Summarize a CAD model: bounding box, volume, surface area, topology counts, per-solid volumes and centers of mass — plus mass when you pass a density (g/cm³). Reads STEP/STP, BREP, IGES/IGS (B-rep, kernel-exact) and STL/3MF (mesh — triangle sums; volume is only reported for watertight meshes, and the summary names which world it measured). Reads the file on this machine; nothing leaves it.

DFM-lite lint for a B-rep model (STEP/BREP/IGES): kernel validity per solid, non-manifold topology, open (no-solid) surface models, tiny edges/faces (sliver artifacts), and pairwise interference + clearance between bodies against clearance_mm. Every finding carries its evidence and threshold so you can disagree with the rule. Wall thickness, draft, threads, and GD&T are NOT checked — absent, not hidden.

EXECUTES a parametric CAD script (build123d or CadQuery Python) in this pack's own venv as a resource-capped subprocess (CPU rlimit + wall timeout, default 75 s), then exports the script's module-level result shape to the requested formats (default step+glb) in out_dir — default derived/ beside the script, and never a directory containing the script itself (charter: source is truth, artifacts are derived). PARAMS (your params dict) is available inside the script. Returns the written files and a build report: volume, area, bbox, center of mass, the script's own prints.

Tessellate a B-rep model (STEP/BREP/IGES) into a mesh file — STL, GLB, GLTF, or 3MF by out_path suffix — at explicit linear (mm) and angular (degrees) tolerances, echoed in the report. Refuses an out_path that collides with the input (charter). Writes only the one output file.

Geometric diff of two B-rep revisions (STEP/BREP/IGES): volume, area, and bbox deltas, plus per-body matching by shape signature — unchanged, moved (with the displacement), added, removed. This is geometry, not a feature tree: a reshaped body reports as removed+added, and the report says so.

Project a B-rep model (STEP/BREP/IGES) to a 2D SVG or DXF (by out_path suffix) from a named view — front, back, top, bottom, left, right, iso. Visible edges on one layer, hidden edges dashed on another. A silhouette for hand-off, NOT a dimensioned drawing. Refuses an out_path that collides with the input (charter).

Generate a STARTER CAD model from a text prompt via Zoo's ML-ephant API (zoo.dev) — files land in out_dir like any derived artifact, with the editable KCL source beside them when returned. Needs ZOO_API_KEY in this server's environment; answers with a named refusal when it is not set. Verify dimensions before use. Reaches the network.

ISO 286 limits and fits, hole-basis subset: hole H5–H11 against shaft letters d e f g h js k m n p s, sizes to 500 mm. Returns deviations (µm), min/max clearance, and the fit kind (clearance/transition/interference). Computed from the standard's deviation formulas — verify critical fits against the ISO 286-2 tables.

Metric coarse-thread fastener numbers for M1.6–M30: pitch, tensile stress area, tap drill, ISO 273 clearance holes (close/medium/coarse), proof stress for the property class, 75% preload, and a T = K·F·d torque first-cut (K default 0.2, dry) — lubrication changes K dramatically.

Beam bending first-cut (Euler–Bernoulli): case one of cantilever_point, cantilever_udl, simply_point_center, simply_udl; section rect {b_mm,h_mm}, round {d_mm}, or tube {d_outer_mm,d_inner_mm}. Point loads in N, distributed in N/mm, E in GPa (default 200, steel). Returns I, max deflection, moment, bending stress, and a safety factor when you pass yield_mpa. No shear deflection, buckling, or stress concentration.

Total mass and 3D center of gravity from a component list — each item {name, mass_g, x_mm, y_mm, z_mm} measured from one datum. Pass envelope {x_min_mm, x_max_mm, y_min_mm, y_max_mm, z_min_mm, z_max_mm} (any subset of axes) to get a CG-within-envelope verdict.