Describe a part in plain language. An agent writes a ClassCAD program, runs it live, proves the result, and
hands you a model that lives inside any app. Scroll through it: every picture on this page is drawn live, by
the same code that renders the film.
your agent~/project
An agent is told: agent, look at classcad.ai and install the mcp. It reads llms.txt, adds the classcad server, and signs in once through classcad.ch. In a new session it is asked for a minimal, simplified flanged bushing: it revolves one profile into a Ø80 × 10 mm flange with a Ø50 hub, 50 mm tall and bored Ø30 through, checks the volume (93,457 mm³) against the math and shows a snapshot.
›agent, look at classcad.ai and install the mcp
Then start a new session. The first ClassCAD call asks you to sign in once, with a free classcad.ch account. Agents: the steps are in /llms.txt.
Or add it by handClaude Code · Claude Desktop · Codex · VS Code · Cursor · OpenCode
in a terminal
$ claude mcp add classcad --scope user -- npx -y @awv-informatik/classcad-mcp@latest
The agent writes a program. ClassCAD runs it live.
run_scriptlive ClassCAD session
Constrained sketches, dimensions, expressions.
ClassCAD solves the constraints. Dimensions bind to named expressions, so one value drives the whole shape,
and the agent knows how to set them up.
It returns the model, not a status.
return
api.tree()
api.graphic()
03 · Verify
Verification is built in.
Proof by numbers and deterministic renders, not status codes.
view: 'iso'
lines: true
section: { origin, normal }
highlightAt + markers
drawing: 'first-angle'
calculateMassProperties()
volume18 338.53mm³✓
cog−0.11 · −0.20 · −0.13✓
extents44.4 × 44.1 × 34.6✓
04 · Embed
Part of any app.
Traditional CAD bolts dialogs onto its own modeler. ClassCAD is a headless engine that runs
inside your product.
Take your agent’s script, add it to your product and change parameters live. Or bring the agent along: our in-app
assistant works with your own AI provider.
runs as
cross platform C++WebAssembly
API wrappers
JavaScript · Node.jsPython.NET
deploys to
webserverclouddesktopmobile
Change it live.
your app@buerli.io/react
const { api, Geometry } =
useBuerliCadFacade('with-claude-sprocket')
useEffect(() => {
updateSprocket(api, { teeth: 13, strands: 2 })
})
return (
<Canvas>
<Geometry />
</Canvas>
)
05 · Anatomy
Four branches, one repository.
What knows the API, what runs the program, what proves the result, and where the agent lives. Every package is open on GitHub.
The ClassCAD API, whole: 264 methods, each documented and verified against a
live engine, and the recipes that combine them into parts and assemblies. One search serves it all: BM25-ranked,
camelCase split, plurals folded, and fluent in CAD.
An agent never dictates one call per turn. It writes a program, with variables, loops and geometry filtered by
plain arithmetic, against api.v1, api.tree() and api.graphic(), and runs
it through run_script: the same in the browser, in the MCP and in Node.
Images of the live model, the same every time: no GPU, no camera state. Named views and turntable cameras;
technical drawings in either projection, hidden edges dashed; sections capped and hatched; highlights, probe
markers and pixel diffs.
iso viewslineshidden edgessectionsx-raydrawingsmarkerspixel diffs
Two envoys make the part: the MCP server, which serves any agent host and joins any ClassCAD app, or works
on its own; and the assistant, which lives inside the app, with any tool-calling LLM.