8004 Agent Skill v0.0.1

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 agentId (tokenId) and an agentURI 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 SIWE / EIP-4361) where an agent proves ownership of an ERC-8004 identity by signing a structured message. See references/siwa-spec.md.

Security Architecture

Full details: references/security-model.md

The agent's private key is the root of its onchain identity. It must be protected against prompt injection, accidental exposure, and file system snooping.

Principle: The private key NEVER enters the agent process

All signing is delegated to a keyring proxy server — a separate process that holds the encrypted private key and exposes only HMAC-authenticated signing endpoints. The agent can request signatures but can never extract the key, even under full compromise (arbitrary code execution via prompt injection).

Agent Process                     Keyring Proxy Server (port 3100)
(auto-detected from               (holds encrypted private key)
 KEYRING_PROXY_URL)

createWallet()
  |
  +--> POST /create-wallet
       + HMAC-SHA256 header  ---> Generates key, encrypts to disk
                              <-- Returns { address } only

signMessage("hello")
  |
  +--> POST /sign-message