Use this when you need to export geometry to a file. One exporter, selected by `target`:
- target:'model' — export the script geometry to one file. Pass { file | code }, a required { output_path }, and { format }. Supported formats: stl (binary STL mesh), step (BREP CAD interchange), dxf (2D cut file for laser / waterjet / CNC: a flat part — plate, panel, extruded profile, in any orientation — exports its outline and holes in its own plane with exact arcs and circles; a sheet-metal part or a returned Region exports its flat pattern; a flat or sheet-metal part also returns sheet { thickness_mm, bend_count }, which a shop needs and the DXF does not carry; options.section { axis: "x"|"y"|"z", at } exports the cross-section of any part in world coordinates (plans, profiles); a multi-part model (cut list) writes all parts side by side on output_path, one layer per part, plus parts/<part>.dxf per part (reported in part_files; options.layout 'sheet' writes the combined sheet only); any other part fails with export.dxf.non-planar), 3mf (slicer-friendly mesh: one named object per part, colours as core-spec basematerials named by the part's engineering material; options.arrange 'plate' packs parts on the bed at Z=0 without overlap (options.orient puts each part's largest flat face down), 'assembled' keeps them together as one multi-part object for multi-colour prints; options.slicer 'bambu' | 'orca' | 'prusa' adds that slicer's per-object name + filament-slot sidecar — slot N is the Nth distinct colour/material), options.infill { fromFea: '<study>' | true, bands?, pattern? } = stress-graded FDM infill (requires the local CalculiX + gmsh toolchain; without it the export fails with fea.solver.unavailable): solves the feaStudy and writes modifier volumes, each with its own infill density (Orca/Bambu format by default; options.slicer 'prusa' writes PrusaSlicer's format instead, since the two are not interchangeable); the result carries infill { bands, saving, images }), gcode (installed OrcaSlicer output; preserves G-code and returns optional gcode_stats with header generator identity and slicer-predicted time/material), glb (web-viewer / AR with PBR materials), obj (Wavefront indexed triangle mesh), usd (ASCII USDA triangle mesh in millimeter, Z-up coordinates; multi-part scenes emit one named mesh per part), svg-drawing (third-angle engineering-drawing sheet: front/top/left + isometric views, hidden edges dashed, tangent edges thin, overall bounding-box dimensions, title block; assemblies are drawn with inter-part occlusion; pass options.annotations to dimension specific features instead of the bounding box; pass options.exploded { factor, mode } to explode the isometric cell, options.balloons to number parts from the BOM, and options.partsList for an item/name/qty/material table above the title block). overall bounding-box dimensions, title block; assemblies are drawn with inter-part occlusion; pass options.annotations to dimension specific features instead of the bounding box, options.autoAnnotate to derive datums A/B/C, grouped hole callouts with position tolerances, hole positions, overall size, radius and chamfer callouts, flatness and an ISO 2768 note from the geometry (the result carries drawing_report with placed / overlapped counts), and options.sections for real section views on any cutting plane). pdf-drawing (the same sheet — views, dashed hidden lines, dimensions, hole callouts, GD&T, sections, parts list — as a printable vector PDF on a standard sheet, one call: ISO a4|a3|a2|a1|a0 or ANSI ansi-a…ansi-e landscape, default a3, or sheet "auto" / "auto-ansi" for the smallest sheet that holds the views at 1:1; the drawing scale is picked to fit; projection "third" (default) or "first" arranges the views and draws the matching symbol; a full title block carries title, part name, material, scale, units, sheet size, date and revision, settable through options.title / partName / material / revision / date; autoAnnotate is on unless options.annotations is given). Robot descriptions: urdf (tree-topology robot description), srdf (motion-planning semantics layered over the URDF), sdf-gazebo (SDFormat 1.10 with native ball joints, closed loops, and solved per-link poses), usd-isaac (ASCII USD physics stage: PhysicsArticulationRootAPI root, one rigid body per link at its solved pose with mass / centre of mass / principal inertia, PhysicsFixedJoint/PhysicsRevoluteJoint/PhysicsPrismaticJoint per mate with token axis, two-sided joint frames and limits, UsdPreviewSurface materials from the part appearance, and joint drives only when declared in options.drives { <mate>: { stiffness, damping, maxForce?, targetPosition? } }; options.collisionApproximation is convexHull | convexDecomposition; planar/cylindrical/pin_slot/ball mates fail closed with export.usd.joint-unsupported). bom-csv / bom-json (bill of materials over assembly.model()/solvedModel(): one row per distinct part — grouped by geometry/catalog identity, not name — with real instance quantity, kind, material, density, mass, bbox, fabrication process (`process` + `processSource`), and catalog provenance for purchased parts; same numbers as inspect({ of: 'bom' })). order-pack (a zip: one single-body file per fabricated part — STEP always, plus STL for 3d-print and DXF for sheet-cut rows, per-part drawing PDFs where available — with bom.csv/bom.json, vendor paste handoff texts for purchased rows and a machine-readable manifest; options processes / items narrow which rows are packed; nothing is uploaded). bend-table (tube bender tables over tube() records: one <tube name>.csv per tube with the LRA bend table, XYZ points, cut length and last straight; output_path is a DIRECTORY and the written files are reported in table_files; a script with no tube() fails with export.bend-table.no-tubes, and a script whose tube gates report errors writes nothing). urdf and sdf-gazebo also write one meshes/<part>.stl per link, and usd-isaac one meshes/<part>.usda mesh layer per link, next to output_path (reported in mesh_files) — ship the whole directory to the consumer. STL exports run a watertight verify by default; failures return ok: false with export.mesh.not-watertight (open-edge count + up to 5 crack-cluster locations) but the file is still written so the broken mesh can be inspected. STEP exports check B-rep validity and mesh watertightness by default; failures return ok: false with export.brep.invalid or export.mesh.not-watertight, while keeping the STEP file for inspection. Set options.verify: false or pass { no_verify: true } to skip STEP checks. Optional { feature_id } selects which feature to export (default: last). Optional { options } carries per-format options bag (see the kernelcad-mcp skill for the per-format keys: step unit/verify, dxf layers/tolerance/unit/section/layout, 3mf printUnit/embedSource/arrange/orient/slicer/printer/infill, glb axis/draco).
- target:'part' — export solved-assembly parts as individual binary STL files in their modeled (world-frame) positions. Pass { file | code }, plus { part, output_path } for one part or { output_dir } for all parts (files land at <output_dir>/<part>.stl). A watertight verify runs on every exported mesh by default and fails the call with export.mesh.not-watertight; unknown part names fail with export.part.not-found listing the valid names.
Pass { no_verify: true } to skip the watertight gate. All params except `target` are forwarded verbatim; each target fails closed on its own missing required params.
Hosted server: the file is written on the kernelCAD server, NOT on the caller's machine. The result carries `downloads[]` — an HTTPS `url` per file (expires after 24 h; give it to the user) — Small text files an agent can read (SVG, DXF, URDF, JSON, CSV; up to 32 KB) also come inline as an embedded resource; STEP, STL, 3MF and GLB are link-only — do not fetch them into your context, give the user the link. `output_path` only names the file; the returned `output_path` is a server-side path, usable only as `file` in later calls to this server. HEAVY FORMATS (step/stl/3mf/glb): if OCCT serialization outlives the client tool-call limit, this tool returns { ok:true, status:"running", code:"export.deferred", job_id } while the export continues on the server — poll by calling export({ job_id }) until status is done/failed. CRITICAL: open_in_studio / paint does NOT need STEP. On export.deferred or any STEP stall, call open_in_studio immediately for the shaded widget; do not block paint on export.