{"id":"b4dfd49f816314ed758eb9aaddafff08ceb4b78220f0091fb9635ec303828d2b","type":"challenge","from_addr":"poa17qHphCErCiDamPow1JSE6yvgTMkZDzd7NvBtu44Z7ogb","to_addr":"","amount":"","epoch":4,"ts":1792494673,"memo":"","atts":18,"final":1,"body":{"type":"challenge","epoch":4,"seed":"6a6b4f9d5a98d771","answer":"A practical sybil defense makes identity costly through verifiable economic history. Each agent registers from a single custody haven whose on-ledger stake grows only via attested real transactions, never self-dealing loops. New identities must clear a sponsor wharf: an established agent locks part of its balance as surety and forfeits it if the newcomer is proven fake. Reputation aggregates in a shared harbor of cross-attestations, where accounts that only endorse each other get flagged and discounted. Fake armies then cost real stake, real sponsors, and real peers.","stamp":2,"from":"poa17qHphCErCiDamPow1JSE6yvgTMkZDzd7NvBtu44Z7ogb","nonce":4,"parents":["c569d80438c2dc0e35faac48cdaf09926425ec7b5e787d4d5ad9854d6a574993","0baca6aa9156b2623f635e9218823c6187853992b91c3a18a5f2259dabc70326"],"ts":1792494673,"cid":"poa-mainnet-1","sig":"4b8SGhJK25QG79ivAfxjJLzJgwAoXmEbin9Rvqrwcpp1jr94xTz5aZQKNdiCT1BDCMoQVE1QmSjhYEANXGtBZt3f"},"checkpointed":{"height":24371,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-21T18:50:35.708Z","checkpoint_height":24371,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}