{
  "schema_version": "2.0",
  "routing_policy": {
    "default_backend": null,
    "selection_basis": [
      "native source continuity",
      "standard factory coverage",
      "semantic and replay requirements",
      "geometry vocabulary coverage",
      "assembly requirements",
      "validation requirements"
    ],
    "uploaded_step_execution_engine": "surfaceir",
    "uploaded_step_validation_engines": [
      "surfaceir_geometry_acceptance",
      "simplecadapi_brep_compare"
    ]
  },
  "backends": {
    "build123d": {
      "project": "text-to-cad",
      "runner_skill": "cad",
      "source_formats": ["py"],
      "primary_formats": ["step", "stp"],
      "strengths": [
        "general mechanical parts",
        "machined features",
        "source-level assemblies",
        "freeform profiles, lofts, sweeps, and mixed surface workflows",
        "geometry measurement and validation"
      ],
      "preferred_when": [
        "the part is a custom bracket, housing, shaft, flange, fixture, or enclosure",
        "source-level assembly mates or existing build123d Python must be preserved",
        "the geometry needs custom profiles or surface-heavy construction not covered by a SimpleCADAPI factory"
      ],
      "weak_when": [
        "a deterministic SimpleCADAPI standard factory covers the requested part",
        "operation-graph replay, typed semantic tags, units, or tolerance chains are primary requirements"
      ],
      "source_of_truth": "build123d Python generator"
    },
    "simplecadapi": {
      "project": "SimpleCADAPI",
      "runner_skill": "simplecadapi",
      "minimum_version": "2.0.2",
      "source_formats": ["py", "json"],
      "primary_formats": ["step", "stp"],
      "strengths": [
        "gears, ring gears, racks, bevel gears, and cycloidal discs",
        "bearings, bolts, nuts, roller-chain sprockets, reducers, and joint actuators",
        "replayable ModelResult operation graphs and scene packages",
        "typed semantic tags, topology lineage, and source mapping",
        "physical units and tolerance-chain validation",
        "STEP B-Rep inspection, strict comparison, and slice diagnostics",
        "FreeCAD, Fusion 360, and SolidWorks translation"
      ],
      "preferred_when": [
        "a standard mechanical factory directly covers the requested family",
        "replayable model JSON, semantic edit anchors, units, tolerances, or CAD translation are required",
        "a reusable mechanical product family should become a deterministic library function"
      ],
      "weak_when": [
        "the request depends on complex freeform surfaces outside the supported operation vocabulary",
        "an existing build123d generator or source-level build123d assembly must be preserved"
      ],
      "source_of_truth": "SimpleCADAPI Python generator and model JSON"
    }
  }
}