{
  "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": "free-fall",
    "version": "1.0.1",
    "title": "Free Fall Calculator",
    "formula_family": "free-fall",
    "capability_id": "physics.kinematics.free_fall"
  },
  "profile": "engineering",
  "status": "VERIFIED",
  "verification_status": "VERIFIED",
  "production_freshness": "CURRENT",
  "overall_trust": "VERIFIED",
  "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": "free-fall",
    "version": "1.0.1",
    "uri": "https://www.calculatorx.com/evidence/physics.kinematics.free_fall/1.0.1.json"
  },
  "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-IFACE-01"
  ],
  "provenance": {
    "mode": "direct",
    "sources": [
      {
        "label": "Intro physics / NIST units",
        "kind": "other",
        "reference": "standard relations"
      },
      {
        "label": "CGPM / standard gravity gₙ",
        "kind": "standard",
        "reference": "gₙ = 9.80665 m/s²"
      }
    ]
  },
  "reference": {
    "items": [
      {
        "class": "O1",
        "reference_scope": "model",
        "scope": "model",
        "label": "Free fall under constant g"
      },
      {
        "class": "O2",
        "reference_scope": "expected_values",
        "scope": "expected_values",
        "label": "Separate-module free-fall oracle — same V8 binary64 as IUT",
        "engine": {
          "name": "free-fall-reference",
          "precision_bits": 53,
          "independent_of_iut": true
        }
      },
      {
        "class": "O2",
        "reference_scope": "numerical_behavior",
        "scope": "numerical_behavior",
        "label": "Same O2 module backs ≤2 ULP s/v/t comparison vs IUT",
        "engine": {
          "name": "free-fall-reference",
          "precision_bits": 53,
          "independent_of_iut": true
        }
      }
    ],
    "notes": "Golden expected values use a separate O2 module (not IUT transcription). O2 shares Node/V8 binary64 with the IUT unless noted otherwise."
  },
  "controls": {
    "CVP-PROV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Sources present on evidence"
    },
    "CVP-MODEL-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "v=u+gt; s=ut+½gt²; g default 9.80665"
    },
    "CVP-SCOPE-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Constant g; no drag"
    },
    "CVP-UNIT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "m, s, m/s"
    },
    "CVP-REF-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "O1 model + O2 expected_values + O2 numerical_behavior"
    },
    "CVP-GOLD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "1/1 legacy golden; 1/1 oracle-backed numeric"
    },
    "CVP-BND-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "1/1 CVP boundary · 1/1 legacy Evidence boundary"
    },
    "CVP-INV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "1 invalid-domain cases"
    },
    "CVP-NUM-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "max_error_observed_ulp=0; policy declared a priori"
    },
    "CVP-COV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "2/2 declared partitions (fall, invalid-domain) · 1 legacy golden / 1 CVP boundary unique cases · 1 Evidence invalid-input (may overlap boundary)"
    },
    "CVP-CONTRACT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "6/6 CVP contract · release-artifacts-aligned=PASS · schema-output-required-declared=PASS · schema-valid-input-executes=PASS · engine-success-output-validates-schema=PASS · schema-rejects-incomplete-input=PASS · rest-success-payload-validates-schema=PASS"
    },
    "CVP-DEP-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "engine free-fall; 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": "this calculator CURRENT · bound snapshot pass @ 2026-09-21T17:58:01.493Z · live site-wide report stale @ 2026-09-21T17:58:03.268Z (2 other capabilities) · local checks pass · attestation_id=c17d707e2d68ca8a4f9cf99a4adf32d737cc789084d3c7df39311265d8606b4b · This calculator CURRENT · This calculator is not affected · Bound attestation PASS @ 2026-09-21T17:58:01.493Z · Live production status STALE (2 capabilities; 163 remain CURRENT) @ 2026-09-21T17:58:03.268Z · Public schema 1.0.1 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓ · schema_const=1.0.1 · 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 · calculator-html-cvp-projection=pass · evidence-html-cvp-projection=pass · attested_evidence_sha256=e61b4037d1041f3241b94b54f5ce66f4bbccdb745b50cdcabfca5d0f1a01f68d · verified_at=2026-09-10T03:41:45.661Z · evidence_attested_at=2026-09-10T03:41:45.661Z · last_confirmed_current_at=2026-09-21T17:58:01.493Z · rendered_at=2026-09-21T17:58:03.317Z · binds=cvp_core_sha256",
      "check_result": "PASS",
      "production_state": "CURRENT",
      "binding_current": true
    },
    "CVP-DIM-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "Free-fall kinematics"
    },
    "CVP-PROP-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "1/1 property"
    },
    "CVP-META-01": {
      "result": "SKIP",
      "applicability": "not_applicable",
      "notes": "No input→output transformation vectors in pack — control not in obligation set"
    },
    "CVP-ROUND-01": {
      "result": "SKIP",
      "applicability": "not_applicable",
      "notes": "No inverse / round-trip vectors in pack — control not in obligation set"
    },
    "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."
    },
    "CVP-ORACLE-01": {
      "result": "SKIP",
      "applicability": "higher_assurance",
      "notes": "O2 present; O3 not required this wave"
    },
    "CVP-EXP-01": {
      "result": "SKIP",
      "applicability": "optional",
      "notes": "CalculatorX internal domain review — not CVP-EXP-01"
    }
  },
  "tests": {
    "golden": {
      "passed": 1,
      "total": 1,
      "failed": 0,
      "case_ids": [
        "g-s"
      ]
    },
    "boundary": {
      "passed": 1,
      "total": 1,
      "failed": 0,
      "case_ids": [
        "bad"
      ]
    },
    "invalid": {
      "passed": 1,
      "total": 1,
      "failed": 0,
      "case_ids": [
        "bad"
      ]
    },
    "property": {
      "passed": 1,
      "total": 1,
      "failed": 0,
      "case_ids": [
        "property-ff-g"
      ],
      "kind": "fixed"
    },
    "round_trip": {
      "passed": 0,
      "total": 0,
      "failed": 0,
      "case_ids": []
    },
    "metamorphic": {
      "passed": 0,
      "total": 0,
      "failed": 0,
      "case_ids": []
    },
    "contract": {
      "passed": 6,
      "total": 6,
      "failed": 0
    },
    "cross_interface": {
      "passed": 1,
      "total": 1,
      "failed": 0,
      "case_ids": [
        "iface-s"
      ]
    }
  },
  "coverage": {
    "partitions": [
      {
        "id": "fall",
        "description": "free-fall solve",
        "exercised": true,
        "case_count": 3
      },
      {
        "id": "invalid-domain",
        "description": "Invalid inputs",
        "exercised": true,
        "case_count": 1
      }
    ]
  },
  "numerical": {
    "representation": "IEEE-754 binary64",
    "tolerance": {
      "type": "ulp",
      "value": 2,
      "rationale": "Free fall with g; ≤2 ULP vs O2. Declared a priori.",
      "declared_before_evaluation": true
    },
    "max_error_observed": 0,
    "records": [
      {
        "id": "g-s",
        "reference": {
          "mode": "s",
          "u_m_s": 0,
          "g_m_s2": 9.80665,
          "t_s": 2,
          "s_m": 19.6133
        },
        "actual": {
          "mode": "s",
          "u_m_s": 0,
          "g_m_s2": 9.80665,
          "t_s": 2,
          "s_m": 19.6133
        },
        "error_ulp": 0,
        "threshold_ulp": 2
      }
    ]
  },
  "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."
  },
  "artifacts": {
    "evidence_bundle_sha256": "bf37574a17e7c0b83b098304e7f2a19cb9b0a3187bf37426480a1ee0f98dad62",
    "evidence_digest": "794cf278f6df5df2a51a48454508f42f888d0f5cdca1443f0ca77e5fc4ac0de1",
    "production_sha256": "e61b4037d1041f3241b94b54f5ce66f4bbccdb745b50cdcabfca5d0f1a01f68d",
    "attested_catalog_sha256": "8d46aa5f63bae7e6f90d602c9de77b91bd00c35c2c0bb62517d53168143e2256",
    "production_checks": [
      {
        "id": "physics.kinematics.free_fall:output-const",
        "status": "pass",
        "detail": "output const 1.0.1 vs capability 1.0.1",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      },
      {
        "id": "physics.kinematics.free_fall:evidence-sha256",
        "status": "pass",
        "detail": "7bee599c8072",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      },
      {
        "id": "physics.kinematics.free_fall:semantic-contract",
        "status": "pass",
        "detail": "3/3",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      },
      {
        "id": "physics.kinematics.free_fall:capability-html-public-origin-agree",
        "status": "pass",
        "detail": "public 1.0.1 vs origin 1.0.1",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      },
      {
        "id": "physics.kinematics.free_fall:cvp-manifest-public-origin-agree",
        "status": "pass",
        "detail": "physics.kinematics.free_fall/1.0.1/-/engineering/794cf278f6df",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z",
        "projection_compared": false
      },
      {
        "id": "physics.kinematics.free_fall:cvp-latest-alias-agrees",
        "status": "pass",
        "detail": "physics.kinematics.free_fall/1.0.1/-/engineering/794cf278f6df",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z",
        "projection_compared": false
      },
      {
        "id": "physics.kinematics.free_fall:calculator-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      },
      {
        "id": "physics.kinematics.free_fall:evidence-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T03:41:45.661Z"
      }
    ],
    "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": "794cf278f6df5df2a51a48454508f42f888d0f5cdca1443f0ca77e5fc4ac0de1",
          "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": "794cf278f6df5df2a51a48454508f42f888d0f5cdca1443f0ca77e5fc4ac0de1",
          "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": "7bee599c8072d9a2107aec728cef6cf1fa5e9f279f15c3ba99854082dff4d023",
          "note": "Published Evidence JSON core — Trust freshness / production bind subject"
        },
        {
          "name": "evidence_catalog_digest",
          "field": "artifacts.attested_catalog_sha256",
          "digest_scope": "capability_catalog",
          "value": "8d46aa5f63bae7e6f90d602c9de77b91bd00c35c2c0bb62517d53168143e2256",
          "note": "Capability catalog integrity; site-wide, not per-suite fingerprint"
        }
      ]
    },
    "cvp_core_sha256": "794cf278f6df5df2a51a48454508f42f888d0f5cdca1443f0ca77e5fc4ac0de1"
  },
  "dependencies": [
    {
      "name": "free-fall-engine",
      "version": "1.0.1"
    },
    {
      "name": "free-fall-reference-oracle",
      "version": "1.0.0"
    },
    {
      "name": "node",
      "version": "20.19.2"
    }
  ],
  "attestation": {
    "status": "CURRENT",
    "href": "/.well-known/calculatorx-production-attestation.json",
    "id": "c17d707e2d68ca8a4f9cf99a4adf32d737cc789084d3c7df39311265d8606b4b",
    "attested_at": "2026-09-10T03:41:45.661Z",
    "last_confirmed_current_at": "2026-09-21T17:58:01.493Z",
    "site_attestation_current": false,
    "capability_attestation_current": true,
    "bound_snapshot_status": "pass",
    "live_report_status": "stale",
    "bound_attested_at": "2026-09-21T17:58:01.493Z",
    "live_updated_at": "2026-09-21T17:58:03.268Z",
    "bound_snapshot": {
      "status": "pass",
      "attested_at": "2026-09-21T17:58:01.493Z",
      "site_stale_count": 2
    },
    "live_site_status": {
      "href": "/.well-known/calculatorx-production-attestation.json"
    },
    "bound_snapshot_site_stale_count": 2,
    "site_stale_capability_count": 2,
    "evidence_attested_at": "2026-09-10T03:41:45.661Z"
  },
  "domain_review": {
    "status": "ABSENT",
    "spec_version": "1.0.1",
    "external_third_party": false,
    "note": "Supplemental CalculatorX internal domain review — see internal_review"
  },
  "internal_review": {
    "status": "PASS",
    "reviewed_by": "CalculatorX physics review",
    "spec_version": "1.0.1",
    "independence": "internal",
    "external_third_party": false
  },
  "timestamps": {
    "verified_at": "2026-09-10T03:41:45.661Z",
    "generated_at": "2026-09-10T03:41:45.661Z",
    "rendered_at": "2026-09-21T17:58:03.317Z",
    "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."
  },
  "links": {
    "legacy_evidence": "https://www.calculatorx.com/evidence/physics.kinematics.free_fall/1.0.1.json",
    "evidence_page": "https://www.calculatorx.com/evidence/physics.kinematics.free_fall/1.0.1",
    "calculator": "https://www.calculatorx.com/calc/physics/free-fall",
    "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/physics.kinematics.free_fall/1.0.1.cvp.json"
  }
}