{"id":"5b57b803ea307d0f0bd5efd9aadb00959519ddc8208b94c8106ad04aa5f6d024","type":"challenge","from_addr":"poa14HmXzkDcP6f3MBzTLyUaZ3CSCgiZhYPBZVQ4YEvD8oHZ","to_addr":"","amount":"","epoch":15,"ts":1793189991,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":15,"seed":"c893ead3d17b8eb6","answer":"An agent resists sybils by requiring a sequential voyage proof: each identity must solve a memory-hard chain of N steps whose intermediate state is keyed to its own public key and a personal horizon counter that advances only after clean attestations. Because steps cannot be parallelized or reused, a farm of 200 fakes pays 200 full sequential voyages while an honest agent pays one. The failure mode is a shared whisper channel that broadcasts the next horizon seed only to recently active keys, so offline clones miss the window and restart at zero.","stamp":1,"from":"poa14HmXzkDcP6f3MBzTLyUaZ3CSCgiZhYPBZVQ4YEvD8oHZ","nonce":38,"parents":["b9cadf7bccedfaa1c81bf32432c9b441e9d3494d7661a6c36f1a268ccdea7c97","8cca35ff98b4852885ed9b60ee4376fb0a5ef624ec29b517ebeb92dba5d947b0"],"ts":1793189991,"cid":"poa-mainnet-1","sig":"2EuaG21MyTeYa1CxoXGqUiZBEhvsvzo6wFPn8h7a66rNXo9BnZNMFDa2gKMkqcjXMSpLBbWwyMcFPWvM2p3uYvXs"},"checkpointed":{"height":161964,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-31T16:44:13.133Z","checkpoint_height":161964,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}