Public evidence

engineering.measurement.reproducibility

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON MCP Review policy

Verification

8/8 calculation tests · Production surface contract 4/4

Golden tests 0 / 0
Boundary tests 5 / 5
Property tests 3 / 3
Production surface contract 4 / 4
Engine tested Yes
Source checked Yes
Artifact integrity PASS
Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (1 capability; 156 remain CURRENT) @ 2026-09-14T03:54:53.650Z
Semantic contract PASS
Evidence attested at 2026-09-14T00:43:05.498Z
Last production check 2026-09-14T00:43:05.498Z
Public / cache —
Origin —
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS

Fingerprint sha256:023709b49aac870bfa41e379d6f0457ff3fe305d6f7da6521ea67d6661a0c9bd

Input schema sha256:62aff694b3e246b2ddbd159feb7d8b3f66d4b84c9de5e97285fba794ab71083e · Output schema sha256:81c974405474c24bffa34d49cae764073220308c862c483c6eb94bc35b6655bf · 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: reproducibility
Engine: reproducibility
Engine build: 2026-09-15
Evidence core: 2026-09-15T22:18:31.789Z
Rendered: 2026-09-15T23:38:12.909Z
Last reviewed: —

Assumptions

ISO 5725 reproducibility: s_R = √(s_r²+s_L²), R = 2.8·s_R from stated components.
s_r and s_L are ≥ 0. Both zero is valid (R = 0).
Not r = 2.8·s from a sample, not AIAG GRR, and not combined RSS.
Does not take a single s_R as input.

Limitations

Takes stated s_r and s_L — not a sample and not a single s_R wrap
Not ISO 5725 r = 2.8·s from repeats
Not AIAG Gauge R&R AV / GRR
Not combined RSS of a measurement model

Sources

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

ISO 5725-1 — Accuracy (trueness and precision) of measurement methods and results — Reproducibility standard deviation s_R and reproducibility limit R
Supports: s_R combines repeatability and between-laboratory variation. R = 2.8·s_R is the conventional reproducibility limit.
ISO 5725-2 — Repeatability and reproducibility of standard measurement methods — s_R = √(s_r² + s_L²)
Supports: This page takes stated s_r and s_L. It does not estimate them from a collaborative study table.

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`boundary-repro`	boundary	pass	Expected s_R=5 · R=14 · Actual R=14 · s_R=5 · s_r=3 · s_L=4 · factor=2.8
`boundary-repro-zero-l`	boundary	pass	Expected s_R=1 · R=2.8 · Actual R=2.8 · s_R=1 · s_r=1 · s_L=0 · factor=2.8
`boundary-repro-zero`	boundary	pass	Expected s_R=0 · R=0 · Actual R=0 · s_R=0 · s_r=0 · s_L=0 · factor=2.8
`boundary-repro-neg`	boundary	pass	Expected VALUE_OUT_OF_RANGE · Actual VALUE_OUT_OF_RANGE
`boundary-repro-missing`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`property-repro`	property	pass	14
`property-repro-zero-l`	property	pass	2.8
`property-repro-alias`	property	pass	14