Render
0.24–0.41 s
Each change, in view
OpenSCAD runs with the Manifold backend. This is the range for the 72 meshes on this page.
MCP serverYour agent drives the window
Ask for the change.
Ask for the change.
Check the slice.
Print.
CoCAD is the fast way to make models for 3D printing. An AI agent changes the OpenSCAD model over MCP. You see the new render and its print layers in seconds, and you catch errors before the printer does.
.deb | also for
The loop
One prompt.
Render, slice, next prompt.
Most of the time on a printable model goes to small changes and checks. CoCAD keeps that loop short. Pick a prompt and watch one turn.
Ready
Why it is fast
The check comes
before the print.
Slice
< 50 ms
Layers, not a slicer session
See walls, infill and skin at real line width. You do not export or open a slicer for a first check.
Agent
16 tools
It sees what you see
The agent reads the render state, the OpenSCAD log, open edges and slice data. Then it fixes what it finds.
Finish
STL 3MF STEP
Done means a file
Export from the window or through the agent. Render a studio photo of the part if you want one.
MCP server Next release
Your agent works
in the open window.
The client starts cocad mcp. Each tool call goes to the open window, so you see every change as it happens.
claude_desktop_config.json
{
"mcpServers": {
"cocad": {
"command": "cocad",
"args": ["mcp"]
}
}
}Claude Code
claude mcp add cocad -- cocad mcp| get_state | File, render status, last error, mesh data, OpenSCAD log |
|---|---|
| get_params | All Customizer parameters with limits and options |
| get_source | Source of the .scad file |
| view_model | Render an image and return it to the client |
| open_model | Open a file. Starts the app when it is not running |
| set_params reset_params | Change or reset parameters, then render |
| render | Run OpenSCAD again |
| slice | Layers, filament, weight and a rough print time |
| export_model | Write STL, 3MF or STEP |
| save_photo | Write a path traced PNG |
| set_view | Tab, camera, wireframe, grid and slice layer |
| load_parameter_set save_parameter_set | Load or save a named set |
| list_windows select_window | Choose a window when more than one is open |
- Limits apply. One bad value rejects the whole call.
- No stale output. Export and photo fail when the last render failed.
- No overwrite. Files stay unless the call sets
overwrite. - Local only. Each window listens on 127.0.0.1 and needs a random token.
Tour
The rest of the app.
Real screenshots of the example models.
Slice preview. Walls, infill and skin as round strands, with a layer slider and a time, length and weight estimate.
Photo render
Happy with the slice?
See the part.
The path tracer makes a studio photo of the current view. The agent can run it too, or you can use the CLI.
Command line
cocad photo model.scad -o model.png --size 1600x1200 --samples 256 --color ff9300 --finish satin --layer-linesFeatures
Also without an agent
Customizer panel
It reads the same comments as OpenSCAD. The model renders again when you change a value.
Live reload
Keep your editor open. When the file changes on disk, the model reloads and your values stay.
Parameter sets
Save named sets in the OpenSCAD
.jsonformat.Slice preview
Walls, infill and skin, with a time, length and weight estimate. It writes no G-code.
Mesh check
Size, volume, triangles and open edges. Back faces show in purple.
Real STEP export
AP214 with planar faces. A closed mesh becomes one solid that CAD tools can edit.
3MF with parameters
The parameter values go in the metadata of the file.
Batch CLI
Run
export,sliceandphotowithout the window.Three systems
Linux, Windows and macOS, with dark and light themes.
You also need OpenSCAD
Install a development snapshot. It has the Manifold backend. The 2021 release also works, but a model that takes 13 s with CGAL can take 0.3 s with Manifold.
Older versions and release notes are on GitHub releases.
FAQ
Asked first
Which agents work with it?
Claude Desktop, Claude Code and other MCP clients. The client talks to cocad mcp and that process talks to the open window.
Can the agent change the geometry, or only the parameters?
Both. The agent reads the source with get_source. A client that can write files can edit the .scad file, and the window reloads it. set_params changes Customizer values with no file edit.
Does it replace my slicer?
No. The slice is for preview only. It has no travel moves, supports or bridges, and it does not write G-code. Export a 3MF or STL for your slicer.
What errors does the check show?
The mesh check shows open edges and back faces. The slice view shows each layer, so you can see gaps, thin walls and details that vanish. The OpenSCAD console shows script errors. The agent reads the same log and data.
Does my model leave my computer?
CoCAD has no account, no server and no telemetry. The MCP server listens on 127.0.0.1 only. Your AI client sends what it reads to its own model provider, so pick the client with that in mind. See the privacy policy.
Do I need an agent?
No. Open a file, move the sliders and use your own editor. The app works the same way. To turn the MCP server off, use File > Settings.
What does it cost?
Nothing. It is open source under the MIT License.