PQ Receipt Re-Anchor Tool

Paste an existing AINumbers receipt (any exported Policy Mandate JSON carrying an audit_signature.proof) and countersign it, entirely in this browser tab, with a post-quantum dual signature: SLH-DSA-SHA2-128f (FIPS 205, hash-based, primary) plus ML-DSA-65 (FIPS 204, lattice-based, secondary). The original receipt bytes, digest, and every existing proof are never touched. The tool only appends two new, independent proof-set members.

⚠ This is a local countersignature tool, not a migration, not custody, not a service. The platform never holds, stores, or re-anchors anything on your behalf: every operation is a paste-in, compute, download-out round trip with nothing retained after the tab closes. There is no key escrow, and no recovery path if the exported key is lost, by design.

FIPS 205 · SLH-DSA FIPS 204 · ML-DSA Zero PII Client-Side · Zero-Storage

Scope & reliance: 🔒 All inputs are processed locally in your browser. No data is transmitted. Do not enter real personal data, use synthetic or anonymised inputs only. Key generation, signing, and hashing all happen in this tab; nothing is written to sessionStorage, localStorage, or IndexedDB. Deterministic logic · no inference · zero PII · CC BY 4.0.

Are AINumbers receipts quantum-safe? The honest three-tier answer

1.Hash-binding: yes. SHA-256, used throughout for canonicalization and digesting, has no known quantum break that threatens preimage or collision resistance at current parameter sizes. Grover's algorithm only halves the effective security margin, which SHA-256 already absorbs.

2.The Groth16 seal: no. Any zkVM-sealed receipt's proof rests on a BN254 pairing and a trusted setup, both broken by a sufficiently large quantum computer via Shor's algorithm against the underlying elliptic-curve discrete-log problem. This tool does not touch, re-seal, or claim to fix that layer.

3.This tool's mitigation: the artifact layer only. The appended PQ signatures add a second, independent, post-quantum-resistant attestation of the artifact, alongside the seal. They do not, and cannot, make the seal itself quantum-safe. "Quantum-safe receipts" as an unqualified claim is never accurate; the mitigation is layered, not total.

Step 1: Paste receipt

Step 2: Generate ephemeral countersigning keys

No recovery. Keys are generated in memory only, for this tab, this session. Export both secret keys below before you countersign: refresh or close the tab and they are gone forever. A PQ countersignature is only as durable as your own key handling; the tool makes no other claim.

Step 3: Countersign & download