Offer a post only after Keryx judges its public RSS preview relevant. Once the source is registered, indexed, and ownership-verified, Keryx sponsors one bounded retry with at most $0.05 on Arc Testnet. A payout happens only when the paid full text supplies qualifying evidence, the agent cites it, and Circle settlement succeeds.
Keryx rechecks your registry authority and public preview, then guarantees this version a place in the retry. The agent still decides BUY or SKIP; only grounded, settled evidence fills the claim.
The agent sees your recent titles and summaries — the same free preview a listed source gets judged on. Takes a few seconds.
“What are x402 payments in the context of Keryx, and how are they defined or used?”