freecad-3dprint
Agent skill for designing 3D-printable parts in FreeCAD with headless builds and a slicer gate.
What it does and how it connects
freecad-3dprint is an agent skill for designing 3D-printable parts in FreeCAD on Windows. The agent writes a parametric Python script, FreeCAD runs it headless, and a set of checks reports whether the part will print. The agent never touches the FreeCAD GUI: it reads a JSON report, looks at rendered views of the part, and can slice the part with the user's own printer profile before it calls the job done.
The agent agrees a spec first, puts every dimension in params.json, and writes one Python function per feature. The checks cover shape validity, wall thickness, overhangs, flat downward faces classified as bridge, cantilever, unsupported or supported, bed contact, build volume fit and clearances. A print gate refuses the part while a warning is untriaged, an output is stale, or no slice or manual preview exists.
It installs as a Claude Code plugin or as a skill folder for OpenCode, Codex and Gemini CLI. FreeCAD 1.0 or later is required, and PrusaSlicer is optional: without a slicer the user reviews the preview and records the check in params.json.
Alternatives
Compare side by side- freecad-mcp (blwfish)
A FreeCAD MCP server for modeling, CAM and diagnostics, rather than an agent skill that designs 3D-printable parts with a print gate.
- freecad-ai
A FreeCAD workbench with a chat interface that builds and edits 3D models from natural language, rather than a skill that runs FreeCAD headless with printability checks.
- lime-slice
A filament slicer and solid modeler in one window with an MCP server, rather than an agent skill for FreeCAD.
- AgentCAD (lizaixi01)
A CAD runtime for AI agents that makes 2D DXF drawings, rather than a skill for 3D-printable FreeCAD parts.
- CADialogue
A conversational assistant that creates and refines parametric FreeCAD models from text, speech and images, rather than a skill for printability-gated FreeCAD parts.
Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- A part could be reported printable without a slicer check, and a latch shelf passed as a bridge when it was really a cantilever.Error Index
- When an agent fans out parallel create calls through the FreeCAD MCP bridge, the shared connection races: the first object is created even though its call reports failure, and the second object is silently never created with the status still showing healthy.Error Index
- A FreeCAD MCP bridge silently ignored parameters the client materialized from JSON-Schema defaults, so box(size=20) produced a default 10mm shape. The agent believes it built the requested geometry while the model is something else entirely.Error Index
- A FreeCAD user reports fillet/bevel as big weaknesses of FreeCAD and shows a fillet that breaks in FreeCAD and in the FreeCAD-Nxt add-on meant to fix it.Error Index
Sources
Not verified
- Pricing (no price stated on the repository README)
- Real user voices (recent repo activity is the maintainer's own pull requests)
- A named individual builder beyond the repository owner handle nicholaslimck
- A public release (no releases are published)
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.