CAD Studio

Describe a part, get a printable model. A native macOS CAD studio powered by the coding agent on your Mac (Claude Code or Codex) and build123d.

Type "a print-in-place planetary gearbox with four colors, animated with real gear ratios" and CAD Studio has your coding agent write a parametric model.py, run it with build123d and hand you a 3D model, an ISO technical drawing and files ready for your slicer. Every change is a new version you can go back to.

CAD Studio demo

Website · ▶︎ Watch the narrated demo (MP4, with sound)

Features

Chat with an agent that writes and fixes parametric build123d scripts for you
Live 3D viewer with orbit, zoom, pan, grid, wireframe and multi-color 3MF parts
Measure distances and cut sections through the model
Animate mechanisms with a physics simulation (masses, springs, friction) and per-frame collision checks
Multi-part models: assembled, exploded or print-plate view, show, hide or keep parts together
Print plate with every part oriented and laid out for printing (plate.3mf, opened in your slicer)
Floating parameter panel with sliders: tweak dimensions without calling the agent
ISO technical drawings (first-angle projection): assembly with parts list plus one sheet per part, as a multi-page PDF
Version history: jump back to any generation, chat and context included, and compare versions in 3D
Attach or paste (⌘V) reference images, sketches, PDFs and STEP/STL files to the chat
Export STEP, 3MF, STL, PDF drawing and model.py as one ZIP
Printer-aware design rules for FDM, multi-material, resin and SLS, in mm, cm, m or inches
Drag panels anywhere: chat left, right or at the bottom, layout saved per project
English, Italian, German and French

Screenshots

Every screenshot below is from the same project: a print-in-place planetary gearbox, from the first launch to version 2.

Set up once, then describe your part. Pick your printer and units on first launch, create a project and type what you need.

First launch	Describe the part

The agent at work	The finished gearbox

Parts, motion and drawings. Explode the assembly, play the simulated motion and flip through the drawing sheets.

Exploded view	Simulated motion

Edit parameters without the agent	Measure distances

Section view	One sheet per part

Ask for a change: version 2	Compare with version 1

Chat on the right	Chat at the bottom

Quick Start

Prerequisites

macOS 15 or later
Claude Code signed in (run claude once in Terminal), or Codex CLI signed in (codex login); pick one in Settings → Agent
uv or Python 3.10–3.13, used to install build123d on first launch

Download

Grab CADStudio.dmg from the latest release and drag CAD Studio into Applications. The app isn't notarized, so the first time macOS blocks it: open System Settings → Privacy & Security and click Open Anyway, or run:

xattr -dr com.apple.quarantine "/Applications/CAD Studio.app"

Build from source (needs Xcode 16 or later)

git clone https://github.com/filippofinke/cad-studio.git
cd cad-studio
./build.sh --install

This builds a universal CAD Studio.app, copies it to /Applications and launches it. ./build.sh --dmg builds build/CADStudio.dmg. You can also open CADStudio.xcodeproj and press ⌘R.

How it works

Every project is a folder. CAD Studio runs the agent installed on your Mac in headless mode (claude -p --output-format stream-json, or codex exec --json in its workspace sandbox) inside that folder, with a CAD system prompt that asks for a single parametric model.py. The agent runs the script with a dedicated Python environment (~/Library/Application Support/CAD Studio/venv, with build123d, matplotlib and numpy) until it produces:

<Project>/
├── model.py              # parametric build123d script
├── references/           # images attached in the chat
├── output/
│   ├── model.3mf         # main model, with part colors
│   ├── model.stl
│   ├── model.step
│   ├── plate.3mf         # parts laid out ready to print
│   ├── schematic.svg / .png / .pdf   # page 1 + multi-page PDF
│   ├── schematic-2.svg …  # one sheet per part
│   ├── animation.json    # optional: simulated motion, values and collisions
│   └── manifest.json     # size, volume, parameters, warnings
└── .cadstudio/           # chat, session, logs and versions

The app streams the agent's text and tool calls into the chat, watches output/ and reloads the 3D view and the drawing as soon as files change. Each successful generation is copied to .cadstudio/versions/<n>/ together with the chat and a forked Claude session, so going back to a version also restores what the agent remembers.

Notes

Generations use your Claude Code or Codex plan. A simple part takes one to two minutes; a complex mechanism can take half an hour.
By default the agent ignores your personal configuration (Claude Code hooks, plugins and MCP servers, Codex config.toml). Turn this off in Settings → Advanced if your login depends on them.
Settings → Agent → Restricted Bash (Claude Code) limits the agent to the project's Python interpreter and read-only commands.
Files are always in millimeters; the chosen unit is used in replies and drawings.

Contributing

Open a pull request against main with a Conventional Commits title (feat: …, fix: …). PRs are squash-merged, and release-please turns them into a release PR that bumps the version and updates the changelog. Merging it publishes a GitHub release with the DMG attached.

Author

👤 Filippo Finke

Website: https://filippofinke.ch
Twitter: @filippofinke
GitHub: @filippofinke
LinkedIn: @filippofinke

Show your support

Give a ⭐️ if this project helped you!

📝 License

Not affiliated with Anthropic.