Mechanical Engineering Copilot
v0.2.0 — eight verified native Onshape templates and a complete tested pilot. See RELEASE-STATUS.json and verification evidence.
The engineer supplies intent and consequential decisions. The agent researches, compares simple options, implements agreed work, checks it, and communicates problems early. Physical fit, strength, load ratings, manufacturing capability and qualification remain separate evidence gates.
Quickstart with your AI host
- Open the complete toolkit folder in your existing AI host. Read
AGENTS.mdand AI-INTEGRATION.md; keep the folder structure intact. - Choose a verified Onshape source below and open its saved version. Use Copy and edit a verified Onshape template to make a recipient-owned copy. Onshape account access is required.
- Tell your agent the intended change and the constraints that matter. Use its native question widget for consequential decisions, then inspect the feature history, edit/restore evidence and actual STEP readback.
- For a new local record, run
python pipeline.py init jobs/my-part. The pipeline manages decisions and artifacts; it does not make CAD calls or replace engineering review.
Workspace prompt: “Read AGENTS.md and skills/engineering-setup/SKILL.md. Set up this toolkit using tools actually available here. Help me copy one verified Onshape template into my account, make one meaningful editable change, restore the original value, and inspect the actual export. Ask about consequential unknowns. Report remaining physical checks.”
Optional Codex plugin
With the current directory set to this toolkit, a supporting Codex CLI can use:
codex plugin marketplace add .
codex plugin add mechanical-engineering-copilot@mechanical-engineering-local
These commands change the recipient's local plugin configuration; this export did not execute them. Workspace mode works without plugin registration. Copying SKILL.md alone is unsupported because skills depend on toolkit resources and scripts.
Verified native Onshape sources
The saved version v0.2.0 - eight native templates is in document 8fa1688376bbc62bbf64930e, version aeee4f102bf452e86523a21b, microversion 1e990ab1fb6b855e50bc8483. It contains eight Part Studios, 107 authored features and 59 named variables. All reported feature states are OK; sketch readbacks report WELL_DEFINED. Every row below links to the source saved version and its curated evidence.
| Template | Features | Driver edit and restore | Evidence |
|---|---|---|---|
| Annular spacer | 5 | outer_d 30→32→30 mm | Saved Part Studio · evidence |
| Two-slot plate | 11 | slot_total_L 12→16→12 mm | Saved Part Studio · evidence |
| Four-hole plate | 10 | plate_L 60→64→60 mm | Saved Part Studio · evidence |
| Five-hole coupon | 14 | pitch 12→13→12 mm | Saved Part Studio · evidence |
| Outer-ring carrier | 21 | boss_H 12→14→12 mm | Saved Part Studio · evidence |
| PCB mount | 16 | post_H 8→10→8 mm | Saved Part Studio · evidence |
| Gusseted bracket | 19 | wall_H 50→55→50 mm | Saved Part Studio · evidence |
| Open tray | 11 | outer_L 80→84→80 mm | Saved Part Studio · evidence |
Each actual STEP passed the frozen independent CSG comparison in both directions and has a canonical FreeCAD 1.1.4 geometry measurement. These checks establish geometry readback for the saved models only.
The recorded Onshape link settings enabled view, copy, link and export. An isolated signed-out browser redirected to Sign in, so an Onshape account is required; anonymous access is not demonstrated. No independent other-person copy test was performed.
Toolkit contents and local tools
| Component | Purpose |
|---|---|
skills/, AGENTS.md, resources/AI-INTEGRATION.md | Intake, agent workflow and AI-host setup |
resources/ENGINEER-WORKFLOW.md, COMPUTER-USE.md | Decisions, bounded work and CAD/browser readback |
examples/onshape-template-specs.json, resources/ONSHAPE-LIBRARY-SPEC.md | Numeric defaults and native evidence links for all eight templates |
examples/native-onshape/, examples/approved-pilot/ | Saved feature responses, edit/restore records, STEP, measurements and independent comparisons |
outputs/free-mechanical-cad/, examples/native/ | Local FreeCAD references and reusable native models |
pipeline.py, scripts/ | Local project records, release consistency audit and helpers |
Run the local plate example with FreeCAD's Python interpreter:
<freecad-python> examples/build_spacer_plate.py --out demo-plate
The local numerical reference is optional. It demonstrates a homogeneous linear-static cantilever, not the eight Onshape parts. Read outputs/free-mechanical-cad/README.md before its large Windows bootstrap. No solver is needed for ordinary dimension edits.
Verification and scope
The final Windows run passed 121 tests and 519 subtests, with 2 Windows symlink-permission skips. Both skills validate, the complete pilot record passes, and the eight-template release evidence audit passes. Exact inputs, commands, exits and logs are in the final software proof.
For optional software tests: python -m pip install -r requirements-dev.txt, then python -m pytest -q -ra. The recorded environment used pytest 9.1.1. For a first CAD session, use the workspace prompt above; installing the optional plugin is not required.
macOS and another person's plugin/copy session were not executed. Geometry checks establish no printed fit, strength, load rating or physical qualification. The engineer reviews consequential design choices and defines the physical checks needed for the intended use.