Checking

Independent intent

Requirements describe the user’s needs independently of the model and its selectors. vxl check admits syntax and types; only a build obtains geometric evidence. If exact-solid admission fails, inspect summary structural_gate and warnings; solid_count is not_measured with structural_gate_failed even when the raw count matches its nominal.

Requirements

Requirement cookbook

Each exact feature requirement locates one feature. For delivered mesh kinds use the mesh card. A planar_face / std.datum_plane is a plane: several coplanar faces (feet, a mirrored or patterned part, a face split by a groove) are measured as one. normal is outward from the material; on a pocket or groove face it points into the void (groove floor: +z). A build row opposite_normal_at_station means: reverse normal. There is no expect field (VXL-R601). Use near or requirement at_each to disambiguate. Defaults materialize at check time.

Feature → statement → the requirement that catches it being wrong. "Catches" means a build with that mistake does not RELEASE. Every exact part also takes solid_count and closed_delivered_mesh; mesh topology uses component_count instead of solid_count.

Measurement card: outer_diameter needs diameter, principal axis, axis_at and span:{from,to} equal to one maximal full-turn band of the observed outward cylinder wall (within boundary tolerance), not an arbitrary sub-interval of a band. A band is a connected station interval where the validated chart cells cover the whole turn exactly once; it ends at a full circular ring or at a retained boundary station where coverage becomes partial. A plain complete wall has one band equal to its full axial extent. With several bands, the authored span selects the matching band; if none matches, the row is a measured Fail and reports every observed band. A later Boolean may therefore leave a measurable intact band even when it notches another part of the same wall. The candidate's existing wall_incomplete classification is retained; nonempty bands make only the matching OD span measurable. Unsupported non-line trims remain wall_trim_unsupported. The completeness rule for hole is unchanged. For a grip at z=20 with length 56 ending at the guard's bottom face z=76, write the whole maximal band:

{"id":"r_grip_od","kind":"outer_diameter","subject":"dagger","diameter":24,
 "axis":"z","axis_at":[0,0,0],"span":{"from":20,"to":76}}

sharp_boundary and finishing_run need independent between:{first:{planar:{normal,at|through}},second:{planar:{normal,at|through}}} and run:{axis,from,to} with increasing endpoints; no names or nested near. A finishing run adds exactly one finish:{fillet:{radius,tol?}} or finish:{chamfer:{distance,tol?}}. Every relevant segment must qualify, and interior gaps fail; local size rows do not prove full coverage. A blind slot uses blind:{mouth,floor} instead of through; its complete planar stadium floor and empty observed prism are measured. Slot/OD boundary defaults to position; slot boundary is positive, below width/2 and half blind depth (R689). Equal blind mouth/floor stations first report R611 at blind; change one station to the intended open end or floor, since no positive tolerance can create depth. Position may be zero with explicit positive boundary. A complete connected split bore is one measured group with every sorted member face; disconnected walls remain separate and unsupported trims cannot pass. Write mouths:[{at:<declared open station>,style:"sharp"}] for an explicit sharp opening; omit it only when no absence-of-modification claim is intended. Complete Sharp chains pass, proved modifications fail, and Unknown/incomplete chains stay not measured. See the tested mouth and split recipes. Sharp-mouth/split-bore corpus: 18 fixtures, six RELEASE and twelve designated-row HOLD in the recorded native measurements.

A sharp-run gap with proved detail.modified_intervals requires removing the chamfer, fillet or break-producing cut in parts[].steps to restore the raw crease over run.from..run.to. A finishing-run gap instead requires finishing the missing segment with the authored finish. Correct between or run only if they misstate the intended geometry. For ambiguous cylinder groups, narrow positive locate around axis_at only when axes differ; coaxial groups instead need the intended diameter and span or through/blind extent to distinguish them, or removal of unintended competing geometry. For per-probe resource limits, simplify topology in parts[].steps on subject; removing redundant requirements alone cannot repair that scan.

Full rules: VXL §7 (statements) and §10.1 (requirement kinds).

Locate a requirement by geometry written from the document's params (normal with at/through), not by a construction face name: a requirement that names the faces its own step's selector used follows the same wrong build (VXL-W980).

minimum_wall.min is a lower threshold; the decision depth is min - tol with 0 <= tol < min. disk.margin must be positive and is additional clearance from the disk perimeter to every boundary of its selected face, not a thickness tolerance.

hole.blind names its open end and floor as {"mouth":<len>,"floor":<len>}. A slot names 3D end-centre points with from and to, a width, an axis, and exactly one through:[from,to] or blind:{mouth,floor}. Endpoint components along axis are ignored. The retired positional hole extent is an error (VXL-R674).

Reserved gap kind (reported unsupported, HOLD when required): global_wall. opening has a closed mesh-only payload (mesh card); it is refused on an exact subject. Kinds that used to be reserved are now measurable: thread, helix, gear_teeth, gear_mesh, slot, counterbore, blind_hole, fillet_radius_general, contact_clearance, chamfer_size, feature_distance and text. The spellings counterbored_hole, countersunk_hole, fillet, contact and chamfer are refused as removed aliases (for countersunk_hole write kind: "hole" with a countersink style; countersink.at is allowed only on a through hole). thread, helix and material_region are measurable kinds, not reserved. For material_region, author a cylinder {origin,axis,radius,length} or a right-handed box {origin,x,y,z,size}, expected state:"material" or "void", and positive boundary_clearance. Complete planar/cylindrical boundary exclusion and an actual interior classifier are required; unsupported carriers, incomplete proof and exhausted fixed proof budgets keep required rows at HOLD. A wrong interior state after complete exclusion or a certified boundary witness FAILs. Any other kind is VXL-R602.

Keep-out recipes

A keep-out is a part with role:"keep_out". It is verified, never delivered; acceptance is forbidden. Author it in the same frame as the request, then write a clearance requirement against the deliverable.

Stand-off rule. Touching counts as a collision. Start every keep-out more than clearance.min away from the seat face, or, when the two are meant to touch there, declare that plane in the clearance's contacts and keep min positive. VXL-W930 fires for any clearance whose operands meet on an undeclared plane, or whose declared contact the predicted boxes do not meet (static, predicted boxes only; silence is not measured proof).

Evidence grades

Exact

Exact evidence proves only the measured claim on its named subject. A static check is not a measurement.

ConservativeBound

Under mesh_conservative_v1, Exact PASS or a safe-side ConservativeBound may pass. Keep each measurement’s admission and locator limits from the mesh card.

Estimate and diagnostic-only

An Estimate never satisfies a required check. Compact replies, entity filters and diagnostic previews never decide RELEASE. Required Unknown, incomplete admission and exhausted budgets hold.

HOLD and repair

Read report/summary.json and report/revision-packet.json; fix one typed problem and rebuild within the gated loop budgets. Unresolved problems mean HOLD. Use vextor vxl explain FILE --target ID for source expression dependencies; repair X101 using its bounded candidates (compact replies show the first candidates), and use Q501 did_you_mean only as spelling help.

Traps

Each line is a trap with the code it raises. vextor vxl explain CODE prints the full rule.

Final-file checks

Output contract

• Exactly one authored source file: <name>.vxl.json, schema: "vextor.vxl.v1", units mm and degrees. Native delivery files (such as STEP, STL or 3MF) are separate outputs produced by a build.
• Prefer composition: define a reusable shape in defs[] and use it, use at_each for statements and each for array entries, and use the sealed std library (declare "std": "vxl-std-2") for screw holes, tool access and datums. A use expands in place at check/build time; the expanded form is what runs, and no private __ id is ever writable.
• Write the compact form: omit title, notes and every field that equals its default; use typed functions for repeated formulas, variants[] for named finite override sets, and define a defs[] fragment when the same group of statements would otherwise appear three or more times.
• A missing fact is blocking when different answers give geometrically different parts or it is an interface dimension of something the user owns. Ask via questions[]; check never blocks on it.
• If you reuse a standard dimension, declare the source in assumptions[]; a length param whose id starts with head_, nut_, washer_, screw_, bolt_, thread_ or insert_ and is not sourced is VXL-W960 — take it from a std_ table, record it, or rename it.
• Run vxl check until clean before uploading. Never present a document you have not checked.

Executable facts

The stdlib test instructions cover check versus measure, a missed hole, selector cardinality, Estimate/HOLD and compact HOLD. The 20-document manifest uses existing handwritten examples; check success makes no new build verdict claim.

Delivery decision

Every required need must have acceptable measured evidence. Read the actual label and cell; macOS arm64 development builds remain HOLD. Deliver HOLD files with that label and unresolved questions visible; only an obtained RELEASE may be called RELEASE.

Conventions card

Paste-ready prompt card: CONVENTIONS.md. std library: STD.md; the reference states each rule once.

Examples

• req_chamfer_size
• req_fillet_general
• req_sharp_boundary