ERC-8004
An Ethereum standard that gives AI agents a verifiable on-chain identity — including a reputation registry and validation registry — so they can be trusted parties in machine-to-machine transactions.
Rail: Payment · Updated: 2026-06-05
What It Is
ERC-8004, formally titled "Trustless Agents," is an Ethereum Improvement Proposal that launched on Ethereum mainnet on January 29, 2026. It establishes a standard for giving AI agents a persistent, verifiable identity on the blockchain — the equivalent of a passport, credit history, and professional certification record for software systems that need to transact with other software systems.
The standard creates three on-chain registries for each agent. The Identity Registry mints a unique ERC-721 non-fungible token for each agent — the same token standard used for digital collectibles, repurposed here as a sovereign identifier. The token resolves to an off-chain metadata file detailing the agent's capabilities, supported protocols, and associated payment wallet. The Reputation Registry acts as an immutable ledger of operational feedback: after an interaction, clients and counterparties log standardized performance scores that build a verifiable track record. The Validation Registry serves high-stakes transactions — agents can request independent verification of their output from third-party validators, ranging from cryptoeconomic stakers to zero-knowledge proof systems, who attest to correctness on-chain.
Together, these registries solve a fundamental problem in machine-to-machine commerce: how does one software system decide whether to trust another? A human can check reviews, call references, or rely on a legal agreement. An AI agent operating autonomously at machine speed needs a trust signal it can verify cryptographically, in milliseconds, without human involvement. ERC-8004's registries provide exactly that. The proposal was authored by Marco De Rossi (MetaMask), Davide Crapis (Ethereum Foundation), Jordan Ellis (Google), and Erik Reppel (Coinbase) — a coalition that drove rapid adoption. Within weeks of launch, over 20,000 agents had registered on Ethereum mainnet. As of June 2026, cross-chain data from 8004scan.io records approximately 234,839 registered agents across 26 blockchain networks.
A note on rail classification: ERC-8004 itself explicitly excludes payment logic and does not grant legal personhood — the specification states that "payment rails are intentionally out-of-scope." MachineEconomy.ai measures ERC-8004 in the Payment Rail, as on-chain identity usage (registry activity) that the payment protocols like x402 depend on. It is not scored in the LRRS legal-identity category: that category covers formal legal frameworks defining machine-readable legal identity, which remain not yet established in any surveyed jurisdiction. The on-chain identity layer, the payment settlement layer (x402), and the legal compliance layer (ERC-8226, a separate standard) are distinct but interdependent components of the full machine economy stack.
Real-World Example
Helixa is a trust and reputation protocol built on ERC-8004. It aggregates raw feedback data from the ERC-8004 Reputation Registry and generates a multi-dimensional score for registered agents. When an AI trading system wants to route capital to a third-party agent for executing a complex data retrieval workflow, it queries Helixa first, checks the agent's on-chain reputation, confirms validation attestations in the ERC-8004 Validation Registry, and only then initiates the workflow. One verifiable identity record, readable by any participant on the network without a centralized authority in the middle.
Related Terms
- Agent Identity — the broader concept ERC-8004 implements
- Agent Wallet — the financial complement to on-chain identity
- x402 Protocol — payment protocol that ERC-8004 agents use with verified identities
- LRRS — the Legal Rail Readiness Score; note ERC-8004 is measured in the Payment Rail, not the LRRS legal-identity category
- Agentic AI — the systems ERC-8004 provides identity for