{
  "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": "log",
    "version": "1.1.6",
    "title": "Log Calculator",
    "formula_family": "logarithm",
    "capability_id": "math.log",
    "verification_revision": "2026-10-27.full-review-v3"
  },
  "profile": "core",
  "status": "VERIFIED",
  "verification_status": "VERIFIED",
  "production_freshness": "CURRENT",
  "overall_trust": "VERIFIED",
  "runner": {
    "name": "cvp-runner",
    "version": "1.0.0"
  },
  "environment": {
    "runtime": "node",
    "runtime_version": "22.20.0",
    "numeric_model": "IEEE-754 binary64",
    "os": "darwin"
  },
  "suite": {
    "id": "log",
    "version": "1.1.6",
    "uri": "https://www.calculatorx.com/evidence/math.log/1.1.6.json",
    "verification_revision": "2026-10-27.full-review-v3"
  },
  "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-PROP-01",
    "CVP-META-01",
    "CVP-ROUND-01",
    "CVP-XCAL-01",
    "CVP-IFACE-01"
  ],
  "provenance": {
    "mode": "direct",
    "sources": [
      {
        "label": "NIST Digital Library of Mathematical Functions, Chapter 4",
        "kind": "other",
        "reference": "Logarithm, Exponential, Powers",
        "url": "https://dlmf.nist.gov/4"
      },
      {
        "label": "NIST DLMF §4.2",
        "kind": "other",
        "reference": "Logarithm: definitions and inverse of the exponential",
        "url": "https://dlmf.nist.gov/4.2"
      },
      {
        "label": "CalculatorX mathematical conventions",
        "kind": "other",
        "reference": "Common (base 10), natural (base e), and real bases b > 0, b ≠ 1"
      }
    ]
  },
  "controls": {
    "CVP-PROV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Sources present on evidence"
    },
    "CVP-MODEL-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "y = log_b(x) via change-of-base"
    },
    "CVP-SCOPE-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Real log: x>0; b>0,b≠1"
    },
    "CVP-UNIT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "dimensionless (unitless core)"
    },
    "CVP-REF-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "O1 model + O3 log10 table + O2 live change-of-base"
    },
    "CVP-GOLD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "22/22 legacy golden; 48/48 oracle-backed numeric"
    },
    "CVP-BND-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "23/23 CVP boundary · 23/23 legacy Evidence boundary"
    },
    "CVP-INV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "23 invalid-domain cases"
    },
    "CVP-NUM-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "≤2 ULP vs O3 applies to the 14 published tabulated common-log vectors (log₁₀ of 1, 10, 100, 0.1, 2, 1000 plus 8 seeded random x = 10^(u·6−2) in about [0.01, 10⁴]). It is not a guarantee over all bases, the whole positive reals, or unlisted neighborhoods of 0 and 1. Legacy Evidence `tol` is not this policy."
    },
    "CVP-COV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "5/5 declared partitions (log-y, log-x, log-b, invalid-domain, xcal) · 22 legacy golden / 23 CVP boundary unique cases · 23 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 log; 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 @ 2026-10-28T05:11:56.928Z · live site-wide report stale @ 2026-10-28T05:12:05.151Z (16 other capabilities) · local checks pass · attestation_id=f3abb5d04ebc51171f259234b69628b210f1534445c968974f68a48041bc5e07 · This calculator CURRENT · This calculator is not affected · Bound attestation PASS @ 2026-10-28T05:11:56.928Z · Live production status STALE (16 capabilities; 360 remain CURRENT) @ 2026-10-28T05:12:05.151Z · Public schema 1.1.6 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓ · schema_const=1.1.6 · 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-immutable-manifest-fetch=pass · cvp-immutable-manifest-sha256=pass · cvp-latest-alias-matches-immutable=pass · cvp-reproduce-manifest-agree=pass · calculator-html-cvp-projection=pass · evidence-html-cvp-projection=pass · attested_evidence_sha256=0904162d9842ae579e660eb678ec02f2ca6e852dd03b716905c0a6501acd7dae · verified_at=2026-10-27T02:19:49.883Z · evidence_attested_at=2026-10-27T02:19:49.883Z · last_confirmed_current_at=2026-10-28T05:11:56.928Z · rendered_at=2026-10-28T05:12:28.886Z · binds=cvp_core_sha256",
      "check_result": "PASS",
      "production_state": "CURRENT",
      "binding_current": true
    },
    "CVP-DIM-01": {
      "result": "SKIP",
      "applicability": "not_applicable",
      "notes": "Unitless core calculator — no physical dimension algebra"
    },
    "CVP-PROP-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "2/2 property"
    },
    "CVP-META-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "2/2 metamorphic"
    },
    "CVP-ROUND-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "3/3 round-trips"
    },
    "CVP-XCAL-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "12/12 cross-calculator · xcal-antilog-100 PASS vs math.antilog; xcal-antilog-10 PASS vs math.antilog; xcal-antilog-2 PASS vs math.antilog; xcal-antilog-tenth PASS vs math.antilog; xcal-ln-10 PASS vs math.ln; xcal-ln-2 PASS vs math.ln; xcal-ln-e PASS vs math.ln; xcal-ln-half PASS vs math.ln; xcal-exponent-0 PASS vs math.exponent; xcal-exponent-1 PASS vs math.exponent; xcal-exponent-2 PASS vs math.exponent; xcal-exponent-3 PASS vs math.exponent; xcal-sci-na N/A (Scientific notation is listed as a related decimal-form tool (A×10ⁿ). It does not encode antilog(log₁₀ x)=x, log_e(x)=ln(x), or log₁₀(10ⁿ)=n.)"
    },
    "CVP-IFACE-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). Success 3/3. Error-path engine·REST·MCP 3/3 (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. Integration: URL → SSR result → Live graph current point (4/4). Hydration/slider/history are URL-canonical contracts, not a live browser session."
    },
    "CVP-ORACLE-01": {
      "result": "PASS",
      "applicability": "higher_assurance",
      "notes": "O3 14/14 tabulated vectors vs IUT · ≤2 ULP vs O3 applies to the 14 published tabulated common-log vectors (log₁₀ of 1, 10, 100, 0.1, 2, 1000 plus 8 seeded random x = 10^(u·6−2) in about [0.01, 10⁴]). It is not a guarantee over all bases, the whole positive reals, or unlisted neighborhoods of 0 and 1.; plus45 independent Decimal200 complete packs:4ULP forward/argument and128ULP solved base, known inputs exact. No whole-domain guarantee."
    },
    "CVP-EXP-01": {
      "result": "SKIP",
      "applicability": "optional",
      "notes": "named expert review not performed"
    }
  },
  "interfaces": {
    "compared": [
      "ui-ssr",
      "rest",
      "mcp",
      "ui-url-result-graph"
    ],
    "result": "PASS",
    "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). Success 3/3. Error-path engine·REST·MCP 3/3 (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. Integration: URL → SSR result → Live graph current point (4/4). Hydration/slider/history are URL-canonical contracts, not a live browser session."
  },
  "artifacts": {
    "evidence_bundle_sha256": "7ea7940b1b316588354bc4b75a1254d09f94288818f1879b5b27056883e8e839",
    "evidence_digest": "a3170216f569b11888ff6098777dfca31877e49e4d0373614a70037558631808",
    "production_sha256": "0904162d9842ae579e660eb678ec02f2ca6e852dd03b716905c0a6501acd7dae",
    "attested_catalog_sha256": "163b0d7072a58bed20a0320572211167e1629730bef43c185b5f545ceac7744c",
    "production_checks": [
      {
        "id": "math.log:output-const",
        "status": "pass",
        "detail": "output const 1.1.6 vs capability 1.1.6",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:evidence-sha256",
        "status": "pass",
        "detail": "1b64590f3d20",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:semantic-contract",
        "status": "pass",
        "detail": "45/45",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:capability-html-public-origin-agree",
        "status": "pass",
        "detail": "public 1.1.6 vs origin 1.1.6",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:cvp-manifest-public-origin-agree",
        "status": "pass",
        "detail": "math.log/1.1.6/2026-10-27.full-review-v3/core/a3170216f569",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z",
        "projection_compared": false
      },
      {
        "id": "math.log:cvp-latest-alias-agrees",
        "status": "pass",
        "detail": "math.log/1.1.6/2026-10-27.full-review-v3/core/a3170216f569",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z",
        "projection_compared": false
      },
      {
        "id": "math.log:cvp-immutable-manifest-fetch",
        "status": "pass",
        "detail": "public=200 origin=200",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:cvp-immutable-manifest-sha256",
        "status": "pass",
        "detail": "a3170216f569",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:cvp-latest-alias-matches-immutable",
        "status": "pass",
        "detail": "math.log/1.1.6/2026-10-27.full-review-v3/core/a3170216f569",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z",
        "projection_compared": false
      },
      {
        "id": "math.log:cvp-reproduce-manifest-agree",
        "status": "pass",
        "detail": "2026-10-27.full-review-v3 · efdad939a92a",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:calculator-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      },
      {
        "id": "math.log:evidence-html-cvp-projection",
        "status": "pass",
        "detail": "matches Trust display",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-10-27T02:19:49.883Z"
      }
    ],
    "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": "a3170216f569b11888ff6098777dfca31877e49e4d0373614a70037558631808",
          "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": "a3170216f569b11888ff6098777dfca31877e49e4d0373614a70037558631808",
          "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": "1b64590f3d2035278452f01abf959cd24b989622fd3faa96d2d720f4a638565f",
          "note": "Published Evidence JSON core — Trust freshness / production bind subject"
        },
        {
          "name": "evidence_catalog_digest",
          "field": "artifacts.attested_catalog_sha256",
          "digest_scope": "capability_catalog",
          "value": "163b0d7072a58bed20a0320572211167e1629730bef43c185b5f545ceac7744c",
          "note": "Capability catalog integrity; site-wide, not per-suite fingerprint"
        }
      ]
    },
    "cvp_core_sha256": "a3170216f569b11888ff6098777dfca31877e49e4d0373614a70037558631808"
  },
  "dependencies": [
    {
      "name": "log-engine",
      "version": "1.1.6"
    },
    {
      "name": "log-reference-oracle",
      "version": "1.0.0"
    },
    {
      "name": "log-o3-mpmath-table",
      "version": "math-mpmath-o3"
    },
    {
      "name": "math.antilog",
      "version": "1.0.7",
      "role": "cross_calculator_peer",
      "capability_id": "math.antilog",
      "evidence_digest": "0100576ce0d393a21f71e88d1b754f9332ebed5d6efb2180e172464a2d3952a8",
      "evidence": "https://www.calculatorx.com/evidence/math.antilog/1.0.7.cvp.json"
    },
    {
      "name": "math.ln",
      "version": "1.0.5",
      "role": "cross_calculator_peer",
      "capability_id": "math.ln",
      "evidence_digest": "49c2f1ec03f3c8e42cca1c3753b6e03431552760fb389946ed82d481b4178d1a",
      "evidence": "https://www.calculatorx.com/evidence/math.ln/1.0.5.cvp.json"
    },
    {
      "name": "math.exponent",
      "version": "1.0.5",
      "role": "cross_calculator_peer",
      "capability_id": "math.exponent",
      "evidence_digest": "fe69527e9020177c3b69cbbc89583c154ca31acc061e4e9f44e9ee2be58239c3",
      "evidence": "https://www.calculatorx.com/evidence/math.exponent/1.0.5.cvp.json"
    },
    {
      "name": "node",
      "version": "22.20.0"
    }
  ],
  "attestation": {
    "status": "CURRENT",
    "href": "/.well-known/calculatorx-production-attestation.json",
    "id": "f3abb5d04ebc51171f259234b69628b210f1534445c968974f68a48041bc5e07",
    "attested_at": "2026-10-27T02:19:49.883Z",
    "last_confirmed_current_at": "2026-10-28T05:11:56.928Z",
    "site_attestation_current": false,
    "capability_attestation_current": true,
    "bound_snapshot_status": "pass",
    "live_report_status": "stale",
    "bound_attested_at": "2026-10-28T05:11:56.928Z",
    "live_updated_at": "2026-10-28T05:12:05.151Z",
    "bound_snapshot": {
      "status": "pass",
      "attested_at": "2026-10-28T05:11:56.928Z",
      "site_stale_count": 16
    },
    "live_site_status": {
      "href": "/.well-known/calculatorx-production-attestation.json"
    },
    "bound_snapshot_site_stale_count": 16,
    "site_stale_capability_count": 16,
    "evidence_attested_at": "2026-10-27T02:19:49.883Z"
  },
  "domain_review": {
    "status": "ABSENT",
    "spec_version": "1.1.6",
    "external_third_party": false,
    "note": "Named expert review not performed"
  },
  "timestamps": {
    "verified_at": "2026-10-27T02:19:49.883Z",
    "generated_at": "2026-10-27T02:19:49.883Z",
    "rendered_at": "2026-10-28T05:12:28.886Z",
    "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": 48,
      "total": 48,
      "failed": 0
    },
    "boundary": {
      "passed": 23,
      "total": 23,
      "failed": 0
    },
    "invalid": {
      "passed": 23,
      "total": 23,
      "failed": 0
    },
    "property": {
      "passed": 2,
      "total": 2,
      "failed": 0
    },
    "round_trip": {
      "passed": 3,
      "total": 3,
      "failed": 0
    },
    "metamorphic": {
      "passed": 2,
      "total": 2,
      "failed": 0
    },
    "contract": {
      "passed": 6,
      "total": 6,
      "failed": 0
    },
    "cross_interface": {
      "passed": 6,
      "total": 6,
      "failed": 0
    },
    "cross_calculator": {
      "passed": 12,
      "total": 12,
      "failed": 0
    },
    "ui_integration": {
      "passed": 4,
      "total": 4,
      "failed": 0
    },
    "o3": {
      "passed": 14,
      "total": 14,
      "failed": 0,
      "claim_scope": "≤2 ULP vs O3 applies to the 14 published tabulated common-log vectors (log₁₀ of 1, 10, 100, 0.1, 2, 1000 plus 8 seeded random x = 10^(u·6−2) in about [0.01, 10⁴]). It is not a guarantee over all bases, the whole positive reals, or unlisted neighborhoods of 0 and 1.; plus45 independent Decimal200 complete packs:4ULP forward/argument and128ULP solved base, known inputs exact. No whole-domain guarantee.",
      "max_error_ulp": 0,
      "table_sha256": "efdad939a92a67df1f3995db36c52bb87f428a59fc73568f789c02540f4372ee"
    }
  },
  "numerical": {
    "representation": "IEEE-754 binary64 change-of-base",
    "tolerance": {
      "type": "ulp",
      "value": 2,
      "rationale": "Independent Math.log change-of-base vs IUT; ≤2 ULP on tabulated O3 common-log vectors, declared a priori. Not a whole-domain or all-bases ULP guarantee.",
      "declared_before_evaluation": true
    },
    "max_error_observed": 0,
    "claim_scope": "≤2 ULP vs O3 applies to the 14 published tabulated common-log vectors (log₁₀ of 1, 10, 100, 0.1, 2, 1000 plus 8 seeded random x = 10^(u·6−2) in about [0.01, 10⁴]). It is not a guarantee over all bases, the whole positive reals, or unlisted neighborhoods of 0 and 1.; plus45 independent Decimal200 complete packs:4ULP forward/argument and128ULP solved base, known inputs exact. No whole-domain guarantee."
  },
  "coverage": {
    "partitions": [
      {
        "id": "log-y",
        "description": "Solve y = log_b(x)",
        "exercised": true,
        "case_count": 69
      },
      {
        "id": "log-x",
        "description": "Solve argument x = b^y",
        "exercised": true,
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