Declaring named connection frames with a connectors(p, part) function and positioning assembly instances by mates - rigid, revolute and cylindrical joints, the anchor rule, and the mate forest.
L/U/Z brackets, gussets, bolt patterns, adjustment slots and NEMA motor mounts — sizing, clearances, load path, and the build123d order that survives a rebuild.
Executable design intent - SPECS declarations checked on every rebuild, the part/assembly/FEM tiers, requirement traceability, and the spec-first workflow the checks tool and geometry CI consume.
Two-part boxes, housings and cases - wall thickness per process, shelling, lid lips and grooves, screw bosses, PCB standoffs, vents, draft.
Design rules for FDM/FFF 3D printing — wall and feature minimums, 45 deg overhangs, bridging, teardrop holes, elephant foot, warping, orientation, tolerances.
Running and reading AgentCAD FEM — fem_static, fem_modal, fem_thermal — fixture and load faces, mesh size, safety factors, deflection limits, material_basis, and what not to trust.
Sizing mating features — ISO 286 hole-basis fits (H7 with g6/h6/k6/p6), printed-part clearances, bearing seats, dowel pins and heat-set insert holes.
The hole wizard - clearance, tapped, counterbore, countersink and drilled holes from ISO/ASME tables, the plane predicate, per-instance verification and the machine-readable hole record.