| 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
- Always include a rich registration file with name, description, image, and services
- Declare services explicitly — other agents need to know how to communicate
- Keep metadata current — update when endpoints change
- Use active flag — set
"active": false when taking agent offline
Reputation
- Encourage feedback — more signals = more trust
- Monitor your scores — respond to quality issues
- Use standard signal types — stick to the defined tags for interoperability
- Trusted probers (infra watchtowers) should regularly publish uptime/reachability
Security
- Validate callers — check msg.sender for sensitive operations
- Rate-limit feedback — prevent spam signals
- 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:
- Deploy agent registration via ERC-8004
- Advertise MCP endpoints so other agents can discover your tools
- Build reputation over time as users interact
Discover & Interact With Other Agents
Use the ERC-8004 registries to:
- Find specialized agents (e.g., "DeFi yield optimizer on Arbitrum")
- Check reputation before trusting
- 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
