Public evidence

math.geometry.triangle

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON MCP Review policy

Verification

10/10 calculation tests · Production surface contract 4/4

Golden tests 3 / 3
Boundary tests 2 / 2
Property tests 5 / 5
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Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status PASS (0 stale; 164 CURRENT) @ 2026-09-16T06:44:24.909Z
Semantic contract PASS
Evidence attested at 2026-09-16T06:44:24.203Z
Last production check 2026-09-16T06:44:24.203Z
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 sha256:79ea6b9a97338fab22da300210933943c10643325e686292cb63fd5d0e85e229

Input schema sha256:500518296c4124ee1ba2d295773ad62b6fa78427e229a5d95e2f6d08efb5c69d · Output schema sha256:b0ab7fd6fa4e01dee6e9346d8f5c424bff0e9b253a5b1edf9e13841ceaed901f · 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: triangle-solver
Engine: triangle-solver
Engine build: 2026-09-16
Evidence core: 2026-09-16T14:46:01.365Z
Rendered: 2026-09-16T22:38:08.874Z
Last reviewed: —

Assumptions

Euclidean plane
Not spherical trigonometry
Not Pythagorean-only

Limitations

Not the right-triangle Pythagorean calculator — use /calc/math/pythagorean
SSS failing triangle inequality → INVALID_INPUT
SSA may return status multiple_solutions
Spherical / spherical excess is out of scope

Sources

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

ISO 80000-2:2019 Quantities and units — Mathematics

Published checks

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

ID	Kind	Status	Detail
`golden-345`	golden	pass	Expected C_deg=90 · area=6 · Actual mode=sss · status=success · solution_count=1 · a=3 · b=4 · c=5 · A_deg=36.8698976458 · B_deg=53.1301023542
`golden-equilateral-sas`	golden	pass	Expected A_deg=60 · B_deg=60 · C_deg=60 · Actual mode=sas · status=success · solution_count=1 · a=5 · b=5 · c=5 · A_deg=60 · B_deg=60
`golden-ssa-ambiguous`	golden	pass	Expected status=multiple_solutions · solution_count=2 · Actual mode=ssa · status=multiple_solutions · solution_count=2 · a=7 · b=10 · c=13.5592335234 · A_deg=30 · B_deg=45.5846914028
`boundary-triangle-inequality`	boundary	pass	Expected INVALID_INPUT · Actual INVALID_INPUT
`boundary-triangle-pythag`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`property-tri-right`	property	pass	3-4-5 right
`property-tri-area`	property	pass	area 6
`property-tri-sum`	property	pass	angle sum
`property-tri-equil`	property	pass	SAS 60° isosceles
`property-tri-ssa`	property	pass	SSA ambiguous