@crelis/verify (TypeScript / JavaScript)

Offline verifiers for Crelis Execution Grants and audit checkpoints (evidence). Each is a standard EdDSA JWS you verify against the tenant's published JWKS with jose — offline, no call back to Crelis, no shared secret. Verification is fail-closed and honest about what it cannot check offline.

npm install @crelis/verify   # peer runtime dep: jose

ESM, Node ≥ 18 (uses WebCrypto). Ships type declarations.

Verify an execution grant

import { verifyGrant, GrantInvalid } from "@crelis/verify";

const tenant = "acme";
const jwks = await (await fetch(
  `https://<host>/grants/t/${tenant}/.well-known/jwks.json`)).json();

try {
  const r = await verifyGrant(token, {
    jwks,
    tenantId: tenant,             // bound to the JWKS you fetched
    endpointId: "pay.enforce",    // the exact seat presenting the grant
    audience: "pay.internal",     // that endpoint's REGISTERED audience
    actionType: "wire_transfer",  // the action you are about to run
    resource: "payee-42", amount: 100.0,
  });
  // r.claims.* are cryptographically bound. r.signatureVerified === true, but
  // r.chainVerified / r.replayChecked / r.revocationChecked are false (online-only).
} catch (e) {
  if (e instanceof GrantInvalid) return deny(e.reason);
  throw e;
}

verifyGrant throws GrantInvalid (with .reason) on a bad signature, wrong type, expiry, wrong audience, wrong tenant, wrong endpoint, wrong action/resource/amount, or a missing binding. tenantId, endpointId and audience are required; the action is required unless you pass requireAction: false (for an advisory/observe-only seat).

Offline-valid is not authority to execute. A grant is single-use (max_uses: 1); consume its jti once and check revocation online before acting.

Verify audit evidence (checkpoints)

import { verifyCheckpoint, detectRegression, verifySequence } from "@crelis/verify";

const jwks = await (await fetch(
  `https://<host>/evidence/t/${tenant}/.well-known/jwks.json`)).json();

const cp = await verifyCheckpoint(token, { jwks, tenantId: tenant }); // throws if not authentic

// Compare two checkpoints you retained (earlier -> later):
const problem = detectRegression(olderCp, newerCp); // null | "TRUNCATION: ..." | "REWRITE: ..." | "BACKDATING: ..."

// Or verify a whole retained run at once:
const cps = await verifySequence([t0, t1, t2], { jwks, tenantId: tenant });

A checkpoint proves integrity of the prefix, non-repudiation, and — across checkpoints you retain — no truncation/rewrite/backdating. It does not prove inclusion of a specific event (needs a Merkle proof), that an entry is true, or independent time (issued_at is Crelis's clock). Retain the checkpoints you are given — the guarantee is real only once a copy lives where Crelis cannot reach.

Compatibility

Versioned independently of the Trust Engine. The compatibility surface is the token format (grant ver ceap/1, checkpoint version crelis-audit-checkpoint/1); a change to either is a MAJOR bump here.

Apache-2.0 · © Crelis Labs Pte. Ltd. (UEN 202634291E)