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  "passed": 15,
  "failed": 0,
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      "total": 1,
      "passed": 1
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    "boundary": {
      "total": 9,
      "passed": 9
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    "property": {
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      "passed": 5
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  "engine_tested": true,
  "expert_reviewed": false,
  "internally_reviewed": false,
  "review_kind": null,
  "source_checked": true,
  "reviewed_by": null,
  "reviewer_role": null,
  "last_reviewed": null,
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    "reviewer": null,
    "scope": [
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      "input semantics",
      "assumptions",
      "limitations",
      "sources",
      "tests"
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  "assumptions": [
    "Thin-plate weir; free nappe",
    "SI g=9.80665 unless given",
    "Rectangular: Q=(2/3) C_d L √(2g) H^{3/2}; not Francis contractions",
    "Triangular: Q=(8/15) C_d √(2g) tan(θ/2) H^{5/2}",
    "Not Manning, not Q=Av, not Darcy, not an orifice"
  ],
  "limitations": [
    "Thin-plate weir; free nappe; SI g=9.80665 unless given",
    "Rectangular: Q=(2/3) C_d L √(2g) H^{3/2}; not Francis contractions",
    "Triangular: Q=(8/15) C_d √(2g) tan(θ/2) H^{5/2}",
    "Not Manning, not Q=Av, not Darcy, not an orifice"
  ],
  "boundary_conditions": [
    "missing H or Q → MISSING_REQUIRED_INPUT",
    "rectangular missing L → MISSING_REQUIRED_INPUT",
    "H, Q, L, Cd, θ, or g ≤ 0 → VALUE_MUST_BE_POSITIVE",
    "H and Q together, or θ_deg and θ_rad → MIXED_INPUT_ENCODING",
    "C_d > 1 → VALUE_OUT_OF_RANGE",
    "Francis, Cipolletti, Manning, or orifice as mode → INVALID_MODE"
  ],
  "sources": [
    {
      "title": "ISO 1438 — Hydrometry — Open channel flow measurement using thin-plate weirs",
      "section": "Rectangular and triangular thin-plate weirs",
      "url": "https://www.iso.org/standard/41711.html",
      "supports": "Thin-plate weir discharge from head over a sharp crest",
      "kind": "standard"
    },
    {
      "title": "ISO 80000-4 — Mechanics",
      "section": "Volume flow rate",
      "url": "https://www.iso.org/standard/31895.html",
      "supports": "Q is volume flow; H is a length (head)",
      "kind": "standard"
    },
    {
      "title": "Chow, V.T. Open-Channel Hydraulics",
      "section": "Sharp-crested weirs",
      "supports": "Rectangular (2/3) C_d L √(2g) H^{3/2}; triangular (8/15) C_d √(2g) tan(θ/2) H^{5/2}",
      "kind": "reference"
    }
  ],
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  "fingerprint": "sha256:89f4b29e1866ab5aebf1de5dc2f8ea3977fde29a6c9c321d2824d2b28b459b96",
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      "id": "golden-weir-rect",
      "ok": true,
      "kind": "golden",
      "inputs": {
        "L": 1,
        "H": 0.2
      },
      "expect": {
        "Q": 0.163727171653876,
        "H": 0.2,
        "Cd": 0.62,
        "L": 1,
        "mode": "rectangular",
        "model": "thin_plate_weir"
      },
      "expectWarning": null,
      "actual": {
        "mode": "rectangular",
        "Q": 0.163727171653876,
        "H": 0.2,
        "Cd": 0.62,
        "g": 9.80665,
        "L": 1,
        "model": "thin_plate_weir"
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      "tol": 1e-10
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      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "Q": 0.163727171653876
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      "expect": {
        "H": 0.2,
        "model": "thin_plate_weir"
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      "expectWarning": null,
      "actual": {
        "mode": "rectangular",
        "Q": 0.163727171653876,
        "H": 0.20000000000000004,
        "Cd": 0.62,
        "g": 9.80665,
        "L": 1,
        "model": "thin_plate_weir"
      },
      "tol": 1e-10
    },
    {
      "id": "boundary-weir-tri",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "mode": "triangular",
        "H": 0.2
      },
      "expect": {
        "Q": 0.024506260531418852,
        "Cd": 0.58,
        "theta_deg": 90,
        "mode": "triangular",
        "model": "thin_plate_weir"
      },
      "expectWarning": null,
      "actual": {
        "mode": "triangular",
        "Q": 0.024506260531418852,
        "H": 0.2,
        "Cd": 0.58,
        "g": 9.80665,
        "theta_deg": 90,
        "model": "thin_plate_weir"
      },
      "tol": 1e-10
    },
    {
      "id": "boundary-weir-missing",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1
      },
      "expectError": "MISSING_REQUIRED_INPUT",
      "code": "MISSING_REQUIRED_INPUT",
      "error": "H is required"
    },
    {
      "id": "boundary-weir-h0",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "H": 0
      },
      "expectError": "VALUE_MUST_BE_POSITIVE",
      "code": "VALUE_MUST_BE_POSITIVE",
      "error": "H must be greater than zero"
    },
    {
      "id": "boundary-weir-mixed",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "H": 0.2,
        "Q": 0.163727171653876
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Give H or Q, not both"
    },
    {
      "id": "boundary-weir-francis-cd",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "H": 0.2,
        "Cd": 3.33
      },
      "expectError": "VALUE_OUT_OF_RANGE",
      "code": "VALUE_OUT_OF_RANGE",
      "error": "Cd must be ≤ 1"
    },
    {
      "id": "boundary-weir-francis",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "H": 0.2,
        "mode": "francis"
      },
      "expectError": "INVALID_MODE",
      "code": "INVALID_MODE",
      "error": "mode must be rectangular|triangular. Not Francis, Cipolletti, Manning, or orifice"
    },
    {
      "id": "boundary-weir-orifice",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "L": 1,
        "H": 0.2,
        "mode": "orifice"
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      "expectError": "INVALID_MODE",
      "code": "INVALID_MODE",
      "error": "mode must be rectangular|triangular. Not Francis, Cipolletti, Manning, or orifice"
    },
    {
      "id": "boundary-weir-manning",
      "ok": true,
      "kind": "boundary",
      "inputs": {
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        "H": 0.2,
        "mode": "manning"
      },
      "expectError": "INVALID_MODE",
      "code": "INVALID_MODE",
      "error": "mode must be rectangular|triangular. Not Francis, Cipolletti, Manning, or orifice"
    },
    {
      "id": "property-weir-q",
      "ok": true,
      "kind": "property",
      "detail": "rect Q=(2/3)Cd L √(2g) H^{3/2}",
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    {
      "id": "property-weir-h",
      "ok": true,
      "kind": "property",
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      "expect": 0.2,
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      "ok": true,
      "kind": "property",
      "detail": "90° V-notch",
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      "actual": 0.024506260531418852
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      "id": "property-weir-cd",
      "ok": true,
      "kind": "property",
      "detail": "default Cd 0.62/0.58",
      "expect": 0.62,
      "actual": 0.62
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      "ok": true,
      "kind": "property",
      "detail": "thin_plate_weir",
      "expect": true,
      "actual": "thin_plate_weir"
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      "passed": 15,
      "total": 15,
      "golden": 1,
      "boundary": 9,
      "property": 5
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