shapecraft 0.1.2a1

Craft real CAD with Claude. MCP server for Onshape.

shapecraft

Craft real CAD with Claude. Any shape. Any tool.

Status: v0.1.2-alpha — auth + reads working, writes under active repair. Live integration testing against Onshape revealed that the feature-write path silently produced solver errors in v0.1.0 / v0.1.1 (HTTP 200 but featureStatus=ERROR). v0.1.2a1 makes add_feature raise on solver rejection so failures surface immediately. Systematic feature-payload fixes land in v0.1.3. See CHANGELOG.md for the full list of known-broken tools.

shapecraft gives Claude first-class tools to drive professional parametric CAD. The MCP surface covers document/workspace management, sketch primitives + splines + constraints, every core feature (extrude/revolve/loft/fillet/chamfer/pattern/boolean/thicken), offset planes, variable tables, FeatureScript evaluation, exports to STL/STEP/GLTF, and assembly operations with 4 mate types — but most feature-write tools are currently producing solver-rejected payloads and will raise OnshapeError until v0.1.3 lands.

Install

uvx shapecraft   # or: pip install shapecraft

Register with Claude Code

claude mcp add shapecraft \
  -s user \
  -e ONSHAPE_ACCESS_KEY=<your_key> \
  -e ONSHAPE_SECRET_KEY=<your_secret> \
  -- uvx shapecraft

Get your keys at dev-portal.onshape.com.

Tools (MCP surface covers ~48 operations, many currently failing at the solver — see CHANGELOG)

• shapecraft_list_documents
• shapecraft_create_document
• shapecraft_create_part_studio
• shapecraft_sketch_rectangle
• shapecraft_sketch_spline (NEW vs hedless)
• shapecraft_offset_plane (NEW)
• shapecraft_extrude with symmetric + reverse flags (upgraded)
• shapecraft_loft (NEW)

Plus build_coincident_constraint helper (sketch constraint builder — first of 7 coming in T1).

See the design spec for the full T1 → T3 roadmap.

Development

python3 -m venv venv
./venv/bin/pip install -e ".[dev]"
./venv/bin/pytest tests/unit -v

Integration tests (tests/integration/) hit live Onshape and require ONSHAPE_ACCESS_KEY/ONSHAPE_SECRET_KEY env vars.

Releasing

1. Bump version in pyproject.toml
2. Update CHANGELOG.md
3. git tag v0.1.0 && git push --tags
4. release.yml publishes to PyPI via trusted publishing (configure once at pypi.org)

License

MIT. See LICENSE.

Credits

Inspired by hedless/onshape-mcp (MIT per its README) — shapecraft is an independent reimplementation that covers a broader slice of the Onshape REST and FeatureScript API.