CAD generation, inspection, and validation

Purpose

Create or modify parametric CAD models from natural-language requirements, generate validated STEP/STP artifacts, inspect geometry references, and return checked outputs. Treat STEP as the primary CAD artifact. Treat DXF, STL, 3MF, and native GLB as secondary workflows that branch from, or accompany, a STEP-first process. For assemblies, prefer source-level build123d joints and named mating datums when the parts have functional assembly relationships.

Use this skill when

Use this skill when the user asks for CAD files, STEP/STP files, build123d source, @cad[...] references, mechanical parts, assemblies, enclosures, brackets, fixtures, holes, counterbores, countersinks, slots, pockets, bosses, standoffs, ribs, fillets, chamfers, shells, source-level joints, mating, or measurements.

Also use it when the user asks for DXF, STL, 3MF, or native GLB output from CAD geometry. Keep those workflows secondary and load dxf.md or supported-exports.md for details.

Do not use this skill for render-only concept art, CAM toolpaths, engineering certification, FEA conclusions, architectural BIM, or freehand illustration unless the user also needs CAD geometry.

Default assumptions

Use these defaults unless the user specifies otherwise:

• Units: millimeters.