refactor: add DesignIR distillation pipeline

text-to-cad/skills/cad-router/SKILL.md

@@ -1,15 +1,15 @@
 ---
 name: cad-router
-description: Route natural-language CAD, mechanical-part, assembly, 3D-printing, and robot-description requests across text-to-cad, SimpleCADAPI, and CADAM; create one editable model-spec.json per part; convert supplied STEP/STP files into exact-base JSON-controlled models; and enforce generation, modification, validation, visual repair, and CAD Viewer handoff. Use for new or modified STEP/STP, SCAD, STL, 3MF, DXF, URDF, SRDF, SDF, or G-code work when the agent must choose a backend, preserve editable sources, edit JSON model parameters, or parameterize an imported STEP.
+description: Route natural-language or image-guided CAD generation and modification, plus uploaded STEP/STP reconstruction and modification, across text-to-cad and SimpleCADAPI. Create one executable DesignIR 2.0 model per part, produce STEP geometry without teacher geometry dependencies, and enforce independent validation, visual repair, and CAD Viewer review.
 ---
 
 # CAD Router
 
-Choose a backend before modeling, keep its source as the editable authority, and normalize every result into one handoff contract. Use three projects by role: text-to-cad owns orchestration, general CAD, refinement, validation, repair, and viewing; SimpleCADAPI owns specialized mechanical families; CADAM owns SCAD execution.
+Choose a backend before modeling, keep its source as the editable authority, and normalize every result into one handoff contract. Use two projects by role: text-to-cad owns orchestration, general CAD, refinement, validation, repair, and viewing; SimpleCADAPI owns specialized mechanical families.
 
 ## Required workflow
 
-1. Convert the request into a brief: part type, dimensions, units, manufacturing intent, required outputs, assembly relationships, editability, and validation targets.
+1. Convert the natural-language or image-guided request into a brief: part type, dimensions, units, assembly relationships, editability, and validation targets. The artifact contract is fixed to executable DesignIR 2.0 plus STEP geometry.
    Never treat a teacher STEP or a single-case DesignIR as experience. Batch case
    JSON belongs to the separate CAD Experience plugin. Generation may consume
    only its promoted schema `2.0` generalized library.
@@ -21,63 +21,55 @@ Choose a backend before modeling, keep its source as the editable authority, and
    python3 scripts/route.py "<request>" --explain
    ```
 
-   Add explicit signals when known: `--output step`, `--output stl`, `--manufacturing machining|printing|laser-cutting`, `--edit-source path/to/source`, `--existing-model`, `--assembly`, or `--browser-controls`.
+   Add explicit signals when known: `--edit-source path/to/source`, `--existing-model`, or `--assembly`.
    The router auto-discovers the workspace `cad-experience-library/library.json`,
    infers an experience family and feature roles from the request, and emits a
    backend-neutral `design_plan`. When promoted `reconstruction_grammar`
    records match, instantiate their symbolic parameter roles, datum roles,
    canonical stages, and validation roles in the new part's
-   `model-spec.json`; fill values from explicit user dimensions first and
+   DesignIR; fill values from explicit user dimensions first and
    dimensionless distributions second. Use `--experience-library`,
    `--experience-family`, or repeated `--experience-feature` only to override
    those defaults.
 3. Follow the selected route unless a hard environmental constraint makes it unavailable. If overriding it, record the reason in the task manifest.
 4. Load only the selected backend reference from `references/capabilities.md` and the matching installed Skill:
    - `build123d`: use `$cad`; this is the default for general STEP-first mechanical parts, assemblies, and existing STEP modification.
-   - `simplecadapi`: use an installed SimpleCADAPI Skill/runtime; prefer it for gears, racks, ring gears, bearings, cycloidal parts, reducers, replayable graphs, semantic tags, and FreeCAD interchange.
-   - `cadam`: generate editable `.scad`, then execute `node scripts/cadam_compile.mjs <source.scad> <output.stl|output.dxf>`. Set `CADAM_ROOT` or pass `--cadam-root` when the CADAM checkout is not beside text-to-cad. Prefer it for fast parametric printable models, repeated patterns, decorative CSG, and parameter controls.
+   - `simplecadapi`: use an installed SimpleCADAPI Skill/runtime; prefer it for gears, racks, ring gears, bearings, cycloidal parts, reducers, replayable graphs, and semantic tags.
 5. When the route reports `requirement_refinement` or `visual_repair`, refine the brief, generate, execute, inspect multiple views, and repair no more than three visual mismatch rounds before asking the user.
-6. Generate into a task-owned directory and start CAD Viewer with that task directory as `--dir`; do not expose the repository-wide fixture library for a task review. Write one `model-spec.json` per part and treat it as the editable geometry contract; keep `cad-task.json` as the execution record. Read `references/model-spec.md` before creating, importing, or modifying a model specification. Never change backend during an edit unless conversion is explicitly requested; modify the recorded source of truth.
-   For a supplied STEP/STP without an editable generator, create an
-   `exact_step_base` specification with `scripts/model_spec.py import-step`.
-   Preserve the copied STEP as the immutable exact B-Rep base and express later
-   edits as named JSON parameters and modification features. Do not claim that
-   arbitrary STEP recovers its original sketches, constraints, or feature
-   history.
-   For modification, prefer a native Python/SCAD generator. With STEP only,
-   inspect the explicitly supplied model and perform the smallest local feature
-   rebuild possible. For major topology changes, reconstruct from that model
-   under the promoted experience methods while preserving unchanged interfaces.
+6. Generate into a task-owned directory and start CAD Viewer with that task directory as `--dir`; do not expose the repository-wide fixture library for a task review. Write one `*.designir.json` per part and treat it as the editable geometry contract; keep `cad-task.json` as the execution record. Read `references/designir-2.0.md` before creating, reconstructing, or modifying a model. Never change backend during an edit unless conversion is explicitly requested; modify the recorded DesignIR source of truth.
+   For a supplied STEP/STP, the deterministic ingestion service may extract
+   private teacher evidence. The reconstruction agent receives that evidence,
+   never the STEP itself, and must author complete executable DesignIR. Compile
+   it in an isolated environment where the teacher STEP is absent.
+   The DesignIR and generator must not import STEP, embed B-Rep or meshes, retain
+   face references, or use the source model as a base feature. The acceptance
+   agent alone compares the teacher and reconstructed STEP.
    If the request does not name the source part family, inspect the explicit
    source first and rerun the experience query with `--experience-family` and
    `--experience-feature`; do not guess across family-scoped experience.
-7. Validate against the brief. STEP-first routes must run geometry inspection and snapshot review. Mesh routes must check compilation, bounds, solidity/manifold facts when available, and snapshot review.
+7. Validate against the brief. Run STEP geometry inspection and snapshot review.
    For experience-informed generation, record which generalized methods were
    applied, including the reconstruction grammar ID and instantiated symbolic
    roles. Validate against the user's brief and held-out targets, never against
    parameters exposed from the same source case.
-8. Write a `cad-task.json` manifest using the contract in `references/backend-contract.md`. Hand supported artifacts to `$cad-viewer` and return its live links.
+8. Write a `cad-task.json` manifest using the contract in `references/backend-contract.md`. Hand the STEP artifact to `$cad-viewer` and return its live link.
 
 ## Routing rules
 
-- Prefer an explicit user backend when it can produce the required primary format.
+- Prefer an explicit user backend when it can produce the editable STEP contract.
 - Prefer SimpleCADAPI when a supported standard mechanical factory or replay/semantic requirement materially reduces custom modeling.
 - Prefer build123d for general machined parts such as brackets, connecting rods, housings, shafts, flanges, fixtures, and source-driven assemblies.
-- Prefer CADAM for SCAD-native, fast printable, pattern-heavy, or interactive-parameter models. Do not choose it when editable STEP is mandatory.
-- Route DXF, URDF, SRDF, SDF, G-code, printer, or fabrication handoffs to their focused installed Skills after primary geometry generation.
 - Prefer source quality and future modification over the shortest first generation.
 
 ## V1 boundaries
 
 - Do not promise lossless conversion of feature history between backends.
-- Do not treat STL as an editable CAD source when a parametric source or STEP exists.
 - Do not claim engineering certification, tolerance analysis, FEA, CAM toolpaths, or manufacturability without separate checks.
-- Keep GPL/AGPL backends independently installed and invoked; do not copy their implementation into an MIT-distributed Skill.
 
 ## References
 
 - Read `references/capabilities.md` when comparing or invoking backends.
 - Read `references/backend-contract.md` before writing a task manifest or adding another backend.
-- Read `references/model-spec.md` when generating per-part parameter JSON,
-  converting STEP to a JSON-controlled model, or modifying an existing part.
+- Read `references/designir-2.0.md` when generating, reconstructing, or
+  modifying a per-part executable design.
 - `scripts/capabilities.json` is the machine-readable V1 registry used by `scripts/route.py`.