redswoop/scad-workbench

A workbench for designing 3D-printable parts in OpenSCAD together with an AI coding agent. It was built around Claude Code, and the viewer and tools are also useful on their own.
OpenSCAD models are code, which an agent writes well, but neither of you can see what the other means. This repo is the shared surface:
- **viewer/**: a browser viewer that rebuilds every part on save. Per-part colours and groups, a parameter panel read from the .scad file, section cuts with hatched caps (overlapping parts show in red), bounding-box sizes, reference photos, and notes you draw on the render that the agent can read back with the parts and millimetre coordinates under each stroke.
- **tools/**: command-line checks the agent runs instead of eyeballing: collision tables across poses, STL facts (volume, watertightness, shell count), parameter write-back, volume comparison against a reference mesh, STL cross-sections, 3MF and Shapr3D readers.
- **lib/**: shared OpenSCAD modules (printable fillets, sweeps, teardrop holes, settled clearances).
- **template/**: the skeleton of a model folder: model, viewer manifest, print layout, collision pairs, tolerance coupon, export scripts, README.
- **.claude/skills/openscad/**: the playbook that tells Claude how to use all of the above.
Requirements
- macOS or Linux. Windows is untested (the tools are bash and Python; WSL should work).
- **OpenSCAD, a development snapshot.** The 2021.01 stable release has no Manifold backend and will not work. macOS: brew install --cask openscad@snapshot. Linux: a nightly AppImage or package from openscad.org/downloads. It must be on PATH as openscad, or set OPENSCAD=/path/to/openscad.
- Bun for the viewer.
- Python 3 and uv for the tools. stlinfo.py, voxcmp.py and shapr_dump.py are uv run --script files that fetch their own dependencies (numpy, msgpack); the collision check and the export scripts call stlinfo.py.
- Claude Code, if you want the agent side.
Quick start
Open http://127.0.0.1:5180/examples/hinge_box/. Then:
- Edit examples/hinge_box/hinge_box.scad and save: the page rebuilds.
- Change lid_deg in the parameter panel and press Apply.
- Press s for a section cut and drag the hatched face.
- Run the collision table: tools/check.sh examples/hinge_box/check.scad 'lid_deg=0' 'lid_deg=90' 'lid_deg=180'
The viewer listens on localhost only. HOST=0.0.0.0 bun run dev opens it to your network; the API has no authentication, so do that only on a network you trust.
Your own model
This copies template/ to bracket/, makes it its own git repo (this repo ignores model folders, so your designs stay yours), and it shows up at http://127.0.0.1:5180/bracket/. Something with several assemblies is one repo with a subfolder each: tools/new-model.sh boat/hull, tools/new-model.sh boat/hatch.
With Claude Code
Start claude in the repo root so CLAUDE.md and the openscad skill load, and ask for a part. The skill has Claude keep every dimension a named parameter, look at its own work in the viewer, run the collision pairs at the design extremes, print a tolerance coupon before the real parts, and leave each model's README.md as a handoff for the next session. A browser tool (Claude in Chrome or similar) lets it take screenshots of the viewer and drive it through window.viewer.