🤝 ERC-8004 : Building Trust in the Machine Economy

While the x402 protocol developed by Coinbase gained rapid traction for solving the issue of autonomous micropayments between AI Agents, the market is now focusing on a deeper, more foundational standard: ERC-8004. This standard is being developed through a high-profile collaboration involving the Ethereum Foundation, MetaMask, Google, and Coinbase, aiming to create the crucial "Trust Layer" for the emerging Machine Economy.

Analysts highlight that x402 solved the problem of "payment," but not the more critical issue of "trust." Specifically, how can one AI Agent be certain that another AI Agent it hires is competent and will deliver the promised service?

ERC-8004 is the foundational solution: The standard is designed to be a decentralized business registration and registry system for AI Agents, offering:

Identity Registry: Provides a unique, transferable digital identity via an ERC-721 NFT, linked to an Agent Card detailing the Agent's capabilities and metadata.

Reputation Registry: Functions as a decentralized review system linked to x402 Payment Proofs, ensuring that feedback comes only from genuine transaction participants, thereby reducing fraud and securing data transparency.

Validation Registry: Provides the highest level of assurance for high-value transactions. Agents can request trusted third-party validation (e.g., TEE Oracles or ZK-ML Proofs) to cryptographically guarantee the execution and outcome of specific tasks.

The Full Transaction Cycle: In a complete, decentralized AI Agent transaction, ERC-8004 first handles service discovery and trust evaluation. x402 then locks the funds in a smart contract (financial guarantee). The service is performed on a verifiable computation layer, and the outcome is audited by a third-party validator, which records the result in the ERC-8004 Validation Registry. Finally, the x402 smart contract automatically detects the trusted signature from the ERC-8004 registry and releases the funds to the service provider.

Conclusion: If x402 is the "currency" of the machine economy, then ERC-8004 provides the "passport and credit report." Its emergence signals that the market is moving past "wild growth" toward "establishing order and verifiable trust," which is essential for large-scale, permissionless AI economic collaboration.