Jarvis Onshape MCP
Claude Code plugin for driving real Onshape CAD with vision-based decomposition and parametric iteration.
What it does and how it connects
Jarvis Onshape MCP is a Claude Code plugin that lets Claude drive real Onshape CAD: sketches, extrudes, fillets, mates, parametric iteration through Variable Studios, and custom FeatureScript features. Every mutating tool returns a structured truth: what changed, what warnings the regenerator raised, and hints for the next move.
Multi-view PNG renders come back as image content so Claude can see the part, and a vision-decomposition skill walks Claude through reading an engineering reference image before building. Drawing OCR runs Tesseract on engineering drawings and returns numeric callouts, and per-feature geometric diffs show bounding box, part count, and mass deltas after each feature.
The README includes a research writeup behind the vision workflow, and the project is versioned at v1.2.0 from April 2026. The repository has no license file: the GitHub API returns no license, so no license is stated.
What engineers report
create_extrude returns HTTP 400: Client error 'Bad Request' on every call, regardless of parameters.
2026-07-30Read the original
Alternatives
Compare side by side- onshape-mcp (gpambrozio)
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Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- Drawing toolset is described as missing basic drafting capabilities and mark-up controls.Error Index
- Large-assembly handling and richer 3D communication workflows are described as limited compared with expectations.Error Index
- Onshape-exported URDF had a camera frame flipped 180 degrees and forearm roll axes 11.0 and 10.7 degrees off; editing the URDF is pointless because the export overwrites it, so a load-time correction table patches the model in memory.Error Index
- Onshape's URDF export puts a roll of -pi on the lidar joint, mirroring every scan, while the link's visual origin carries a compensating +pi so the model looks right in RViz and only the laser scan is wrong.Error Index
- A fillet fails with "both faces next to the edge must be planar" on a part the user built easily in Onshape.Error Index
Sources
Not verified
- Pricing: none stated on the repo.
- Activity: last push 2026-04-22, so the project looks quiet; the open issues report HTTP 400 failures on feature-creating tools against the current Onshape API.
- A named individual builder beyond the repository owner handle ReshefElisha
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.