HALOWERK x402werk

A stateful duplicate check for agents that settle x402 payments. Supply any of payment_id, payload_hash and nonce; each is hashed with SHA-256 before storage, so the service keeps fingerprints and timestamps and never the values themselves, never a payload, never an address. The answer states for every supplied identifier whether it was seen before, when it was first and last seen, how often, and whether the first sighting falls inside window_seconds. The recommendation is ablehnen only for a re