Public evidence

engineering.uncertainty.type_b

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON CVP Manifest Reproduce MCP Review policy

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · Type B u_B from half-width a: rectangular a/√3 (uniform alias) and triangular a/√6 + O3 mpmath tabulated u_B.· Single Type B component. Not GUM combination. Not trapezoidal. O3 tabulated vectors only. · Protocol · Schema · Production report

Declared partition coverage: PASS · 6/6 declared partitions (rectangular, triangular, uniform-alias, default-dist, half-width-alias, invalid-domain)
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed · Evidence 2026-09-16.o2-o3
Verification revision: 2026-09-16.o2-o3 · 3/3 property · digest 47360ca02434

Verification

Legacy regression suite: 8/8 calculation tests · Production surface contract 4/4

Three distinct suites: educational examples on the calculator page, this legacy regression count (8/8 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 1.0.0 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 2026-09-16.o2-o3. Calculation version 1.0.0. CVP 1.0.0-proposed. 5/5 golden · 4/4 CVP boundary · 7/7 invalid · 3/3 property · 2/2 metamorphic · 8/8 O3 · 4/4 cross-interface · 4/4 CVP contract. digest 47360ca02434. O2: u_B = a/√3 (rectangular) or a/√6 (triangular) vs separate-module identities (≤2 ULP). Not GUM combination, not trapezoidal, not Monte Carlo. ≤2 ULP vs O3 applies only to the published tabulated Type B vectors (rectangular, triangular, default, uniform alias, a=1, a=0.5 triangular, scale, half_width). It is not a whole-domain Type B guarantee and does not cover trapezoidal.

Golden (oracle-backed) 5 / 5
CVP boundary 4 / 4
Invalid input 7 / 7
Property 3 / 3
Metamorphic 2 / 2
O3 high-precision 8 / 8
Cross-interface 4 / 4
CVP contract 4 / 4
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (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.
Verified scope Type B u_B from half-width a: rectangular a/√3 (uniform alias) and triangular a/√6 + O3 mpmath tabulated u_B.
Assurance Engineering
Deferred Not GUM RSS of several uᵢ, not trapezoidal / U-shaped, not Monte Carlo, and not a standalone Combined/Expanded page.

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

Fingerprint sha256:51e560ba9b2d81d08ccdabec16a4e1a0a63dc4cf2b71f8a03645f95831e11266

Input schema sha256:6080180add3b3e3f6ea07297c66079905ded37d2111f71e63280aff62259290d · Output schema sha256:4173e7a353bcc72cd370af3b7dc7958835fd6bb511d24a743296041b2cc1a277 · 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: type-b
Engine: type-b
Engine build: 2026-09-16
Evidence core: 2026-09-16T21:07:40.795Z
Rendered: 2026-09-16T22:38:08.851Z
Last reviewed: —

Assumptions

Type B: a is the half-width of the assumed distribution
Rectangular (default, including uniform alias) u_B = a/√3; triangular u_B = a/√6
Not GUM combination of several uᵢ
Not Monte Carlo

Limitations

One Type B component from a half-width — not GUM RSS of several uᵢ
Not Monte Carlo
Seeded distributions: rectangular and triangular only

Sources

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

JCGM 100:2008 (GUM) — Evaluation of measurement data — 4.3.7 Rectangular distribution
Supports: If the quantity is modeled as rectangular with half-width a, u = a/√3
JCGM 100:2008 (GUM) — Evaluation of measurement data — 4.3.9 Triangular distribution
Supports: If the quantity is modeled as triangular with half-width a, u = a/√6

Legacy published checks

Golden and boundary cases from the legacy Evidence JSON. CVP property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the Manifest — including SKIP when a suite has no vectors.

ID	Kind	Status	Detail
`golden-type-b`	golden	pass	Expected u_B=1.7320508075688774 · Actual u_B=1.7320508075688774 · a=3 · distribution=rectangular
`boundary-type-b-tri`	boundary	pass	Expected u_B=1.2247448713915892 · Actual u_B=1.2247448713915892 · a=3 · distribution=triangular
`boundary-type-b-missing`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-type-b-a`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-type-b-dist`	boundary	pass	Expected INVALID_INPUT · Actual INVALID_INPUT
`property-rect`	property	pass	a/√3
`property-uniform`	property	pass	uniform=rectangular
`property-tri`	property	pass	a/√6