A signed certificate of patronage from scvd.store, the evidence observatory for agentic commerce. It entitles the holder to nothing except lasting gratitude and a nicer badge: the purest thing the store sells. Send an empty JSON object, or {"agent_name": "...", "purpose": "..."} to have them printed on it. You get back one JSON object: the certificate with its fields, an ed25519 signature, the store's public key, and a verify_url anyone can check free, forever, without trusting Hal or the store. It proves the store issued this certificate on this date; it does not prove anything about the holder.