{
  "protocol": {
    "name": "CVP",
    "version": "1.0.0-proposed",
    "revision": "2026-09-13",
    "spec_sha256": "f62725968356c92930531cd6085db76e216da06e95be53d636b0d2cf3218b148",
    "spec": "https://www.calculatorx.com/developers/cvp/spec/1.0"
  },
  "document_status": "proposed",
  "calculator": {
    "id": "percent-error",
    "version": "1.1.4",
    "title": "Percent Error Calculator",
    "formula_family": "percent_error",
    "capability_id": "math.percent_error",
    "verification_revision": "2026-10-13.percent-error-replay-review"
  },
  "profile": "engineering",
  "status": "STALE",
  "verification_status": "VERIFIED",
  "production_freshness": "STALE",
  "overall_trust": "VERIFIED_STALE",
  "runner": {
    "name": "cvp-runner",
    "version": "1.0.0"
  },
  "environment": {
    "runtime": "node",
    "runtime_version": "20.19.2",
    "numeric_model": "IEEE-754 binary64",
    "os": "darwin"
  },
  "suite": {
    "id": "percent-error",
    "version": "1.1.4",
    "uri": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4.json",
    "verification_revision": "2026-10-13.percent-error-replay-review"
  },
  "obligation_set": [
    "CVP-PROV-01",
    "CVP-MODEL-01",
    "CVP-SCOPE-01",
    "CVP-UNIT-01",
    "CVP-REF-01",
    "CVP-GOLD-01",
    "CVP-BND-01",
    "CVP-INV-01",
    "CVP-NUM-01",
    "CVP-COV-01",
    "CVP-CONTRACT-01",
    "CVP-DEP-01",
    "CVP-ART-01",
    "CVP-PROD-01",
    "CVP-DIM-01",
    "CVP-PROP-01",
    "CVP-META-01",
    "CVP-ROUND-01",
    "CVP-IFACE-01"
  ],
  "provenance": {
    "mode": "direct",
    "sources": [
      {
        "label": "JCGM 200:2012 — International vocabulary of metrology (VIM)",
        "kind": "other",
        "reference": "§2.16 measurement error",
        "url": "https://www.bipm.org/en/committees/jc/jcgm/publications"
      },
      {
        "label": "NIST Dataplot PERCERR",
        "kind": "other",
        "reference": "Percent error of a true/accepted value vs an observed value",
        "url": "https://www.itl.nist.gov/div898/software/dataplot/refman2/auxillar/percerr.htm"
      },
      {
        "label": "NIST Dataplot RELERR",
        "kind": "other",
        "reference": "Relative error of a true/accepted value vs an observed value",
        "url": "https://www.itl.nist.gov/div898/software/dataplot/refman2/auxillar/relerr.htm"
      },
      {
        "label": "CalculatorX laboratory convention",
        "kind": "other",
        "reference": "Absolute-value percent error, signed opt-in, and reverse-solve states"
      }
    ]
  },
  "controls": {
    "CVP-PROV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Sources present on evidence"
    },
    "CVP-MODEL-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "|O−T|/|T|×100% (signed opt-in); inverse publishes the full candidate set"
    },
    "CVP-SCOPE-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "T≠0; solve_for p|o|t; all three fields verify; absolute reverse-solves are multi-valued"
    },
    "CVP-UNIT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "percent"
    },
    "CVP-REF-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "O1 model + O2 expected_values + O2 numerical_behavior"
    },
    "CVP-GOLD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "10/10 legacy golden; 22/22 oracle-backed numeric"
    },
    "CVP-BND-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "4/4 CVP boundary · 4/4 legacy Evidence boundary"
    },
    "CVP-INV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "4 Evidence illegal-input + 8/8 oracle-backed error-code (exact_error_match, not ULP)"
    },
    "CVP-NUM-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "max_error_observed_ulp=1; policy declared a priori"
    },
    "CVP-COV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "5/5 declared partitions (forward, inverse-observed, inverse-true, verify, invalid-domain) · 10 legacy golden / 4 CVP boundary unique cases · 4 Evidence invalid-input (may overlap boundary)"
    },
    "CVP-CONTRACT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "5/5 CVP contract · release-artifacts-aligned=PASS · schema-output-required-declared=PASS · schema-valid-input-executes=PASS · engine-success-output-validates-schema=PASS · rest-success-payload-validates-schema=PASS"
    },
    "CVP-DEP-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "engine percent-error; Node binary64"
    },
    "CVP-ART-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "release_integrity.status=verified · digests: artifact_evidence_sha256=Evidence core (Trust freshness) · cvp_evidence_digest=artifacts.evidence_digest (fingerprint v2) · evidence_bundle_sha256=legacy Evidence JSON bytes · evidence_catalog_digest=attested_catalog_sha256 · production_sha256=bound production report · see artifacts.digest_registry"
    },
    "CVP-PROD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Capability production binding: STALE · Site report: stale · STALE (freshness / digest drift after last PASS snapshot) · site report stale · local checks pass · local production checks PASS; capability production binding is not CURRENT — final status must stay STALE, not VERIFIED · attestation_id=b6db86a3946922a6529492107ca8043828115b3ffd21d9c4669ff69fb7f854ce · previous live site report said CURRENT · This calculator is not affected · Bound attestation PASS @ 2026-09-29T09:41:45.368Z · Live production status STALE (17 capabilities; 359 remain CURRENT) @ 2026-10-12T13:25:12.946Z · Public schema 1.1.4 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓ · schema_const=1.1.4 · report output-const=pass · evidence-sha256=pass · semantic-contract=pass · capability-html-public-origin-agree=pass · cvp-manifest-public-origin-agree=pass · cvp-latest-alias-agrees=pass · cvp-reproduce-manifest-agree=pass · calculator-html-cvp-projection=pass · evidence-html-cvp-projection=pass · attested_evidence_sha256=8a224dbdcd21223942d0e73df9a3c58e3b2c63d744bd5164790a86cc92da0fc9 · verified_at=2026-10-12T22:12:57.275Z · evidence_attested_at=2026-10-12T22:12:57.275Z · last_confirmed_current_at=2026-10-12T22:12:57.275Z · rendered_at=2026-10-12T22:12:57.275Z · binds=cvp_core_sha256 · attestation snapshot core e527121b29b3 ≠ live cvp_core_sha256 630a2997f606 (2026-10-13.percent-error-replay-review)",
      "check_result": "PASS",
      "production_state": "STALE",
      "binding_current": false
    },
    "CVP-DIM-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "relative measurement error"
    },
    "CVP-PROP-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "3/3 property"
    },
    "CVP-META-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "1/1 metamorphic"
    },
    "CVP-ROUND-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "7/7 round-trips"
    },
    "CVP-XCAL-01": {
      "result": "SKIP",
      "applicability": "not_applicable",
      "notes": "No related calculator in the same formula family / no related-identity peers declared — control not in obligation set"
    },
    "CVP-IFACE-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 8/8 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only."
    },
    "CVP-ORACLE-01": {
      "result": "SKIP",
      "applicability": "higher_assurance",
      "notes": "O2 present; O3 not required this wave"
    },
    "CVP-EXP-01": {
      "result": "SKIP",
      "applicability": "optional",
      "notes": "named expert review not performed"
    }
  },
  "interfaces": {
    "compared": [
      "ui-ssr",
      "rest",
      "mcp"
    ],
    "result": "PASS",
    "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 8/8 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only."
  },
  "artifacts": {
    "evidence_bundle_sha256": "d80253ab2fd0a9e028225177abc25a00a0eda058d7f6485069b98297d152b290",
    "evidence_digest": "630a2997f606dfdf4f2e77cf572127a4cab4d8c2615c0eb32b00d6d7f17c1f5a",
    "production_sha256": "8a224dbdcd21223942d0e73df9a3c58e3b2c63d744bd5164790a86cc92da0fc9",
    "attested_catalog_sha256": "6186d9f9c642e2b117ca4b72014d212f663656bb36624b7c12dbc67c29ee9f34",
    "production_checks": [
      {
        "id": "math.percent_error:output-const",
        "status": "pass",
        "detail": "output const 1.1.4 vs capability 1.1.4",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:evidence-sha256",
        "status": "pass",
        "detail": "1720f24bd4ab",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:semantic-contract",
        "status": "pass",
        "detail": "14/14",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:capability-html-public-origin-agree",
        "status": "pass",
        "detail": "public 1.1.4 vs origin 1.1.4",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:cvp-manifest-public-origin-agree",
        "status": "pass",
        "detail": "math.percent_error/1.1.4/2026-10-13.percent-error-replay-review/engineering/630a2997f606",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core",
        "projection_compared": false
      },
      {
        "id": "math.percent_error:cvp-latest-alias-agrees",
        "status": "pass",
        "detail": "math.percent_error/1.1.4/2026-10-13.percent-error-replay-review/engineering/630a2997f606",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core",
        "projection_compared": false
      },
      {
        "id": "math.percent_error:cvp-reproduce-manifest-agree",
        "status": "pass",
        "detail": "O3 reproduce not applicable",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:calculator-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      },
      {
        "id": "math.percent_error:evidence-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": false,
        "attestation_binding_current": false,
        "attested_at": "2026-10-12T22:12:57.275Z",
        "attestation_revision": "core"
      }
    ],
    "digest_registry": {
      "digest_algorithm": "sha256",
      "canonicalization": "json-sorted-keys-utf8",
      "entries": [
        {
          "name": "cvp_core_sha256",
          "field": "artifacts.cvp_core_sha256",
          "digest_scope": "cvp_verification_fingerprint_v2",
          "value": "630a2997f606dfdf4f2e77cf572127a4cab4d8c2615c0eb32b00d6d7f17c1f5a",
          "note": "Immutable verification core; excludes attestation/live-status and Evidence contract counts"
        },
        {
          "name": "cvp_evidence_digest",
          "field": "artifacts.evidence_digest",
          "digest_scope": "cvp_verification_fingerprint_v2",
          "value": "630a2997f606dfdf4f2e77cf572127a4cab4d8c2615c0eb32b00d6d7f17c1f5a",
          "note": "Alias of cvp_core_sha256 (historical field name)"
        },
        {
          "name": "artifact_evidence_sha256",
          "field": "release_integrity.digests.evidence_core_sha256",
          "digest_scope": "evidence_artifact_core",
          "value": "1720f24bd4ab5136e251a33a2b39b05dae94fe9a2bab201306909cc6d47d2de3",
          "note": "Published Evidence JSON core — Trust freshness / production bind subject"
        },
        {
          "name": "evidence_catalog_digest",
          "field": "artifacts.attested_catalog_sha256",
          "digest_scope": "capability_catalog",
          "value": "6186d9f9c642e2b117ca4b72014d212f663656bb36624b7c12dbc67c29ee9f34",
          "note": "Capability catalog integrity; site-wide, not per-suite fingerprint"
        }
      ]
    },
    "cvp_core_sha256": "630a2997f606dfdf4f2e77cf572127a4cab4d8c2615c0eb32b00d6d7f17c1f5a"
  },
  "dependencies": [
    {
      "name": "percent-error-engine",
      "version": "1.1.4"
    },
    {
      "name": "percent-error-reference-oracle",
      "version": "1.0.0"
    },
    {
      "name": "node",
      "version": "20.19.2"
    }
  ],
  "attestation": {
    "status": "STALE",
    "href": "/.well-known/calculatorx-production-attestation.json",
    "id": "b6db86a3946922a6529492107ca8043828115b3ffd21d9c4669ff69fb7f854ce",
    "attested_at": "2026-10-12T22:12:57.275Z",
    "last_confirmed_current_at": "2026-10-12T22:12:57.275Z",
    "site_attestation_current": false,
    "capability_attestation_current": false,
    "bound_snapshot_status": "pass",
    "live_report_status": "stale",
    "bound_attested_at": "2026-09-29T09:41:45.368Z",
    "live_updated_at": "2026-10-12T13:25:12.946Z",
    "bound_snapshot": {
      "status": "pass",
      "attested_at": "2026-09-29T09:41:45.368Z",
      "site_stale_count": 17
    },
    "live_site_status": {
      "href": "/.well-known/calculatorx-production-attestation.json"
    },
    "bound_snapshot_site_stale_count": 17,
    "site_stale_capability_count": 17,
    "evidence_attested_at": "2026-10-12T22:12:57.275Z",
    "stale_reason": "attestation snapshot core e527121b29b3 ≠ live cvp_core_sha256 630a2997f606 (2026-10-13.percent-error-replay-review)"
  },
  "domain_review": {
    "status": "ABSENT",
    "spec_version": "1.1.4",
    "external_third_party": false,
    "note": "Named expert review not performed"
  },
  "timestamps": {
    "verified_at": "2026-10-12T22:12:57.275Z",
    "generated_at": "2026-10-12T22:12:57.275Z",
    "rendered_at": "2026-10-12T22:12:57.275Z",
    "notes": "verified_at/generated_at mark the first publication of this cvp_core_sha256 (artifacts.evidence_digest alias) for suite verification. evidence_attested_at/attested_at is the first production bind of that core digest. last_confirmed_current_at is the latest site-wide report that still confirms CURRENT. rendered_at is this JSON serialization and is not part of cvp_core_sha256 / evidence_digest. Production attestation binds cvp_core_sha256 (binds evidence_digest). Causal order: verified_at ≤ evidence_attested_at ≤ last_confirmed_current_at. attestation.bound_snapshot.site_stale_count is the site-wide stale capability count at Manifest bind time — not a live value. Fetch attestation.live_site_status.href for the current site report."
  },
  "tests": {
    "golden": {
      "passed": 22,
      "total": 22,
      "failed": 0
    },
    "boundary": {
      "passed": 4,
      "total": 4,
      "failed": 0
    },
    "invalid": {
      "passed": 12,
      "total": 12,
      "failed": 0,
      "comparison": "exact_error_match"
    },
    "property": {
      "passed": 3,
      "total": 3,
      "failed": 0
    },
    "round_trip": {
      "passed": 7,
      "total": 7,
      "failed": 0
    },
    "metamorphic": {
      "passed": 1,
      "total": 1,
      "failed": 0
    },
    "contract": {
      "passed": 5,
      "total": 5,
      "failed": 0
    },
    "cross_interface": {
      "passed": 30,
      "total": 30,
      "failed": 0
    }
  },
  "numerical": {
    "representation": "IEEE-754 binary64 percent error",
    "tolerance": {
      "type": "ulp",
      "value": 2,
      "rationale": "Independent |O−T|/|T|×100 vs IUT; ≤2 ULP on value and each inverse candidate. Declared a priori.",
      "declared_before_evaluation": true
    },
    "max_error_observed": 1
  },
  "coverage": {
    "partitions": [
      {
        "id": "forward",
        "description": "Forward |O−T|/|T|×100%",
        "exercised": true,
        "case_count": 20
      },
      {
        "id": "inverse-observed",
        "description": "Solve observed O",
        "exercised": true,
        "case_count": 8
      },
      {
        "id": "inverse-true",
        "description": "Solve accepted T",
        "exercised": true,
        "case_count": 10
      },
      {
        "id": "verify",
        "description": "Three-field verify",
        "exercised": true,
        "case_count": 5
      },
      {
        "id": "invalid-domain",
        "description": "Invalid inputs",
        "exercised": true,
        "case_count": 12
      }
    ]
  },
  "reference": {
    "items": [
      {
        "class": "O1",
        "reference_scope": "model",
        "scope": "model",
        "label": "Laboratory percent error vs accepted value"
      },
      {
        "class": "O2",
        "reference_scope": "expected_values",
        "scope": "expected_values",
        "label": "Separate-module percent-error oracle (full inverse solution set)",
        "engine": {
          "name": "percent-error-reference",
          "precision_bits": 53,
          "independent_of_iut": true,
          "same_runtime_as_iut": true
        }
      },
      {
        "class": "O2",
        "reference_scope": "numerical_behavior",
        "scope": "numerical_behavior",
        "label": "Same O2 module backs ≤2 ULP value and candidate-set comparison vs IUT",
        "engine": {
          "name": "percent-error-reference",
          "precision_bits": 53,
          "independent_of_iut": true,
          "same_runtime_as_iut": true
        }
      }
    ]
  },
  "links": {
    "legacy_evidence": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4.json",
    "evidence_page": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4",
    "calculator": "https://www.calculatorx.com/calc/math/percent-error",
    "schema": "https://www.calculatorx.com/developers/cvp/schema/cvp-evidence-1.0.json",
    "protocol": "https://www.calculatorx.com/developers/cvp/spec/1.0",
    "manifest": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4.cvp.json",
    "manifest_immutable": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4/2026-10-13.percent-error-replay-review.cvp.json",
    "reproduce": "https://www.calculatorx.com/evidence/math.percent_error/reproduce",
    "manifest_core": "https://www.calculatorx.com/evidence/math.percent_error/1.1.4/2026-10-13.percent-error-replay-review.630a2997f606.cvp.json"
  },
  "disclosure": {
    "policy": "calculatorx-public-evidence-v1",
    "full_validation": "private",
    "representation": "summary"
  }
}