{ "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": "1.1.5", "title": "Percent Error Calculator", "formula_family": "percent_error", "capability_id": "math.percent_error", "verification_revision": "2026-10-22.percent-error-complete-contract-v3" }, "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": "22.20.0", "numeric_model": "IEEE-754 binary64", "os": "darwin" }, "suite": { "id": "percent-error", "version": "1.1.5", "uri": "https://www.calculatorx.com/evidence/math.percent_error/1.1.5.json", "verification_revision": "2026-10-22.percent-error-complete-contract-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-DIM-01", "CVP-PROP-01", "CVP-META-01", "CVP-ROUND-01", "CVP-XCAL-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": "All p/o/t directions, absolute/signed and strict-zero8ULP triple consistency; exact binary64-rational arithmetic, complete inverse branches with individual diagnostics, exact infinite endpoints and explicit range/rounding limits" }, "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; 151/151 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 + 33/33 oracle-backed error-code (exact_error_match, not ULP)" }, "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": "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": "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 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=cb614f6316a4a99e61eb83d940f937a7c264e05cb52f3e289bd091d67fdff824 · Capability production binding: STALE · Site report: STALE · Public schema 1.1.5 observed · production binding STALE · Semantic contract ✓ · Last attestation PASS · Evidence changed after the last successful production attestation. Re-attestation required. · Public/cache ✓ · Origin ✓ · schema_const=1.1.5 · 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=7c83e318abf41b280fd1a6c860fa53b512cf36456702de13f93c9f6aaf70ab30 · verified_at=2026-10-22T03:03:11.379Z · evidence_attested_at=2026-10-22T03:03:11.379Z · last_confirmed_current_at=2026-10-22T03:03:11.379Z · rendered_at=2026-10-22T03:38:18.354Z · binds=cvp_core_sha256 · Capability production binding: STALE · Site report: STALE · Evidence changed after the last successful production attestation. Re-attestation required.", "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": "PASS", "applicability": "applicable", "notes": "3/3 cross-calculator · xcal-pe-absolute-change PASS vs math.percent_change; xcal-pe-signed-negative-reference PASS vs math.percent_change; xcal-pe-percentage PASS vs math.percentage; xcal-pe-division-na N/A (General division does not model measurement-reference error or inverse solution sets.)" }, "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 4/4 (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 4/4 (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": "20d6906cfdd2542065c49d0f698374e900e376bd020956c6846c4c79ad1920e9", "evidence_digest": "6f7189188a89c5450fca03a20455d0c885c97f86a2fc1149b913265253166e58", "production_sha256": "7c83e318abf41b280fd1a6c860fa53b512cf36456702de13f93c9f6aaf70ab30", "attested_catalog_sha256": "9b96a2c8fbf62a8306adee80ae161d6b6eeb7d64addac11a3cc4670eb22d2635", "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": "2026-10-22T03:03:11.379Z" }, { "id": "math.percent_error:evidence-sha256", "status": "pass", "detail": "5f08d089bf83", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z" }, { "id": "math.percent_error:semantic-contract", "status": "pass", "detail": "14/14", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z" }, { "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": "2026-10-22T03:03:11.379Z" }, { "id": "math.percent_error:cvp-manifest-public-origin-agree", "status": "pass", "detail": "math.percent_error/1.1.5/2026-10-22.percent-error-complete-contract-v3/engineering/6f7189188a89", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z", "projection_compared": false }, { "id": "math.percent_error:cvp-latest-alias-agrees", "status": "pass", "detail": "math.percent_error/1.1.5/2026-10-22.percent-error-complete-contract-v3/engineering/6f7189188a89", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z", "projection_compared": false }, { "id": "math.percent_error:cvp-immutable-manifest-fetch", "status": "pass", "detail": "public=200 origin=200", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z" }, { "id": "math.percent_error:cvp-immutable-manifest-sha256", "status": "pass", "detail": "630a2997f606", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z" }, { "id": "math.percent_error:cvp-latest-alias-matches-immutable", "status": "pass", "detail": "math.percent_error/1.1.5/2026-10-22.percent-error-complete-contract-v3/engineering/6f7189188a89", "scope": "last_attestation_snapshot", "current": false, "attestation_binding_current": false, "attested_at": "2026-10-22T03:03:11.379Z", "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": "2026-10-22T03:03:11.379Z" }, { "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": "2026-10-22T03:03:11.379Z" }, { "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": "2026-10-22T03:03:11.379Z" } ], "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": "6f7189188a89c5450fca03a20455d0c885c97f86a2fc1149b913265253166e58", "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": "6f7189188a89c5450fca03a20455d0c885c97f86a2fc1149b913265253166e58", "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": "67c53720d73cf33f01dab347216965cd2ff26e42b57bba51d7c8ae21ecebf697", "note": "Published Evidence JSON core — Trust freshness / production bind subject" }, { "name": "evidence_catalog_digest", "field": "artifacts.attested_catalog_sha256", "digest_scope": "capability_catalog", "value": "9b96a2c8fbf62a8306adee80ae161d6b6eeb7d64addac11a3cc4670eb22d2635", "note": "Capability catalog integrity; site-wide, not per-suite fingerprint" } ] }, "cvp_core_sha256": "6f7189188a89c5450fca03a20455d0c885c97f86a2fc1149b913265253166e58" }, "dependencies": [ { "name": "percent-error-engine", "version": "1.1.5" }, { "name": "percent-error-reference-oracle", "version": "1.0.0" }, { "name": "math.percent_change", "version": "1.1.1", "role": "cross_calculator_peer", "capability_id": "math.percent_change", "evidence_digest": "c76f6f160ef881e52b036156937f60dffc0b6681964cfa44d6434a3a88c43f7e", "evidence": "https://www.calculatorx.com/evidence/math.percent_change/1.1.1.cvp.json" }, { "name": "math.percentage", "version": "1.1.2", "role": "cross_calculator_peer", "capability_id": "math.percentage", "evidence_digest": "9cbd3aac385f83b517ed93a52f0ebbf2a360bf18b7ca59a3330a3d91ef27400c", "evidence": "https://www.calculatorx.com/evidence/math.percentage/1.1.2.cvp.json" }, { "name": "node", "version": "22.20.0" } ], "attestation": { "status": "STALE", "href": "/.well-known/calculatorx-production-attestation.json", "id": "cb614f6316a4a99e61eb83d940f937a7c264e05cb52f3e289bd091d67fdff824", "attested_at": "2026-10-22T03:03:11.379Z", "last_confirmed_current_at": "2026-10-22T03:03:11.379Z", "site_attestation_current": false, "capability_attestation_current": false, "bound_snapshot_status": "pass", "live_report_status": "stale", "bound_attested_at": "2026-10-21T08:56:09.611Z", "live_updated_at": "2026-10-22T03:19:04.034Z", "bound_snapshot": { "status": "pass", "attested_at": "2026-10-21T08:56:09.611Z", "site_stale_count": 3 }, "live_site_status": { "href": "/.well-known/calculatorx-production-attestation.json" }, "bound_snapshot_site_stale_count": 3, "site_stale_capability_count": 3, "stale_reason": "Capability production binding: STALE · Site report: STALE · Evidence changed after the last successful production attestation. Re-attestation required.", "evidence_attested_at": "2026-10-22T03:03:11.379Z" }, "domain_review": { "status": "ABSENT", "spec_version": "1.1.5", "external_third_party": false, "note": "Named expert review not performed" }, "timestamps": { "verified_at": "2026-10-22T03:03:11.379Z", "generated_at": "2026-10-22T03:03:11.379Z", "rendered_at": "2026-10-22T03:38:18.354Z", "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": 151, "total": 151, "failed": 0 }, "boundary": { "passed": 4, "total": 4, "failed": 0 }, "invalid": { "passed": 37, "total": 37, "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": 6, "total": 6, "failed": 0 }, "cross_interface": { "passed": 26, "total": 26, "failed": 0 }, "cross_calculator": { "passed": 3, "total": 3, "failed": 0 } }, "numerical": { "representation": "Exact laboratory percent-error formulas of normalized binary64 inputs; one ties-even rounding per field", "tolerance": { "type": "ulp", "value": 0, "rationale": "Independent CPython Fraction/float expected primary, secondary and complete inverse branch set; exact0ULP arithmetic comparison. Separate triple-input consistency uses8ULP same-sign nonzero with strict zero.", "declared_before_evaluation": true }, "max_error_observed": 0, "claim_scope": "Private independent CPython Fraction/float checks complete primary, secondary and inverse branch sets on sampled normalized binary64 inputs; arithmetic comparison0 ULP, triple consistency8 ULP for same-sign nonzero percentages with strict zero. Public disclosure is summary-only, not the private full corpus." }, "coverage": { "partitions": [ { "id": "forward", "description": "Forward |O−T|/|T|×100%", "exercised": true, "case_count": 64 }, { "id": "inverse-observed", "description": "Solve observed O", "exercised": true, "case_count": 52 }, { "id": "inverse-true", "description": "Solve accepted T", "exercised": true, "case_count": 52 }, { "id": "verify", "description": "Three-field verify", "exercised": true, "case_count": 7 }, { "id": "invalid-domain", "description": "Invalid inputs", "exercised": true, "case_count": 37 } ] }, "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": "Independent CPython Fraction complete absolute/signed inverse set", "engine": { "name": "CPython Fraction/float", "precision_bits": 53, "independent_of_iut": true, "same_runtime_as_iut": false } }, { "class": "O2", "reference_scope": "numerical_behavior", "scope": "numerical_behavior", "label": "Independent CPython Fraction complete absolute/signed inverse set", "engine": { "name": "CPython Fraction/float", "precision_bits": 53, "independent_of_iut": true, "same_runtime_as_iut": false } } ] }, "links": { "legacy_evidence": "https://www.calculatorx.com/evidence/math.percent_error/1.1.5.json", "evidence_page": "https://www.calculatorx.com/evidence/math.percent_error/1.1.5", "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/1.1.5.cvp.json", "manifest_immutable": "https://www.calculatorx.com/evidence/math.percent_error/1.1.5/2026-10-22.percent-error-complete-contract-v3.cvp.json", "reproduce": "https://www.calculatorx.com/evidence/math.percent_error/reproduce", "manifest_core": "https://www.calculatorx.com/evidence/math.percent_error/1.1.5/2026-10-22.percent-error-complete-contract-v3.6f7189188a89.cvp.json" }, "disclosure": { "policy": "calculatorx-public-evidence-v1", "full_validation": "private", "representation": "summary" } }