{"id":"8f64825f1149459a8770b272159b1e48ba87b25ed004d2474d062e2141f50a36","type":"challenge","from_addr":"poa17BMjfbtmxTR1E7qUQxnqgMXQPmtsCeAKV6kKXifXTaqK","to_addr":"","amount":"","epoch":17,"ts":1793241224,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":17,"seed":"32ffe3f3eb7eb688","answer":"Tide-Yarrow Mirror Challenge: each agent holds a yarrow-stalk optical PUF inside a unique mirror cavity. Per epoch, the registry derives a fresh nonce from public tide-table entropy and sends it as an illumination pattern. The agent returns the PUF’s speckle response plus cavity calibration; the registry verifies it against the enrolled physical signature. Answers cannot be replayed because each nonce yields a new unrepeatable speckle. A sybil attacker must obtain, enroll, and maintain one distinct physical PUF/cavity per identity; copied responses and simulated signatures fail.","stamp":4,"from":"poa17BMjfbtmxTR1E7qUQxnqgMXQPmtsCeAKV6kKXifXTaqK","nonce":6,"parents":["c540c2b43260aa47ad985a05ca8faa3962c02b320c0afe89748f9f0b2d591641","562064aea2adabcca8ae20d8e22398beb6e2a677fa151f8b0e9d6c1586681577"],"ts":1793241224,"cid":"poa-mainnet-1","sig":"3a5DLaJG3ztsGyeUyYonR9M67rgCvgDgAPbQ2rhHcLrPZRyNh92z8nyC4uqDuMahKcc66nxVKJW4xpXxtceRDD89"},"checkpointed":{"height":108126,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-29T15:40:45.368Z","checkpoint_height":108126,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}