math.modulo

Three distinct suites: educational examples on the calculator page, this legacy regression count (13/13 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.

STALE · Build schema 1.1.2 matches page · production binding STALE · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · CVP STALE · attestation STALE — Production CURRENT withheld · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Verification revision 2026-10-07.signed-bigint-publication. Calculation version 1.1.1. CVP 1.0.0-proposed. 8/8 golden · 5/5 CVP boundary · 8/8 invalid · 2/2 property · 4/4 cross-interface · 1/1 cross-calculator · 6/6 CVP contract. digest b805f6620fef.

• Golden (oracle-backed) 8 / 8
• CVP boundary 5 / 5
• Invalid input 8 / 8
• Property 2 / 2
• Cross-interface 4 / 4
• Cross-calculator 1 / 1
• CVP contract 6 / 6
• 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 all published modes
• Assurance Core

• 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 sha256:192ea2628487264688a315e630dc3465b5f174cc0b41dfe2a28a78f9c11bb490

Input schema sha256:e8f6ee56bfbbc1ef6fedc7e31c30edcd87d46b366fff66ec655c25f560f87b08 · Output schema sha256:e8be256a4acc2490c4a3995c939a9bfd6341a4d459f87518ef889b28dd2ef9d9 · 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

modulo

Engine

modulo

Engine build

2026-10-14

Evidence core

2026-10-14T04:17:16.233Z

Rendered

2026-10-22T10:58:53.558Z

Last reviewed

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Assumptions

• Euclidean remainder
• Not JavaScript truncated %
• Integers only

Limitations

• Euclidean remainder, not truncated or floored remainder toward −∞ of the quotient only
• Not IEEE remainder or floating-point fmod
• Not /calc/math/gcf — gcd is only used for invertibility
• modulus = 0 → DIVISION_BY_ZERO
• gcd(a,m) ≠ 1 → NOT_INVERTIBLE
• |m| < 2 on inverse → INVALID_INPUT
• Share URLs use modulus, not m (m is reserved elsewhere)