@metamynd/magp-trust — offline Trust Index verifier

Zero-dependency verifier for a MetaMynd Trust Index record. A published record is independently checkable with no call to MetaMynd:

1. Re-derive the score from the record's own adapter breakdown — the same deterministic HCS-28 weighted mean the issuer ran (weights travel in the record) — and confirm it matches the claimed score / denominator.
2. Verify the Ed25519 proof against MetaMynd's known issuer key.

Both must pass. Uses only Node ≥ 18 built-ins.

Use

import { verifyTrustRecord } from "@metamynd/magp-trust";

// record = the object from GET /api/v1/trust-index/:did (or an HCS-28 topic message)
const r = verifyTrustRecord(record, { publicKey: METAMYND_ISSUER_KEY_HEX });
// → { ok, scoreOk, signatureOk, derived: { score, denominator, coverage }, reasonCode }

Pin publicKey to MetaMynd's known issuer key (from GET /trust-index/:did → issuerKey, or the policy pubkey endpoint) for real trust — otherwise the record's self-claimed key is used (convenience only). reDeriveTrustScore(record) returns just the recomputed { score, denominator, coverage }.

CLI

node magp-trust.mjs record.json [issuerPublicKeyHex]   # exit 0 = VERIFIED, 1 = failed

How records are published

MetaMynd anchors the signed record to an HCS-28 Agent Transparency topic (POST /api/v1/trust-index/:did/publish, owner/admin). Fetch it from the Hedera mirror node and run it through this verifier — the score is tamper-evident (re-derivation) and the issuer is authenticated (signature), with MetaMynd offline.

See docs/design/metamynd-trust-index.md for the scoring model and adapter catalog.