Public evidence

electrical.watt_volt_amp

Machine-checked verification for calculation version 1.5.1 · tier internally_reviewed

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP status

Resistive DC identities; soft-zero on ÷0

Declared partition coverage: PASS · 4/4 declared partitions (pair-vi, with-power, with-R, invalid-domain)
Versions: Calculation 1.5.1 · CVP protocol 1.0.0-proposed · Evidence 2026-10-28.meta-metrics-v2
Verification revision: 2026-10-28.meta-metrics-v2 · 5/5 property · digest 2f237a4b48b7

Verification

Legacy regression suite: 17/17 calculation tests · Production surface contract 5/5

Three distinct suites: educational examples on the calculator page, this legacy regression count (17/17 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.5.1 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Verification revision 2026-10-28.meta-metrics-v2. Calculation version 1.5.1. CVP 1.0.0-proposed. 4/4 golden · 4/4 CVP boundary · 4/4 invalid · 5/5 property · 2/2 metamorphic · 1/1 cross-interface · 5/5 CVP contract. digest 2f237a4b48b7.

Golden (oracle-backed) 4 / 4
CVP boundary 4 / 4
Invalid input 4 / 4
Property 5 / 5
Metamorphic 2 / 2
Cross-interface 1 / 1
CVP contract 5 / 5
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

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

Fingerprint sha256:23bd4c102728349653307344d5879056aed7badf077c049d9d683bb91babcba1

Input schema sha256:bc49ebb92a15d482954fc73412070f669f8ccacc9667b4ace21e613c8ba12d8e · Output schema sha256:2bff83a1041be8c7a8cffcea93ccc74e7d0d2c8b882a5bfe394dd201b3a0f55a · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: watt-volt-amp
Engine: watt-volt-amp
Engine build: 2026-09-20
Evidence core: 2026-09-20T23:31:21.536Z
Rendered: 2026-11-10T05:18:41.680Z
Last reviewed: 2026-08-08

Assumptions

Ohmic resistance; RMS for AC
First two filled fields define the known pair

Limitations

Resistive model only
Fewer than two inputs throws; zero divisors yield 0 for dependents

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

NIST Guide to the SI (SP 811) — Watt, volt, ampere, and ohm relationships in the SI
Supports: P = V·I; V = I·R; derived forms for P+R pairs
IEC 60050 — International Electrotechnical Vocabulary — Resistance (IEV 131-12-04)
Supports: R = u/I for a resistive two-terminal element; V = I·R and derived P+R forms
IEC 60050 — International Electrotechnical Vocabulary — Active power (IEV 131-11-42)
Supports: P is active power; unit watt (W). For ohmic DC, P = V·I
BIPM SI Brochure (9th edition, version 4.01) — SI units for volt, ampere, ohm, and watt · 2026-06 · DOI
Supports: V, A, Ω, W coherent unit relationships

Verification disclosure

Aggregate outcomes, scope and artifact commitments are public. Complete test inputs, expected values, execution records and oracle infrastructure are retained privately. This summary does not independently reproduce the full verification run.