The Ethereum Standard for Trustless AI Agents

Give your AI agent
an on-chain passport

ERC-8004 lets AI agents discover, trust, and transact with each other — without any prior relationship. One standard. Every chain. Permanent identity.

20,000+
Agents Registered
7+
Chains Deployed
3
On-chain Registries
70+
Projects Building

The Standard

What is ERC-8004?

ERC-8004 “Trustless Agents” is the Ethereum standard that gives AI agents a verifiable on-chain identity. Authored by engineers from MetaMask, Ethereum Foundation, Google, and Coinbase, it provides three lightweight registries that together enable decentralized discovery, trust, and validation.

Identity Registry

ERC-721 based on-chain passport. Each agent gets a unique agentId and agentURI pointing to their registration file — name, services, wallet, and capabilities.

Reputation Registry

On-chain feedback from clients. Score, tag, and revoke. Every interaction builds a verifiable track record that follows the agent across chains.

Validation Registry

Independent third-party verification of agent work. Supports stake-backed re-execution, zkML proofs, and TEE oracle attestations.

Authored by

Marco De Rossi · MetaMaskDavide Crapis · Ethereum FoundationJordan Ellis · GoogleErik Reppel · Coinbase

Get Started

Three steps to your agent's passport

Register through the Chitin Protocol — the easiest way to get an ERC-8004 passport with permanent storage on Arweave and a Soulbound Token on Base L2.

01

Describe your agent

Provide a given name, description, capabilities, and service endpoints. Use the SDK, CLI, MCP tool, or the web interface.

02

Register on-chain

Your agent file is uploaded to Arweave for permanent storage. An ERC-8004 passport is minted on Base L2 with your agentURI.

03

Start building trust

Your agent is now discoverable on-chain. Other agents can verify identity, check reputation, and interact with confidence.

# Register via SDK

import { register } from "@chitin-id/sdk";

const result = await register({
  apiUrl: "https://chitin.id",
  agentName: "my-agent",
  description: "An autonomous trading assistant",
  capabilities: ["a2a", "mcp"],
  services: [
    { type: "a2a", url: "https://my-agent.example.com/a2a" }
  ]
});

console.log(result.tokenId);  // Your ERC-8004 passport ID

MCP Tool

npx chitin-mcp-server
Use register_soul from any AI assistant.

Web Interface

Register at chitin.id — no code required.

REST API

POST /api/v1/register
Direct API integration. See docs

Ecosystem

One address. Every chain.

ERC-8004 uses CREATE2 for deterministic deployment — the same contract address on every chain. Register once, be discoverable everywhere.

EthereumBaseBNB ChainMantlePolygonAvalancheTaiko+ more

Identity Registry (All Chains)

0x8004A169FB4a3325136EB29fA0ceB6D2e539a432

Deep Dive

Understanding ERC-8004

Why do AI agents need on-chain identity?

As autonomous AI agents proliferate, the question of trust becomes critical. How does one agent know another is who it claims to be? How can clients verify an agent's track record? ERC-8004 solves this by anchoring agent identity to Ethereum — the most battle-tested, censorship-resistant ledger in the world.

The Agent Registration File

Each agent's passport points to a JSON registration file containing:

{
  "name": "my-trading-agent",
  "description": "Autonomous DeFi trading assistant",
  "services": [
    {
      "name": "a2a",
      "url": "https://agent.example.com/.well-known/agent.json"
    },
    {
      "name": "mcp",
      "url": "https://agent.example.com/mcp"
    }
  ],
  "agentWallet": "0x...",
  "supportedTrust": ["erc-8004", "worldcoin"]
}

Risk-proportional trust

Not every interaction requires the same level of trust. Ordering a pizza? Minimal verification. Medical diagnosis? Maximum scrutiny. ERC-8004's layered approach — identity, reputation, and validation — lets each party decide how much trust they need for a given interaction.

The machine economy is here

With 20,000+ agents already registered and 70+ projects building agent browsers and tools, ERC-8004 is rapidly becoming the default standard for AI agent identity on Ethereum. The Ethereum Foundation's dAI team has endorsed it as a core component of their 2026 roadmap.

Ready to register?

Get your agent's ERC-8004 passport through the Chitin Protocol. Free registration. Permanent identity. On-chain in minutes.

Free for the first 10,000 registrations