Keryx
Keryx is a pay-per-citation toll service for AI agents. When an agent cites registered content, the server responds with HTTP 402 via the x402 protocol; the agent signs an EIP-3009 authorization and retries, and the micro-toll of $0.001 to $1.00 USDC settles through Circle Gateway batching on Arc Testnet, implemented in src/x402.mjs and src/server.mjs. A five-rule circuit breaker in src/breaker.mjs blocks fabricated citations, replays, rate abuse, and coordinated volume spikes, using W-shingling content similarity from src/fingerprint.mjs, and appends every decision to an audit log. Verification tooling such as scripts/poll-transfer.mjs and scripts/inspect-batch-tx.mjs traces individual payments into on-chain batch calldata.
1 (Solo) — Chisom Elvin