{
  "capability_id": "engineering.msa.gauge_rr",
  "tool_id": "gauge-rr",
  "engine": "gauge-rr",
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  "generated_at": "2026-09-16T22:38:08.856Z",
  "engine_build": "2026-09-16",
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  "failed": 0,
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      "passed": 1
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    "boundary": {
      "total": 4,
      "passed": 4
    },
    "property": {
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      "passed": 3
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  "engine_tested": true,
  "expert_reviewed": false,
  "internally_reviewed": false,
  "review_kind": null,
  "source_checked": true,
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  "reviewer_role": null,
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    "scope": [
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      "sources",
      "tests"
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    "note": "Domain expert review is optional under CVP (CVP-EXP-01). Absence does not block CVP Verified. See Review policy for supplemental domain assurance."
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  "internal_review": {
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  "page": "https://www.calculatorx.com/calc/engineering/gauge-repeatability-reproducibility",
  "api": "https://www.calculatorx.com/api/v1/calc/gauge-rr",
  "schema_input": "https://www.calculatorx.com/schemas/engineering.msa.gauge_rr.input.json",
  "schema_output": "https://www.calculatorx.com/schemas/engineering.msa.gauge_rr.output.json",
  "assumptions": [
    "AIAG compose: GRR=√(EV²+AV²), TV=√(GRR²+PV²), %GRR=100·GRR/TV, ndc=1.41·PV/GRR",
    "Range-method EV = R̄/d2 (d2 defaults to 1.128 for n=2). Not a full ANOVA Gauge R&R.",
    "Provide ev or rbar, not both"
  ],
  "limitations": [
    "AIAG compose of stated EV, AV, PV — not a full ANOVA Gauge R&R",
    "Range-method EV uses d2 default 1.128 (n=2)",
    "GRR must be > 0 for ndc"
  ],
  "boundary_conditions": [
    "missing ev and rbar → MISSING_REQUIRED_INPUT",
    "both ev and rbar → INVALID_INPUT",
    "GRR=0 → VALUE_MUST_BE_POSITIVE (ndc)",
    "negative EV/AV/PV → VALUE_OUT_OF_RANGE"
  ],
  "sources": [
    {
      "title": "AIAG Measurement Systems Analysis (MSA)",
      "section": "Gauge R&R — %GRR and ndc",
      "supports": "GRR=√(EV²+AV²); %GRR=100·GRR/TV; ndc≈1.41·PV/GRR",
      "kind": "standard"
    },
    {
      "title": "NIST Engineering Statistics Handbook — Repeatability",
      "section": "2.4.5 Repeatability and reproducibility",
      "url": "https://www.itl.nist.gov/div898/handbook/mpc/section4/mpc4.htm",
      "supports": "Range-method equipment variation EV = R̄/d2; d2 for n=2",
      "kind": "reference"
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  "fingerprint": "sha256:b3b98497ba42d897e007438b58bf39c5b25e1fb4218b7c18f6de34c3825fbded",
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    {
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      "ok": true,
      "kind": "golden",
      "inputs": {
        "ev": 3,
        "av": 4,
        "pv": 12
      },
      "expect": {
        "GRR": 5,
        "TV": 13,
        "pct_grr": 38.46153846153846,
        "ndc": 3.384
      },
      "expectWarning": null,
      "actual": {
        "EV": 3,
        "AV": 4,
        "PV": 12,
        "GRR": 5,
        "TV": 13,
        "pct_grr": 38.46153846153846,
        "ndc": 3.3839999999999995
      },
      "tol": 1e-12
    },
    {
      "id": "boundary-grr-range",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "rbar": 1.128,
        "av": 4,
        "pv": 12
      },
      "expect": {
        "EV": 1
      },
      "expectWarning": null,
      "actual": {
        "EV": 1,
        "AV": 4,
        "PV": 12,
        "GRR": 4.123105625617661,
        "TV": 12.688577540449518,
        "pct_grr": 32.49462449572256,
        "ndc": 4.103702775614753,
        "rbar": 1.128,
        "d2": 1.128
      },
      "tol": 1e-12
    },
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      "id": "boundary-grr-both",
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      "kind": "boundary",
      "inputs": {
        "ev": 3,
        "rbar": 1.128,
        "av": 4,
        "pv": 12
      },
      "expectError": "INVALID_INPUT",
      "code": "INVALID_INPUT",
      "error": "provide ev or rbar, not both"
    },
    {
      "id": "boundary-grr-missing",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "av": 4,
        "pv": 12
      },
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      "error": "ev or rbar is required"
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      "code": "VALUE_MUST_BE_POSITIVE",
      "error": "grr must be greater than zero for ndc"
    },
    {
      "id": "property-grr",
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      "kind": "property",
      "detail": "5",
      "expect": 5,
      "actual": 5
    },
    {
      "id": "property-tv",
      "ok": true,
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      "detail": "13",
      "expect": 13,
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    },
    {
      "id": "property-range-ev",
      "ok": true,
      "kind": "property",
      "detail": "1",
      "expect": 1,
      "actual": 1
    }
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  "tier": "engine_tested",
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      "passed": 8,
      "total": 8,
      "golden": 1,
      "boundary": 4,
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  "evidence_core_generated_at": "2026-09-16T21:07:40.795Z",
  "rendered_at": "2026-09-16T22:38:08.856Z",
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