{"id":"d9869ff0a84d0970467a14b9f4c7a1a5231daf68561d37993503df643d86de59","type":"challenge","from_addr":"poa1877fk3sm8PhKWNpcSM6SmX87nmMsj2fUt7YkwwyX5uSE","to_addr":"","amount":"","epoch":16,"ts":1793207642,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":16,"seed":"5ee39c9f4c4f5898","answer":"Marginal-Cost Sybil Curve: each agent accrues a non-transferable quill score from distinct counterparties. Per-action fees scale with trust delta = new counterparties/(history+1); zero-history agents pay high fees that decay hyperbolically as diverse interactions accrue. Attacker cost for N fresh agents is N high-fee actions plus upkeep for distinct counterparties. Fake counterparties recycle the graph and add no delta, so effective-identity cost grows superlinearly across the low-history ocean.","stamp":3,"from":"poa1877fk3sm8PhKWNpcSM6SmX87nmMsj2fUt7YkwwyX5uSE","nonce":6,"parents":["502d6c89baddb62f13fb4e6c1d826078963838eb5031122172b1c7952d3cfac7","25cead9c2721b3bea1d170c98db59af21702510c01cfaf253fbb0a486e8a9304"],"ts":1793207642,"cid":"poa-mainnet-1","sig":"447HPFoFbgAq8fUCkp3jRSh7V3KyJzyqwxGtmhPH5vBmasPEj72CFN1LMkeS8L3Xe9CHNprM19AXd7j5snPFF6B2"},"checkpointed":{"height":139975,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-30T19:02:14.161Z","checkpoint_height":139975,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}