Author: Lacie Zhang, Bitget Wallet Researcher
I. Introduction: From the heated discussion surrounding x402 to the debut of ERC-8004
Recently, the x402 protocol, designed specifically for automated micropayments between AI agents, has become a hot topic in the market, with discussions about its early potential rife. However, beneath the spotlight of x402, a more fundamental standard—ERC-8004—is quietly entering the view of astute observers.
A new question arises: since x402 is already focused on solving payment problems, what is the positioning of ERC-8004? Are the two in competition?
The answer seems to be no. They are more like a pair of ingeniously designed, complementary components in the business landscape of AI agents.
Source: Davide Crapis's X post, Lead AI at the Ethereum Foundation
One noteworthy detail is that Erik Reppel, the creator of x402 from Coinbase, is also one of the final signatories of the ERC-8004 protocol. He was joined by key representatives from MetaMask, Google, and the Ethereum Foundation. This heavyweight lineup and high degree of overlap strongly suggest that the two are not in competition, but rather working together to build a larger blueprint.
The logic behind this blueprint is quite clear: if the emergence of x402 validated the huge demand for AI-assisted payments, then ERC-8004 represents another fundamental core element necessary for building this vast machine economy. It targets precisely the core problem that x402 cannot solve alone—where does trust come from in an economy where AI agents collaborate autonomously? Bitget Wallet Research Institute may help you find the answer in this article.
II. The "Trust" Problem in Agent Collaboration: A Dilemma That x402 Cannot Solve Alone
In business collaborations between AI agents, payment (the problem solved by x402) is merely the final step in the closed loop. A more fundamental question arises: how can an AI agent be certain that another AI agent it employs is trustworthy? In other words, how can an agent prove its ability to complete the assigned task?
To answer this question, we need to explore the fundamental framework of intelligent agent commerce. According to the theory supported by Davide Crapis of the Ethereum Foundation, a decentralized AI intelligent agent commerce system must rely on three pillars to operate stably: discovery, communication, and computation.
Source: Davide Crapis retweeted X's tweet
As can be seen from the table above, the x402 protocol primarily addresses the payment standard issue within the communication layer, but it fails to resolve crucial authentication and reputation assessments. Before making a payment, the AI agent first needs to be securely "discovered" to establish trust and collaboration—ERC-8004 addresses this problem by building a decentralized trust layer.
ERC-8004, spearheaded by the Ethereum Foundation's dAI team and Consensys, in collaboration with MetaMask, Google, Coinbase, and other organizations, aims to serve as an on-chain "trust layer" for AI agents. It is a decentralized business registration and licensing system—providing each AI agent with a verifiable identity, complete historical performance, and proof of capability. All information is immutably recorded on the blockchain and publicly accessible to all participants.
Source: ERC-8004 official website
III. ERC-8004: Decentralized Trust Layer for Intelligent Agents
ERC-8004 is positioned as the underlying infrastructure of the intelligent agent economy. Its core value lies in solving the fundamental problem of the lack of trusted identities among AI intelligent agents through blockchain technology, enabling them to break free from the constraints of traditional centralized platforms and establish verifiable, cross-platform collaborative relationships.
The operation of this mechanism begins with the input of trusted data by ecosystem contributors: AI developers are responsible for registering the unique identity of the intelligent agent; application developers continuously provide behavioral feedback of the intelligent agent to accumulate reputation data; and the verification service acts as an independent auditor to provide credible on-chain verification of the intelligent agent's operational results.
Source: Compiled by Bitget Wallet
This information is collectively fed into the ERC-8004 registry center, which integrates the protocol's three core functions:
- Identity Registry: It assigns a unique digital identity to each AI agent via the ERC-721 NFT protocol. This design not only makes the identity transferable but also allows it to be linked to a standardized "Agent Card" to record the agent's name, capabilities, and metadata in detail, ultimately enabling permissionless discovery across platforms.
- Reputation Registry: This mechanism acts as a decentralized vetting system based on identity registration. Customers or other agents can submit structured feedback. Its key design feature is that these reviews are linked to x402 payment proofs, ensuring that only genuine transaction participants can conduct assessments, effectively reducing fraud and guaranteeing the transparency of all reputation data.
- The Validation Registry provides ultimate assurance for high-risk or high-value transactions. Agents can request trusted verification from third parties, such as TEE oracles, staked inference, or zero-knowledge machine learning proofs (ZK-ML proofs). These verification methods provide cryptographic proofs for specific model execution and outputs, thus establishing a verifiable accountability mechanism similar to professional certification in traditional markets.
Built upon the trusted data foundation provided by ERC-8004, a completely new ecosystem of downstream applications has flourished. This includes explorers for agent discovery and querying, marketplaces that allow agents to trade freely based on reputation, professional rating agencies, and even innovative services such as InfoFi and AgentFi. These advanced applications are all built upon the trusted identities and verification records of agents, marking the formal establishment of a permissionless, highly collaborative agent service ecosystem.
IV. Collaborative Operation: The Complete Process of a Smart Agent Transaction
So how do these components work together in practice? The complete lifecycle of a decentralized AI agent transaction can clearly illustrate this process.
Source: Compiled by Bitget Wallet
- First, the demand-side agent uses the ERC-8004 identity and reputation registry to perform service discovery and evaluation, querying and filtering service providers with specific capabilities and good credit.
- After both parties reach an agreement, the requesting party then locks the required fees in a smart contract (i.e., financial security) through the x402 payment agreement.
- Subsequently, the service provider's agent begins to execute tasks and accept third-party verification. The results of their work are run on a verifiable computing layer such as EigenCompute and generate cryptographic proofs. Then, an independent third-party verification agent records the audit results in the ERC-8004 verification registry.
- Finally, the automatic settlement process begins. The x402 smart contract automatically detects the trusted signature in the ERC-8004 verification registry. Once the task is confirmed to be successful, the funds will be automatically released to the service provider's agent.
In this closed-loop process, ERC-8004 is responsible for access and acceptance, x402 is responsible for payment, and verifiable computation ensures the process; all three are indispensable. This also indicates that, unlike x402, whose early benefits are concentrated in payment tokens, the ERC-8004 ecosystem (as shown in the diagram below) will be distributed across multiple layers, including infrastructure, middleware, and applications.
Source: BlockFlow
V. Conclusion: The Order and Future of the Machine Economy
It must be acknowledged that ERC-8004 is still in the early stages of promotion and implementation—the cold start of related products and whether its grand vision of encompassing "machine-based economic identity verification" can be realized remain to be seen. Furthermore, the cost and specific implementation path of third-party verification, as well as its interoperability with protocols such as x402, are all significant variables that need to be addressed in the future.
What is certain, however, is that the emergence of protocols like ERC-8004 signifies a shift in the machine economy from "wild growth" to "establishing order." For the first time, it provides a cross-platform identity and credit system for autonomous AI agents.
If x402 is the "currency" of the machine economy, then ERC-8004 provides the "passport" and "credit report," marking the beginning of a permissionless, highly collaborative, and trustworthy intelligent agent service ecosystem.
