🛠️ Claude CAD

An all-in-one CAD · 3D · 2D toolkit for Claude

Give Claude the power to design parametric parts, draft technical drawings, generate DXFs, and prep meshes for 3D printing — producing real STEP · STL · 3MF · DXF · SVG files.

Works on Claude Code, Claude Desktop, and Cowork / claude.ai.

parametric CAD · 2D drafting · DXF · mesh & 3D-print prep · OpenSCAD · + optional Blender / FreeCAD / Rhino

---

✨ What you get

	Capability	Powered by
🧩	Parametric solid modeling → STEP / STL / 3MF / GLB, with measure + render feedback	build123d (OpenCASCADE)
📐	2D technical drawings — framed sheet, title block, layers, real dimensions → SVG / PNG / PDF	svgwrite
✂️	DXF authoring & inspection for laser / CNC / AutoCAD interchange (no AutoCAD needed)	ezdxf
🧱	Mesh repair & printability — watertight checks, wall thickness, slice previews	trimesh
🔩	Script CAD — compile, render, export OpenSCAD models	OpenSCAD
🧭	Smart router that picks the right tool and degrades gracefully per platform	cad-orchestrator
⚡	Optional power tools — Blender, FreeCAD, Rhino/Grasshopper, 3ds Max, Unity, and cloud generators (Zoo, Meshy, Hyper3D)	wired in on demand

Everything ships as one installable plugin plus a Claude Desktop bundle and uploadable skills.

---

🚀 Install

Replace fed3c3sa/claude-cad below with the repository you host this in.

▶️ Claude Code (CLI) — full experience

# 1. Add the marketplace (from GitHub…)
/plugin marketplace add fed3c3sa/claude-cad
#    …or from a local clone:
/plugin marketplace add /path/to/claude-cad

# 2. Install the plugin
/plugin install claude-cad@claude-cad

That's it. You immediately get 6 skills, 5 commands, 3 subagents, and the headless build123d CAD engine (it auto-starts; the first run fetches the CAD kernel once).

Then try:

/claude-cad:model3d a 60×40×10 mm mounting plate with four M4 holes 8 mm in from each corner

💻 Claude Desktop

Desktop installs in two pieces — see plugins/claude-cad/desktop/README-desktop.md for the full walkthrough:

1. CAD engine — add the build123d MCP server to claude_desktop_config.json (use the absolute uv path), or build a one-click .mcpb bundle.
2. Skills — run bash plugins/claude-cad/scripts/make-cowork-zips.sh and upload the .zips under Settings → Customize → Skills.

🌐 Cowork / claude.ai (web)

Web sessions can't run local servers, so you use the pure-code skills (which is most of the toolkit):

bash plugins/claude-cad/scripts/make-cowork-zips.sh   # → dist/cowork/*.zip

Upload each .zip under Settings → Customize → Skills (requires Code Execution + a paid plan). The skills run in the sandbox and return real STEP / STL / DXF / SVG files.

---

🗺️ Platform matrix

Feature	Claude Code	Claude Desktop	Cowork / Web
6 CAD skills (pure code → STEP/STL/DXF/SVG)	✅	✅¹	✅¹
build123d core engine (live build/measure/render loop)	✅	✅	❌²
Slash commands & subagents	✅	➖³	➖³
Optional Blender / FreeCAD / Rhino / 3ds Max / Unity	✅	✅	❌²
Cloud generators (Zoo / Meshy / Hyper3D)	✅	✅	◐⁴

_{¹ via Skills upload (Code Execution + paid plan) · ² local MCP servers can't run on the web · ³ no command/agent system off Claude Code — just ask in natural language and the skills auto-trigger · ⁴ only if exposed as a remote HTTPS connector.}

---

🧠 How it works — a three-layer design

┌──────────────────────────────────────────────────────────────────────┐
│  Layer A — SKILLS  (pure Python, run EVERYWHERE incl. the web)        │
│  code-cad · openscad-cad · svg-2d-drafting · dxf-cad · mesh-3dprint   │
│  · cad-orchestrator                                                    │
├──────────────────────────────────────────────────────────────────────┤
│  Layer B — CORE MCP  (headless, Code + Desktop)                       │
│  build123d-mcp — iterative build → measure → render → export loop     │
├──────────────────────────────────────────────────────────────────────┤
│  Layer C — POWER MCPs  (opt-in, local app or API key, Code + Desktop) │
│  Blender · FreeCAD · Rhino/Grasshopper · 3ds Max · Unity              │
│  · Zoo · Meshy · Hyper3D Rodin                                         │
└──────────────────────────────────────────────────────────────────────┘

The key idea: the everywhere-layer is pure code, so the toolkit works even on Cowork where no server can run. The MCP servers are a power layer for local users — never required.

---

🧰 Commands & skills

Slash commands (Claude Code)

Command	What it does
/claude-cad:cad-setup	Check the toolchain; optionally wire in Blender/FreeCAD/Rhino/etc. and cloud API keys
/claude-cad:model3d <desc>	Design a parametric 3D part → STEP + STL
/claude-cad:draft2d <desc>	Dimensioned 2D technical drawing → SVG/PNG/PDF
/claude-cad:dxf <create/inspect>	Generate or inspect a DXF for laser/CNC
/claude-cad:printprep <file>	Repair + printability report + clean STL/3MF

Or just describe what you want — the skills are model-invoked and trigger automatically.

Skills (all surfaces)

Skill	Scripts	Output
code-cad	build · export · measure · snapshot	STEP · STL · 3MF · GLB · PNG
openscad-cad	validate · render · export	STL · 3MF · OFF · CSG · DXF · SVG · PNG
svg-2d-drafting	draft · dimension	SVG · PNG · PDF
dxf-cad	dxf_write · dxf_read	DXF · preview PNG
mesh-3dprint	analyze · repair · slice_preview	STL · 3MF · OBJ · GLB · SVG · PNG
cad-orchestrator	detect_env · route	routing/JSON

Subagents

cad-modeler (authors geometry, Opus) · cad-reviewer (independent verification pass) · print-prep (3D-print readiness).

---

⚡ Optional power tools

Run /claude-cad:cad-setup blender (or freecad, rhino, zoo, …). The catalog lives in plugins/claude-cad/mcp/optional-servers.json.

Tool	Use it for	Needs
Blender	organic/artistic 3D, render, asset libraries, Hyper3D	local Blender + add-on
FreeCAD	true feature-tree parametric CAD + FEM	local FreeCAD + add-on
Rhino / Grasshopper	NURBS + algorithmic design	Rhino 8 license
3ds Max / Unity	VFX & game pipelines	the app + bridge
Zoo / Meshy / Hyper3D	text/image → 3D, cloud B-Rep	API key

🔒 Security: Blender/FreeCAD/Rhino servers execute code inside the host app with no sandbox. They are opt-in only and never auto-enabled. The core build123d engine runs generated code in a restricted sandbox (AST checks + restricted builtins + timeout). Only enable code-executing servers in trusted, local sessions.

---

✅ Requirements

• uv — the only hard dependency (brew install uv or curl -LsSf https://astral.sh/uv/install.sh | sh). It auto-manages Python and the CAD libraries.
• Python 3.12 for the build123d engine. ⚠️ python3 often defaults to 3.13, which has no OpenCASCADE wheels — the plugin pins --python 3.12 everywhere, and uv will fetch a managed 3.12 if you don't have one.
• OpenSCAD (optional) only for the openscad-cad skill: brew install --cask openscad.
• A paid plan with Code Execution to upload Skills on Desktop / Cowork.

---

🩺 Troubleshooting

Symptom	Fix
build123d import / OCP wheel error	You're on Python 3.13. Always run with --python 3.12 (the plugin does this for you).
Engine won't start on Desktop	Use the absolute uv path in claude_desktop_config.json (which uv), then restart Desktop.
build123d MCP tools missing when testing with --plugin-dir	--plugin-dir does not load plugin MCP servers. Use claude plugin install to exercise the engine.
/plugin update does nothing after changes	Bump version in plugin.json (or omit it to track every commit).
OpenSCAD skill says "not found"	Install OpenSCAD, or use the code-cad skill instead.

---

🙏 Built on great open source

build123d · build123d-mcp · ezdxf · trimesh · OpenSCAD · svgwrite · and the optional blender-mcp, freecad-mcp, rhinomcp. Thank you to all maintainers. 💙

📄 License

MIT © 2026 Federico Cesarini. See LICENSE.