engineering.process.guard_band

Three distinct suites: educational examples on the calculator page, this legacy regression count (6/6 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 · 3/3 CVP boundary · 6/6 invalid · 3/3 property · 2/2 metamorphic · 8/8 O3 · 4/4 cross-interface · 4/4 CVP contract. digest f0b6360d0f41. O2: GB=k·u and optional acceptance limits vs separate-module identities (≤2 ULP). Not ILAC G8 risk, not Cp/Cpk, not Monte Carlo. ≤2 ULP vs O3 applies only to the published tabulated GB vectors (default k, explicit k, two-sided, USL-only, LSL-only, u=0). It is not a whole-domain guarantee and does not cover ILAC G8 risk or Cp/Cpk.

• Golden (oracle-backed) 5 / 5
• CVP boundary 3 / 3
• Invalid input 6 / 6
• 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 Simple guard band GB=k·u (k default 2) and optional A_USL/A_LSL + O3 mpmath tabulated GB.
• Assurance Engineering
• Deferred Not ILAC G8 / JCGM 106 consumer-producer risk tables, not Cp/Cpk, not Monte Carlo, and not a standalone Combined/Expanded page.

• 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

Fingerprint sha256:627fa63547b70bd89e84e6f4a2ae64a4b4dc7fff3f9b3f3a97a08fae1d502165

Input schema sha256:016985412089204a0464c005ecf8a90ab1f7340907f5e294be02e2fd7209d30b · Output schema sha256:727853f8a26875295a768f3fbe8b1edcfbe471c65d73674a6453d9d1d510d7f6 · 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.

Tool

guard-band

Engine

guard-band

Engine build

2026-09-16

Evidence core

2026-09-16T05:06:07.111Z

Rendered

2026-11-10T05:18:41.777Z

Last reviewed

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Assumptions

• GB = k·u with k default 2
• Not ILAC G8 / JCGM 106 risk-based decision rules
• USL and LSL optional; omitted limits skip that acceptance output
• Not Cp/Cpk and not Monte Carlo

Limitations

• GB = k·u with k default 2 — not ILAC G8 / JCGM 106 risk-based rules
• USL and LSL optional; omitted limits skip that acceptance output
• Not Cp/Cpk and not Monte Carlo