{
  "schema_version": "2.0",
  "designir_kind": "executable_parametric_design",
  "model_id": "raised_hub_flange",
  "family": "raised_hub_flange",
  "units": "mm",
  "backend_hint": "build123d",
  "reconstruction_status": "ready",
  "missing_capabilities": [],
  "coordinate_system": {
    "origin": [0, 0, 0],
    "x_axis": [1, 0, 0],
    "y_axis": [0, 1, 0],
    "z_axis": [0, 0, 1]
  },
  "datums": {
    "part_center": {"kind": "point", "at": [0, 0, 0]},
    "primary_axis": {"kind": "axis", "axis": "z"},
    "mounting_plane": {"kind": "plane", "normal": "primary_axis"}
  },
  "parameters": {
    "outer_radius": {"value": 50, "unit": "mm", "editable": true, "role": "outer_radius"},
    "plate_thickness": {"value": 4, "unit": "mm", "editable": true, "role": "plate_thickness"},
    "bore_diameter": {"value": 20, "unit": "mm", "editable": true, "role": "bore_diameter"},
    "hub_radius": {"value": 16, "unit": "mm", "editable": true, "role": "hub_radius"},
    "hub_height": {"value": 1, "unit": "mm", "editable": true, "role": "hub_height"},
    "hole_count": {"value": 8, "unit": "count", "editable": true, "role": "hole_count"},
    "hole_diameter": {"value": 3.4, "unit": "mm", "editable": true, "role": "clearance_hole_diameter"},
    "bolt_circle_diameter": {"value": 80, "unit": "mm", "editable": true, "role": "bolt_circle_diameter"}
  },
  "expressions": {
    "total_height": "plate_thickness + hub_height"
  },
  "sketches": [],
  "constraints": [
    {"id": "shared_axis", "kind": "concentric", "participants": ["base_flange", "raised_hub", "central_bore", "mounting_pattern"]},
    {"id": "uniform_pattern", "kind": "equal_angular_spacing", "participants": ["mounting_pattern"]}
  ],
  "features": [
    {"id": "base_flange", "operation": "extrude_circle", "radius": {"parameter": "outer_radius"}, "height": {"parameter": "plate_thickness"}, "axis": "primary_axis"},
    {"id": "raised_hub", "operation": "add_cylinder", "radius": {"parameter": "hub_radius"}, "height": {"parameter": "hub_height"}, "center": [0, 0, 4], "axis": "primary_axis"},
    {"id": "central_bore", "operation": "through_hole", "diameter": {"parameter": "bore_diameter"}, "axis": "primary_axis", "host": "base_flange"},
    {"id": "mounting_pattern", "operation": "polar_hole_pattern", "count": {"parameter": "hole_count"}, "diameter": {"parameter": "hole_diameter"}, "pitch_diameter": {"parameter": "bolt_circle_diameter"}, "axis": "primary_axis", "host": "base_flange"}
  ],
  "patterns": [
    {"feature": "mounting_pattern", "kind": "polar", "axis": "primary_axis"}
  ],
  "attachments": [
    {"feature": "raised_hub", "host": "base_flange", "relation": "face_attached"}
  ],
  "construction_stages": [
    {"id": "primary_envelope", "feature_ids": ["base_flange", "raised_hub"]},
    {"id": "passages", "feature_ids": ["central_bore", "mounting_pattern"]}
  ],
  "edit_interface": {
    "editable_parameters": ["outer_radius", "plate_thickness", "bore_diameter", "hub_radius", "hub_height", "hole_count", "hole_diameter", "bolt_circle_diameter"],
    "preserved_interfaces": ["part_center", "primary_axis", "mounting_plane"]
  },
  "validation_contract": {
    "invariants": [
      {"kind": "single_closed_solid"},
      {"kind": "concentric", "participants": ["base_flange", "central_bore"]},
      {"kind": "equal_angular_spacing", "feature": "mounting_pattern"}
    ],
    "perturbations": [
      {"parameter": "plate_thickness", "scale": 1.1, "expected_change": "overall_height_increases", "preserve": ["outer_radius", "hole_count"]},
      {"parameter": "bolt_circle_diameter", "scale": 1.15, "expected_change": "mounting_pattern_radius_increases", "preserve": ["outer_radius", "bore_diameter"]},
      {"parameter": "hole_count", "scale": 1.125, "expected_change": "mounting_hole_count_changes", "preserve": ["outer_radius", "bore_diameter"]}
    ],
    "thresholds": {
      "relative_volume_error_max": 0.01,
      "symmetric_difference_ratio_max": 0.02
    }
  },
  "experience": {"promoted_method_ids": []},
  "confidence": {"family": 1.0, "features": 1.0, "parameters": 1.0}
}