Serpentine3D
Open-source NURBS surface modeller in the Rhino style on the OpenCASCADE kernel, with an AI assistant and MCP integration so agents can drive modelling sessions.
What it does and how it connects
Serpentine3D is an open-source NURBS surface modeller in the Rhino style, built on the OpenCASCADE kernel. It works with exact curves, surfaces, and solids rather than meshes, and reads and writes Rhino .3dm, STEP, DXF, SVG, OBJ, FBX, and STL, with glTF, USD, and 3MF export and E57 point-cloud import. It runs on Linux, Windows, and macOS, free with no account.
A command line speaks Rhino, with loft, sweep2, filletedge, booleanunion, and more than 200 other commands, plus Rhino aliases, object snaps, layers, and a gumball for pushing faces and rounding edges by hand. Drawings come from the model as A4 to A0 sheets with live detail views, hidden-line views, dimensions, hatching, and title blocks, printed to vector PDF.
An assistant can drive the whole application: the user describes a change and the assistant runs the commands, looks at the viewport to check its work, and fixes its own mistakes, all undoable, using Claude, a ChatGPT account, an OpenAI key, or a local open-weight model. Headless work runs through the built-in editor or serp3d-batch, or any MCP client can drive a live session. Checks before building include zebra stripes, curvature, and draft analysis.
What engineers report
Why there no build for aarch64
2026-11-02Read the original
Alternatives
Compare side by side- SolidCraft
SolidCraft is a parametric solid CAD application in Rust, while Serpentine3D is a Rhino-style NURBS surface modeller.
- agentcad
agentcad is a CLI and MCP server over build123d scripts, while Serpentine3D is a full NURBS modeller with an assistant and MCP.
- CAD-MCP
CAD-MCP drives AutoCAD, GstarCAD, and ZWCAD through an MCP server, while Serpentine3D is a standalone NURBS modeller with its own assistant and MCP.
- CADAgent
CADAgent is a Fusion 360 add-in driven by a self-hosted backend, while Serpentine3D is a standalone NURBS modeller with an assistant.
- cad3dify
cad3dify converts 2D CAD images into STEP models with vision-language models, while Serpentine3D is a full NURBS modeller.
Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- In an inch document, sheet lettering still read and was typed in millimetres, so 1/8 inch text had to be entered as 3.175.Error Index
- DXF files from AutoCAD came in without layer colours, lineweights, linetypes or blocks, and a 13 MB file with 21,455 objects held the window for minutes because the session journal wrote each object out as its own temp file.Error Index
Sources
Not verified
- Pricing: none stated on the repo (the application is free with no account, per the README)
- A named individual builder beyond the chisomobanzi repository owner
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.