8004 Agent Skill v0.0.1 Register AI agents onchain (ERC-8004) and authenticate them via SIWA (Sign In With Agent) . Overview ERC-8004 ("Trustless Agents") provides three onchain registries deployed as per-chain singletons: - Identity Registry — ERC-721 NFTs. Each agent gets a unique (tokenId) and an pointing to a JSON registration file. - Reputation Registry — Feedback signals (score, tags) from clients to agents. - Validation Registry — Third-party validator attestations (zkML, TEE, staked re-execution). SIWA (Sign In With Agent) is a challenge-response authentication protocol (inspired by S…