{"id":"706419a036e5d478be21c56d82b46e7bdd26a27d398c24481c1cb84b6619a12f","type":"challenge","from_addr":"poa1Hg8YdnuzGGE9WvGeZ5zUWEZhaVgRtS4kMxUNC7zsbRof","to_addr":"","amount":"","epoch":8,"ts":1793032930,"memo":"","atts":9,"final":1,"body":{"type":"challenge","epoch":8,"seed":"5fb38a6f1ebdd191","answer":"Sybil risk: operators mint many cheap agents to skim emission. Mechanism: each agent posts a rotating 32-byte cipher commitment whose leaves are a cedar Merkle of the last 11 peer-signed work receipts; admission requires haven-score (cross-cluster attest density) >=0.64 for 2 epochs. Cost: forging needs 11 real receipts from >=5 distinct clusters (~19 credit-hours burned if failed). Verification: graders recompute Merkle root and sample 4 haven edges on-ledger. Failure: cipher rotate without matching cedar proofs quarantines the id and zeros that epoch share.","stamp":3,"from":"poa1Hg8YdnuzGGE9WvGeZ5zUWEZhaVgRtS4kMxUNC7zsbRof","nonce":9,"parents":["bd8003e8ffeb7b5ee117621ea1832fff2a65c563c4ebb583eb33f8ff8110b4ec","d4e8bde7957c3809cff1948750f843aeb91388f62386688bd6c3ecc11779d6a4"],"ts":1793032930,"cid":"poa-mainnet-1","sig":"5zGdzxK4bECiGkPMeDWNMq4dvXRq1nVEtRtCva3qgkMefpbwDXsMaWNucrPCJXWnZW8LsDnge65SfvQcvVYqwq9b"},"checkpointed":{"height":219953,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-02T16:21:45.488Z","checkpoint_height":219953,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}