simple-3d-modeling-mcp

An MCP (Model Context Protocol) server that lets anyone create, iterate on, and export 3D models through natural conversation with an LLM. Works with any MCP-compatible client — Claude, ChatGPT, Codex, and more. Zero setup — the OpenSCAD engine is bundled via WebAssembly. No system install needed.

Features

• Zero-setup — npm install simple-3d-modeling-mcp and go. OpenSCAD runs via bundled WASM.
• Inline previews — rendered PNG images appear directly in the chat
• Turntable animations — 360 degree animated previews (APNG) for first-look at new models
• Multi-view grids — front, right, top, and perspective in a single image
• Live browser viewer — interactive 3D viewer with rotate/zoom/pan, auto-updates on each render
• Print-ready exports — STL, 3MF, AMF, and more formats for 3D printing
• Native OpenSCAD support — optionally install OpenSCAD for faster rendering and library support (BOSL2, MCAD)

Quick Start

This server uses the standard Model Context Protocol over stdio, so it works with any MCP-compatible client. Pick yours below:

Claude Desktop

Easiest: Download simple-3d-modeling.mcpb and double-click to install.

Or manually add to your claude_desktop_config.json:

{
  "mcpServers": {
    "simple-3d-modeling": {
      "command": "npx",
      "args": ["-y", "simple-3d-modeling-mcp"]
    }
  }
}

Claude Code

claude mcp add simple-3d-modeling -- npx -y simple-3d-modeling-mcp

ChatGPT Desktop (macOS)

Go to Settings → MCP Servers → Add Server, then enter:

• Name: simple-3d-modeling
• Command: npx -y simple-3d-modeling-mcp

OpenAI Codex CLI

codex mcp add simple-3d-modeling -- npx -y simple-3d-modeling-mcp

Other MCP Clients (Cursor, Windsurf, etc.)

Any client that supports MCP over stdio can use this server. The command to run is:

npx -y simple-3d-modeling-mcp

Consult your client's documentation for how to register an MCP server with that command.

That's it. No OpenSCAD install. No PATH configuration.

Tools

| Tool | Description | |------|-------------| | render | Render code to a PNG preview image (also pushes to live viewer) | | render_turntable | 360 degree turntable animation (APNG) | | render_multiview | Multi-view grid (front, right, top, perspective) | | export | Export to STL, 3MF, AMF, OFF, DXF, SVG | | validate | Syntax-check without full render | | open_viewer | Open interactive 3D viewer in browser | | cheatsheet | OpenSCAD language quick-reference | | list_libraries | Discover installed libraries (native OpenSCAD only) | | get_version | Check engine info (WASM or native) | | read_scad_file | Read an existing .scad file |

Live Browser Viewer

On first render, an interactive 3D viewer automatically opens in your browser:

• Live updates — model refreshes automatically on every render
• Model history — sidebar shows every version, click to revisit
• Dimensions — bounding box and volume computed from geometry
• Export — download STL directly from the viewer
• Controls — rotate (drag), zoom (scroll), pan (right-drag), wireframe, auto-rotate, grid

Compatibility Notes

| Client | Inline Image Previews | Export / Validate / Viewer | |--------|----------------------|---------------------------| | Claude Desktop | Yes | Yes | | Claude Code | Yes | Yes | | ChatGPT Desktop | Yes | Yes | | OpenAI Codex CLI | Depends on terminal | Yes | | Cursor / Windsurf | Yes | Yes |

Tip: Even if a client doesn't render inline images, the live browser viewer (open_viewer) works everywhere — it opens a standalone browser tab with full 3D interaction.

Native OpenSCAD (Optional)

For faster rendering and library support, install OpenSCAD. The server auto-detects it on your PATH and uses it when available.

Environment Variables

| Variable | Description | Default | |----------|-------------|---------| | OPENSCAD_PATH | Explicit path to native OpenSCAD binary | auto-detected | | OPENSCAD_WORK_DIR | Directory for temporary render files | OS temp dir |

Example Conversation

You: Make me a phone stand that holds the phone at 60 degrees

LLM: calls render — Here's a phone stand with a 60 degree viewing angle. The base is 80mm wide with a 3mm lip. The interactive 3D viewer is open in your browser too. Want me to adjust anything?

You: Make it thicker and add a cable slot in the back

LLM: modifies code, calls render — Updated! Wall thickness is now 4mm with a 12mm cable slot. Check the viewer to spin it around.

You: Perfect! Export it for my 3D printer

LLM: calls export(format="3mf") — Exported to ~/Desktop/phone-stand.3mf (42 KB). Ready to slice and print!

Development

npm install
npm run build        # compile TypeScript
npm test             # run tests
npm run dev          # watch mode

License

GPL-2.0 (required by the openscad-wasm dependency)