Agentcad Skill

CAD tool for AI agents. Use when the user asks you to design, model, or build a 3D object. agentcad executes CadQuery Python scripts and produces STEP files,...

Security Scan

The skill manifest is internally consistent with a CLI-based CAD helper: it only requires the agentcad CLI and Python, asks for no credentials, and contains no hidden install or network steps.

Purpose & Capability

The name/description (CAD tool that runs CadQuery scripts) matches the declared requirements: it needs the agentcad CLI and Python 3.10–3.12. No unrelated binaries or credentials are requested.

Instruction Scope

SKILL.md instructs the agent to run the agentcad CLI and to read generated artifacts (preview.png, diff images, STEP/GLB files) — this is expected. One minor scope note: the doc explicitly tells the agent to open the interactive viewer in the user's browser 'every run, unprompted', which is an aggressive UX preference (intrusive if automated). Otherwise the instructions do not reference unrelated files, env vars, or external endpoints.

Install Mechanism

This is an instruction-only skill with no install spec or archived downloads. The README suggests installing the CLI via pip (agentcad on PyPI), which is a standard distribution channel; the skill itself does not install arbitrary code or fetch from unknown URLs.

Credentials

No environment variables, credentials, or config paths are required. The requested artifacts are local outputs produced by the agentcad CLI; nothing indicates credential or secret access.

Persistence & Privilege

always is false and the skill does not request persistent system-wide privileges. It does not attempt to modify other skills or agent configuration. Autonomous invocation is allowed by default (normal), and no additional elevated privileges are declared.

Assessment

This skill manifest appears coherent for a CLI-based CAD helper. Before installing or using it: 1) ensure you install the agentcad CLI from a trusted source (pip on PyPI) and verify the package/source if you require extra assurance; 2) be aware the skill instructs the agent to open the local viewer automatically after every successful run — if you don't want automatic browser openings, disable that behavior or run agent actions manually; 3) check the CLI's own commands (e.g., any 'feedback' or telemetry commands) so you understand what data might be transmitted externally; and 4) run the CLI in an isolated environment (sandbox/container) if you want to limit risk while you evaluate the tool.

agentcad — CAD tool for AI agents

You have access to agentcad, a CLI that turns CadQuery Python scripts into 3D geometry. All output is JSON. Every command returns "command" and "status" keys.

First-time setup

agentcad init --name <project_name>
agentcad --help   # Read this — it is your complete operational briefing

Core workflow

1. Write a script. No imports needed — cq, show_object, and all helpers are pre-injected. show_object(result) is required.

2. Dry-run first to check metrics without consuming a version:

   agentcad run script.py --output test --dry-run
   

   Check volume, dimensions, is_valid in the response.

3. Run for real. Visual feedback is on by default:

   agentcad run script.py --output label
   

   Every successful run produces (paths in the JSON response):

   • preview.png — 4-view composite (front, right, top, iso). Read this to confirm the part looks right before iterating. One image, all 4 angles.
   • diff.side_by_side — side-by-side PNG vs the most recent successful prior version. Read this when iterating to see what your change did.
   • diff.overlay — tinted (green prev, red this) overlay for subtle shifts. Read only if side-by-side didn't resolve the question.
   • viewer.html — interactive 3D viewer for the user (humans only; you can't render HTML). Mention it to the user so they open it.

   Pass --no-preview only for tight parametric sweeps where latency matters.

4. Show the user. After a successful build, open the interactive viewer:

   agentcad view v1_label/viewer.html   # or output.step / output.glb
   

   Users expect to see the result in a browser. Do this every run, unprompted.

5. Inspect if invalid. If is_valid: false or geometry looks wrong:

   agentcad inspect v1_label/output.step
   

6. Iterate. Fix the script, run with a new --output label. Use agentcad diff 1 2 to compare versions.

Script writing rules

• show_object(result) is required — at least one call.
• These are pre-injected (no import needed): cq, show_object, translate, rotate, mirror_fuse, loft_sections, tapered_sweep, naca_wire, bbox_point, place_at, assemble, ellipse_wire, spline_wire, polygon_wire, rounded_rect_wire, elliptical_sweep, involute_gear_profile
• Helpers operate on TopoDS_Shape. Bridge with .val().wrapped:

  part = cq.Workplane('XY').box(10, 20, 5).val().wrapped
  moved = translate(part, 50, 0, 0)
  

• To show helper output:

  show_object(cq.Workplane('XY').newObject([cq.Shape.cast(topo_shape)]))
  

• For OCP internals (gp_Pnt, BRepPrimAPI, etc.), import manually.

Key commands

Command	Purpose
agentcad init --name NAME	Initialize project
agentcad run SCRIPT --output LABEL	Execute script, produce STEP + metrics
agentcad run ... --dry-run	Metrics only, no version consumed
agentcad run ... --no-preview	Suppress preview (on by default)
agentcad run ... --render iso,front	PNG views
agentcad run ... --export stl,glb	Mesh export
agentcad run ... --params k=v,k=v	Override script parameters
agentcad render STEP --view SPEC	Post-hoc renders with camera control
agentcad export STEP --format stl,glb	Post-hoc mesh export
agentcad inspect STEP	Topology report (validity, free edges)
agentcad diff REF1 REF2	Compare versions
agentcad context	Project state
agentcad docs [SECTION]	Deep-dive docs (16 sections)
agentcad view FILE	Run this after every successful build — opens GLB/STEP in the user's browser

Debugging playbook

1. Check metrics first — volume and dimensions catch most issues.
2. Read preview.png — the 4-view composite. Fastest way to spot obvious problems.
3. Read diff.side_by_side if iterating — confirms your change did what you intended.
4. Negative volume? Wire winding is backwards (CW instead of CCW).
5. is_valid: false? Run agentcad inspect — check free_edge_count and shell status.
6. Hollow shape? free_edge_count > 0 means open shell.
7. Complex profiles (gears, splines)? Use subtractive construction — cut from a blank cylinder/box instead of building up. See agentcad docs patterns.

Patterns

• Build at origin, then position: Create geometry at origin, use translate() and rotate() to place it.
• Compound vs Union: makeCompound() for assemblies (parts stay separate), .union() for boolean fuse into one solid.
• Parametric scripts: Top-level variable assignments become overridable via --params. Use this for iteration.
• Named parts: show_object(shape, name="wheel", options={"color": "red"}) for per-part metrics and colored GLB export.