OpenSCAD with AI assistants (MCP)

Open the editor

Language models are good at writing OpenSCAD: it is plain code, and a part can be described in words. What they lack on their own is a way to run the code, look at the result and measure it. openscad-web fills that gap. The site is a remote Model Context Protocol (MCP) server, so an assistant can compile your design with the real OpenSCAD 2025.03.25 engine, read back exact measurements, look at rendered views, and save the code to your account, while your browser shows every step live.

Connect in two minutes

The server URL is:

https://openscad.bongkow.com/mcp

Claude app (web, desktop, mobile)

1. Settings → Connectors → Add custom connector.
2. Paste the URL and press Connect.
3. A browser tab opens: sign in with Google and press Allow.

ChatGPT

1. Settings → Connectors → Advanced → enable Developer mode.
2. Create a connector with the URL and OAuth authentication.
3. Sign in with Google when asked, then Connect.

Claude Code

claude mcp add --transport http openscad-web https://openscad.bongkow.com/mcp

Then run /mcp, choose openscad-web and Authenticate. The same instructions, with a copy button for the URL, are in the editor's Agent panel.

How sign-in works

openscad-web is its own OAuth 2.1 authorization server. Your assistant registers itself as a client, sends you to a consent page, and after you sign in with Google and press Allow it receives a bearer token. That token is an agent key for your account only. Keys are stored as hashes on the server, every connection is listed in the Agent panel, and Disconnect revokes a key at once. You never paste passwords or API keys into a chat.

What the assistant can do

• Find and switch designs: list_designs, open_design, new_design, fork_design (try a variant without touching the original), search and fetch.
• Read and write code: get_code, set_code, and get_project for the design's notes, unit, available libraries, OpenSCAD version and 3D-printing rules.
• Check its work: check_model compiles the complete code, saves it, and returns size, volume and whether the mesh is manifold, plus iso, front and top renders.
• Tune parameters: get_params and set_params change Customizer values without editing the code.
• Use your references: get_reference_images reads up to four photos or sketches you attached to the design.
• Hand over files: export_model returns a download link for STL, 3MF or OFF.
• Leave notes: add_note records what a design is for and which values were assumed, for the next session.

The interactive view inside the chat

In chats that support MCP Apps, ask “Show my current design in the interactive OpenSCAD app.” The openscad_view tool opens a panel with orbit and zoom, standard views, dimensions, source editing, Customizer controls and fullscreen. Compile & save writes to the design you are viewing and updates the website; a stale panel cannot overwrite a newer version. Downloads use private 15-minute links, and Open in Bambu Studio works from the panel too.

Prompts to try

• “Design a phone stand for a 75 mm wide phone at 60°, with a cable slot.”
• “Make the wall thickness a Customizer parameter and check the part is manifold.”
• “Add four M3 mounting holes to my current design and export it as STL.”

Keep the editor open in a browser tab while you chat: each save is pushed to the page, so you can stop the assistant, adjust a value by hand, or take over the code at any point. New to the editor? Read OpenSCAD online — no install, or the STL export guide.

FAQ

Open the editor