{"attestation_date":"2026-10-01","merkle_root":"8f3bb56ef98cdee2f6bc7d8686ae6417a81fc70a5a38efc3aceb66bf254899c9","total_sources":42483,"max_source_id":76630,"signature":"4df127586f19ff479e9b8c342a1677165d9d88b48191948c95e2a40efe5bed79","signature_algorithm":"hmac-sha256(date|root|total_sources)","external_publish_url":null,"computed_at":"2026-10-01T02:12:57.393Z","witnesses":[],"verifyHowto":{"summary":"Rebuild the Merkle tree from /source/:id/receipt.json hashes for id in [1..max_source_id] and compare to merkle_root.","leafOrder":"ascending by source.id, content_hash strings as-is (lowercase hex)","hashFunction":"sha256","interiorNodeFormula":"sha256(left_hex || right_hex)","oddLevelHandling":"duplicate the last leaf (Bitcoin convention)"}}