Protoloop

README excerpt

# Protoloop

An agentic CAD / 3D-model studio for macOS (Apple Silicon). Describe a part in plain
language — Claude plans it, writes **parametric** CAD source, renders a live 3D model you can
rotate, **measure**, tune with **sliders**, and export. Built for engineers (CNC / CAD / hardware),
the way an agentic coding tool is built for software engineers.

## What it does

- **Four-column workspace** — Creations library · Chat · large 3D preview · Parametric sliders.
- **Chat → model** — Claude authors parametric CAD source + a parameter schema; the app renders it.
  On the first message it asks a few clarifying questions (planning), then builds.
- **Four open-source engines**, all LLM-friendly and agent-controllable:
  - **OpenSCAD** (installed binary) — fast, scripted solids.
  - **JSCAD** (`@jscad/modeling`) — pure JS, runs in-process, zero external deps.
  - **CADQuery** & **build123d** — Python B-rep on OpenCASCADE, export **STEP** for manufacturing.
- **Parametric sliders** re-render with **no LLM call** (the fast-path) — drag a dimension, the mesh
  updates sub-second.
- **Measure tool** — click two points on the surface, get the distance in mm.
- **Rotate around the object's center**, auto-frame, materialize animation, live build progress.
- **Concurrent chats** — every creation keeps generating in the background while you work on others.
- **Two model backends** — the installed **Claude Code CLI** (default; uses your Max login, no API
  key) or the **Anthropic API** (y