	Draw arcs
list_profiles	List available profiles

Sketch Constraints

Command	Description
add_constraint_midpoint	Constrain point to line midpoint
add_constraint_coincident	Constrain point to curve
add_constraint_coincident_points	Constrain two points together
add_constraint_vertical	Make line vertical
add_constraint_horizontal	Make line horizontal
get_sketch_constraints	List all constraints
delete_constraint	Delete a constraint

3D Features

Command	Description
extrude	Extrude a profile
revolve	Revolve around an axis
loft / loft_rails	Create smooth transitions
fillet	Round edges
chamfer	Bevel edges
shell	Hollow out a body

Construction

Command	Description
create_offset_plane	Create plane at Z offset
create_plane_at_angle	Create angled plane

Parameters

Command	Description
set_parameter	Create/update user parameter

Units

All dimensions are in centimeters (Fusion 360's internal unit):

• 1 cm = 10 mm
• For a 50mm dimension, use 5

Architecture

ClaudeBridge/
├── ClaudeBridge.py              # Entry point
├── config.py                    # File paths, settings
├── utils.py                     # JSON utilities
├── core/
│   ├── polling.py               # Background polling thread
│   └── event_handler.py         # Main thread event handler
├── commands/
│   ├── dispatcher.py            # Command routing
│   ├── context.py               # Fusion 360 API abstraction
│   ├── helpers/                 # Shared utilities
│   │   ├── geometry/            # Geometry helpers (bodies, sketches, edges, etc.)
│   │   ├── sketch_curves.py     # Curve accessors
│   │   └── command_utils.py     # Decorators
│   ├── queries/                 # [Deprecated] Use export_session
│   ├── sketch/
│   │   ├── create.py            # Sketch creation
│   │   ├── primitives.py        # Basic shapes
│   │   ├── curves.py            # Arcs
│   │   └── constraints/         # Geometric constraints
│   ├── features/                # 3D operations
│   ├── construction/            # Construction geometry
│   └── export/
│       └── session/             # Session export with collectors
└── .claude/skills/fusion360/    # Claude Code skill

See docs/architecture.md for detailed architecture documentation.

Adding New Commands

1. Choose the appropriate module in commands/
2. Create a handler function:

def my_command(command_id, params, ctx):
    """Description of command."""
    # Implementation using ctx.design, ctx.root, etc.
    write_result(command_id, True, {"message": "Success"})

COMMANDS = {
    "my_command": my_command,
}

3. The command is automatically registered and available

License

MIT License