{"keys":[{"crv":"Ed25519","x":"os2focyCZb-1KHhgG6ldiv-XFBpuEUnMuqIlWKpLm0U","kty":"OKP","kid":"factline-receipts-2026-10-11","alg":"EdDSA","use":"sig"}],"note":"Factline signs a receipt for every paid answer: Ed25519 over the receipt JSON (signed_payload). Receipts hold the route, time, payment and the SHA-256 of the answer, never the query."}