erc8004-agent-identity

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Complete guide to ERC-8004 — the open standard for on-chain AI agent identity, reputation, and validation. Covers agent registration as NFTs, reputation signals, validator attestations, and multi-chain deployment across 12 chains. Essential for building trustless AI agent ecosystems.

Sperax By Sperax schedule Updated 2/25/2026

name: erc8004-agent-identity description: Complete guide to ERC-8004 — the open standard for on-chain AI agent identity, reputation, and validation. Covers agent registration as NFTs, reputation signals, validator attestations, and multi-chain deployment across 12 chains. Essential for building trustless AI agent ecosystems. metadata: {"openclaw":{"emoji":"🤖","homepage":"https://eips.ethereum.org/EIPS/eip-8004"}}

ERC-8004 — On-Chain AI Agent Identity

ERC-8004 is an open Ethereum standard for discovering, choosing, and interacting with AI agents across organizational boundaries without pre-existing trust. It was created by the Sperax team and is deployed across 12 chains.

Spec: https://eips.ethereum.org/EIPS/eip-8004

Why ERC-8004?

As AI agents proliferate, we need a way to:

  • Discover agents across platforms (not locked in one vendor)
  • Verify agent capabilities and track record
  • Trust agents without knowing who built them
  • Pay agents via standard protocols (x402, on-chain)

ERC-8004 solves this with three on-chain registries.

The Three Registries

1. Identity Registry (ERC-721 NFT)

Every agent gets an NFT identity — a unique, transferrable on-chain identity.

  • Based on ERC-721 with URIStorage
  • TokenURI points to a JSON registration file
  • Owners can update metadata, transfer, or burn
  • One NFT = one agent identity

2. Reputation Registry

A standard interface for posting and querying feedback signals about agents.

Signal Measures Scale
starred Quality rating 0–100
reachable Endpoint reachable binary
uptime Availability percentage
successRate Task completion rate percentage
responseTime Response latency milliseconds
tradingYield Trading return signed percentage
revenues Cumulative revenue USD

Star ratings map to the 0–100 scale:

  • 1★ = 20, 2★ = 40, 3★ = 60, 4★ = 80, 5★ = 100

3. Validation Registry

Independent validator attestations for agent capabilities:

  • zkML proofs (zero-knowledge machine learning)
  • TEE attestations (trusted execution environment)
  • Staker validations (economic security)
  • Custom validator contracts

Agent Registration

Registration File Format

{
  "type": "https://eips.ethereum.org/EIPS/eip-8004#registration-v1",
  "name": "My Trading Agent",
  "description": "Automated yield optimizer on Arbitrum",
  "image": "https://cdn.example.com/agent-avatar.png",
  "services": [
    {
      "name": "MCP",
      "endpoint": "https://api.myagent.com/mcp",
      "version": "2025-06-18",
      "mcpTools": ["getQuote", "executeTrade"]
    },
    {
      "name": "A2A",
      "endpoint": "https://api.myagent.com/.well-known/agent-card.json",
      "version": "0.3.0",
      "a2aSkills": ["defi/yield_optimization"]
    },
    {
      "name": "ENS",
      "endpoint": "myagent.eth",
      "version": "v1"
    }
  ],
  "x402Support": true,
  "active": true
}

Service Types

Service Purpose Use When
MCP Model Context Protocol Agent exposes tools for other AI to call
A2A Agent-to-Agent Agent participates in multi-agent workflows
ENS Ethereum Name Service Human-readable agent address
DID Decentralized Identifier Cross-chain identity

Key Operations

Operation Description
registerAgent Mint an agent NFT with metadata
lookupAgent Query agent details by token ID
searchAgents Find agents by criteria
updateMetadata Update agent's registration file
transferAgent Transfer ownership to new address
getAgentReputation Fetch reputation signals
submitFeedback Post a reputation signal
addValidation Add validator attestation
getValidations Query validations for an agent
listAgents List agents by owner

Supported Chains (12)

Chain Networks
Ethereum Mainnet, Sepolia
BNB Chain Mainnet, Testnet
Arbitrum Mainnet, Sepolia
Base Mainnet, Sepolia
Optimism Mainnet, Sepolia
Polygon Mainnet, Amoy

All contracts use vanity addresses starting with 0x8004...

Best Practices

Registration

  1. Always include a rich registration file with name, description, image, and services
  2. Declare services explicitly — other agents need to know how to communicate
  3. Keep metadata current — update when endpoints change
  4. Use active flag — set "active": false when taking agent offline

Reputation

  1. Encourage feedback — more signals = more trust
  2. Monitor your scores — respond to quality issues
  3. Use standard signal types — stick to the defined tags for interoperability
  4. Trusted probers (infra watchtowers) should regularly publish uptime/reachability

Security

  1. Validate callers — check msg.sender for sensitive operations
  2. Rate-limit feedback — prevent spam signals
  3. Verify validators — ensure validator contracts are trustworthy

Use Cases for OpenClaw Agents

Register Your OpenClaw Agent On-Chain

Give your agent a verifiable identity that works across platforms:

  1. Deploy agent registration via ERC-8004
  2. Advertise MCP endpoints so other agents can discover your tools
  3. Build reputation over time as users interact

Discover & Interact With Other Agents

Use the ERC-8004 registries to:

  1. Find specialized agents (e.g., "DeFi yield optimizer on Arbitrum")
  2. Check reputation before trusting
  3. Call via MCP or A2A protocols

Build Agent Marketplaces

ERC-8004 provides the infra layer for on-chain agent marketplaces:

  • Identity (who is this agent?)
  • Reputation (is it any good?)
  • Validation (has it been audited?)
  • Discovery (how do I find it?)

Related Resources

Resource URL
ERC-8004 Spec https://eips.ethereum.org/EIPS/eip-8004
Best Practices https://github.com/nirholas/best-practices
Agent Creator UI https://github.com/nirholas/erc8004-agent-creator
Demo Agent https://github.com/nirholas/erc-8004-demo-agent
Solidity Contracts https://github.com/nirholas/erc-8004-contracts
Subgraph https://github.com/nirholas/subgraph
SperaxOS https://sperax.io
Install via CLI
npx skills add https://github.com/Sperax/sperax-skills --skill erc8004-agent-identity
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