Cadspec

Cadspec is a CAD as code CLI tool and Rust library for declarative CAD modeling. Write geometry as code in .cf TOML files, watch it live in the browser, and compile to AutoCAD-compatible DXF — built for humans and AI agents working together.

The plan is not drawn — it is declared

Traditional CAD drawings are collections of lines without semantics: impossible to version, diff or automate. Cadspec treats an architectural plan like source code:

Same input → bit-identical output, every time.
git diff works on floor plans.
AI agents can generate and modify designs with surgical precision.

The core loop

cadspec new casa && cd casa
cadspec serve --open        # live preview in the browser

Edit any .cf file — by hand or by asking an AI agent — and the browser updates on every save. Parse errors and constraint violations appear as an overlay instead of a crash. When the design is right, cadspec build emits a deterministic DXF.

Built for agents

Agents get first-class support:

cadspec schema — the full .cf language reference in one command; agents self-discover the format without prior training.
cadspec check --json / cadspec layers --json — machine-readable reports.
cadspec preview — a faithful PNG render plus preview.meta.json with per-entity bounding boxes, so multimodal agents can look at the plan and locate every entity.
cadspec preview --highlight ln-001,tx-002 — labeled markers to visually confirm an edit landed where intended.

How the documentation is organized

Installation — install, update and uninstall.
Quick Start — from zero to DXF.
The .cf Format — layers, primitives, construction tools.
Live Preview — cadspec serve and its controls.
Building & Export — build, watch, DXF import/export.
Working with Agents — the agent-facing toolchain.
CLI Reference — every command and flag.

Part of UniverLab

Cadspec is an experiment of UniverLab, an open computational laboratory. It follows the lab’s engineering principles: one tool one job, reproducibility first, offline-friendly design.