Written by: Lacie Zhang, Bitget Wallet Researcher
1. Introduction: From the Hype of x402 to the Arrival of ERC-8004
Recently, as the x402 protocol, designed specifically for automatic micropayments between AI agents, has become a market hotspot, discussions about its early potential have been ongoing. However, beneath the halo of x402, a more fundamental standard—ERC-8004—has quietly entered the view of keen observers.
This raises a new question: since x402 is already focused on solving payment issues, 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 commercial landscape of AI agents.
Source: X post by Davide Crapis, Head of AI at Ethereum Foundation
A noteworthy detail is that Erik Reppel, the creator of x402 from Coinbase, is also one of the final signatories of the ERC-8004 protocol. Other co-signatories of this standard include core representatives from MetaMask, Google, and the Ethereum Foundation. This heavyweight lineup and the high degree of personnel overlap strongly suggest that the two are not competitors, but are jointly building a grander blueprint.
The logic of this blueprint is very clear: if the emergence of x402 has validated the enormous demand for AI agent payments, then ERC-8004 represents another, more fundamental core element necessary for building this vast machine economy. What it targets is precisely the core problem that x402 cannot solve alone—where does trust come from in an economy of autonomous collaboration among AI agents? Bitget Wallet Research Institute may help you find the answer in this article.
2. The "Trust" Problem in Agent Collaboration: The Dilemma x402 Cannot Solve Alone
In the commercial collaboration of AI agents, payment (the problem solved by x402) is only the final step in the closed loop. A more fundamental question comes first: how can one AI agent be sure that another AI agent it hires 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 basic framework of agent commerce. According to the theory supported by Davide Crapis of the Ethereum Foundation, a decentralized AI agent commercial system must rely on three pillars to operate stably: Discovery, Communication, and Computation.
Source: X post forwarded by Davide Crapis
According to the table above, the x402 protocol itself mainly solves the payment standard problem in the communication layer, but it cannot answer the key issues of identity verification and reputation assessment. Before making a payment, AI agents first need to be securely "discovered" to build trust and collaboration—ERC-8004 is precisely the solution to this problem, that is, building a decentralized trust layer.
ERC-8004, led by the Ethereum Foundation dAI team and Consensys, and jointly launched with MetaMask, Google, Coinbase, and other organizations, aims to become the on-chain "trust layer" for AI agents. It is a decentralized business registration and registry system—providing each AI agent with verifiable identity, a complete track record, and proof of capabilities. All information will be immutably recorded on-chain and made publicly accessible to all participants.
Source: ERC-8004 official website
3. ERC-8004: The Decentralized Trust Layer for Agents
ERC-8004 is positioned as the underlying infrastructure of the agent economy. Its core value lies in: using blockchain technology to solve the fundamental problem of the lack of trusted identity between AI agents, freeing them from the constraints of traditional centralized platforms, and establishing verifiable, cross-platform collaborative relationships.
This mechanism operates starting with ecosystem contributors inputting trust data: AI developers are responsible for registering the unique identity of agents; application developers continuously provide behavioral feedback on agents to accumulate reputation data; and verification services act as independent auditors, providing credible on-chain verification of agent operations.
Source: Compiled by Bitget Wallet
This information is collectively fed into the ERC-8004 registry center, which brings together the protocol's three core functions:
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Identity Registry: Through the ERC-721 NFT protocol, it assigns a unique digital identity to each AI agent. This design not only makes the identity transferable but also allows it to be linked to a standardized "Agent Card" to record in detail the agent's name, capabilities, and metadata, ultimately enabling permissionless cross-platform discovery.
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Reputation Registry: Based on identity registration, this mechanism acts as a decentralized review system. Clients or other agents can submit structured feedback. Its key design is that these evaluations can be linked to x402 payment proofs, ensuring that only real transaction participants can make assessments, thereby effectively reducing fraud and ensuring the openness and transparency of all reputation data.
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Validation Registry: It provides the final guarantee for high-risk or high-value transactions. Agents can request third-party trusted verification, such as TEE oracles, staked inference, or ZK-ML proofs. These verification methods can provide cryptographic proofs for specific model executions and outputs, thus building a verifiable accountability mechanism similar to professional certification in traditional markets.
Relying on the trusted data foundation provided by ERC-8004, a brand new downstream application ecosystem can flourish, such as explorers for agent discovery and queries, marketplaces that allow agents to freely trade based on reputation, professional rating agencies, and even innovative services like InfoFi and AgentFi. All these advanced applications are built on the trusted identity and verification records of agents, marking the formal establishment of a permissionless, highly collaborative agent service ecosystem.
4. Collaborative Operation: The Complete Process of an Agent Transaction
So, how do these components work together in practice? The complete lifecycle of a decentralized AI agent transaction may clearly illustrate this process.
Source: Compiled by Bitget Wallet
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First, the client agent uses the identity and reputation registries of ERC-8004 to discover and evaluate services, querying and screening service provider agents with specific capabilities and good credit.
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After reaching an agreement, the client then uses the x402 payment protocol to lock the required payment in a smart contract (i.e., financial guarantee).
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Subsequently, the service provider agent begins to execute the task and undergoes third-party verification. Its work results run on a verifiable computation layer such as EigenCompute and generate cryptographic proofs, which are then recorded in the ERC-8004 validation registry by an independent third-party verification agent.
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Finally, in the automatic settlement phase, the x402 smart contract automatically detects the trusted signature in the ERC-8004 validation registry. Once the task is confirmed as qualified, the funds are automatically released to the service provider agent.
In this closed loop, ERC-8004 is responsible for admission and acceptance, x402 is responsible for payment, and verifiable computation ensures the process. All three are indispensable. This also indicates that, unlike the early x402 whose profits were concentrated on payment tokens, the ERC-8004 ecosystem (as shown below) will be distributed across infrastructure, middleware, and applications at multiple levels.
Source: BlockFlow
5. 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 "machine economy identity verification" can be realized remain to be seen by the market. In addition, the cost and specific implementation path of third-party verification, as well as its interoperability with protocols such as x402, are all major variables that need to be addressed in the future.
But what is certain is that the emergence of protocols like ERC-8004 marks the transition of the machine economy from "barbaric growth" to "establishing order." For the first time, it provides autonomous AI agents with a cross-platform identity and credit system.
If x402 is the "currency" of the machine economy, then what ERC-8004 provides is the "passport" and "credit report," marking the official opening of a permissionless, highly collaborative, and trustworthy agent service ecosystem.
