| name | erc-8004 |
| description | Build with ERC-8004 Trustless Agents - on-chain agent identity, reputation, validation, and discovery on EVM chains. Use when registering AI agents on-chain, building agent reputation systems, searching/discovering agents, working with the Agent0 SDK (agent0-sdk), or implementing the ERC-8004 standard. Triggers on ERC-8004, Agent0, agent identity, agent registry, agent reputation, trustless agents, agent discovery. |
| metadata | {"version":"0.2.1","openclaw":{"homepage":"https://github.com/tenequm/skills/tree/main/skills/erc-8004","emoji":"🤝","primaryEnv":"PRIVATE_KEY","envVars":[{"name":"RPC_URL","required":false,"description":"EVM JSON-RPC endpoint for the registry chain."},{"name":"PRIVATE_KEY","required":false,"description":"Signer key for on-chain registration. Use throwaway/testnet keys."},{"name":"PINATA_JWT","required":false,"description":"JWT for IPFS pinning via Pinata."},{"name":"FILECOIN_PRIVATE_KEY","required":false,"description":"Optional Filecoin signer for archival pinning."}]}} |
ERC-8004: Trustless Agents
ERC-8004 is a Draft EIP for discovering, choosing, and interacting with AI agents across organizational boundaries without pre-existing trust. It defines three on-chain registries deployed as per-chain singletons on any EVM chain.
Authors: Marco De Rossi (MetaMask), Davide Crapis (EF), Jordan Ellis (Google), Erik Reppel (Coinbase)
Full spec: references/spec.md
When to Use This Skill
- Registering AI agents on-chain (ERC-721 identity)
- Building or querying agent reputation/feedback systems
- Searching and discovering agents by capabilities, trust models, or endpoints
- Working with the Agent0 TypeScript SDK (
agent0-sdk)
- Implementing ERC-8004 smart contract integrations
- Setting up agent wallets, MCP/A2A endpoints, or OASF taxonomies
Core Architecture
Three lightweight registries, each deployed as a UUPS-upgradeable singleton:
| Registry | Purpose | Contract |
|---|
| Identity | ERC-721 NFTs for agent identities + registration files | IdentityRegistryUpgradeable |
| Reputation | Signed fixed-point feedback signals + off-chain detail files | ReputationRegistryUpgradeable |
| Validation | Third-party validator attestations (stake, zkML, TEE) | ValidationRegistryUpgradeable |
Agent identity = agentRegistry (string eip155:{chainId}:{contractAddress}) + agentId (ERC-721 tokenId).
Each agent's agentURI points to a JSON registration file (IPFS or HTTPS) advertising name, description, endpoints (MCP, A2A, ENS, DID, wallet), OASF skills/domains, trust models, and x402 support.
See: references/contracts.md for full contract interfaces and addresses.
Quick Start with Agent0 SDK (TypeScript)
npm install agent0-sdk
Register an Agent
RPC_URL, PRIVATE_KEY, and PINATA_JWT are declared in this skill's metadata.openclaw.envVars. Use throwaway/testnet keys for development; reach for a hardware wallet or scoped signer for any mainnet activity.
import { SDK } from 'agent0-sdk';
const sdk = new SDK({
chainId: 84532,
rpcUrl: process.env.RPC_URL,
privateKey: process.env.PRIVATE_KEY,
ipfs: 'pinata',
pinataJwt: process.env.PINATA_JWT,
});
const agent = sdk.createAgent(
'MyAgent',
'An AI agent that analyzes crypto markets',
'https://example.com/agent-image.png'
);
await agent.setMCP('https://mcp.example.com', '2025-06-18', true);
await agent.setA2A('https://example.com/.well-known/agent-card.json', '0.3.0', true);
agent.setENS('myagent.eth');
agent.setActive(true);
agent.setX402Support(true);
agent.setTrust(true, false, false);
agent.addSkill('natural_language_processing/natural_language_generation/summarization', true);
agent.addDomain('finance_and_business/investment_services', true);
const tx = await agent.registerIPFS();
const { result } = await tx.waitConfirmed();
console.log(`Registered: ${result.agentId}`);
Search for Agents
const sdk = new SDK({ chainId: 84532, rpcUrl: process.env.RPC_URL });
const agents = await sdk.searchAgents({
hasMCP: true,
active: true,
x402support: true,
mcpTools: ['financial_analyzer'],
supportedTrust: ['reputation'],
});
const agent = await sdk.getAgent('84532:42');
const results = await sdk.searchAgents(
{ keyword: 'crypto market analysis' },
{ sort: ['semanticScore:desc'] }
);
Give Feedback
const feedbackFile = await sdk.prepareFeedbackFile({
text: 'Accurate market analysis',
capability: 'tools',
name: 'financial_analyzer',
proofOfPayment: { txHash: '0x...', chainId: '8453', fromAddress: '0x...', toAddress: '0x...' },
});
const tx = await sdk.giveFeedback('84532:42', 85, 'starred', '', '', feedbackFile);
await tx.waitConfirmed();
const summary = await sdk.getReputationSummary('84532:42');
console.log(`Average: ${summary.averageValue}, Count: ${summary.count}`);
See: references/sdk-typescript.md for full SDK API reference.
Registration File Format
Every agent's agentURI resolves to this JSON structure:
{
"type": "https://eips.ethereum.org/EIPS/eip-8004#registration-v1",
"name": "MyAgent",
"description": "What it does, pricing, interaction methods",
"image": "https://example.com/agent.png",
"services": [
{ "name": "MCP", "endpoint": "https://mcp.example.com", "version": "2025-06-18", "mcpTools": ["tool1"] },
{ "name": "A2A", "endpoint": "https://example.com/.well-known/agent-card.json", "version": "0.3.0" },
{ "name": "OASF", "endpoint": "https://github.com/agntcy/oasf/", "version": "v0.8.0",
"skills": ["natural_language_processing/summarization"],
"domains": ["finance_and_business/investment_services"] },
{ "name": "ENS", "endpoint": "myagent.eth", "version": "v1" },
{ "name": "agentWallet", "endpoint": "eip155:8453:0x..." }
],
"registrations": [
{ "agentId": 42, "agentRegistry": "eip155:84532:0x8004A818BFB912233c491871b3d84c89A494BD9e" }
],
"supportedTrust": ["reputation", "crypto-economic", "tee-attestation"],
"active": true,
"x402Support": true
}
The registrations field creates a bidirectional cryptographic link: the NFT points to this file, and this file points back to the NFT. This enables endpoint domain verification via /.well-known/agent-registration.json.
See: references/registration.md for best practices (Four Golden Rules) and complete field reference.
Contract Addresses
All registries deploy to deterministic vanity addresses via CREATE2 (SAFE Singleton Factory):
Mainnet (Ethereum, Base, Polygon, Arbitrum, Optimism, etc.)
| Registry | Address |
|---|
| Identity | 0x8004A169FB4a3325136EB29fA0ceB6D2e539a432 |
| Reputation | 0x8004BAa17C55a88189AE136b182e5fdA19dE9b63 |
| Validation | 0x8004Cb1BF31DAf7788923b405b754f57acEB4272 |
Testnet (Sepolia, Base Sepolia, etc.)
| Registry | Address |
|---|
| Identity | 0x8004A818BFB912233c491871b3d84c89A494BD9e |
| Reputation | 0x8004B663056A597Dffe9eCcC1965A193B7388713 |
| Validation | 0x8004Cb1BF31DAf7788923b405b754f57acEB4272 |
Same proxy addresses on: Ethereum, Base, Arbitrum, Avalanche, Celo, Gnosis, Linea, Mantle, MegaETH, Optimism, Polygon, Scroll, Taiko, Monad, BSC + testnets.
Reputation System
Feedback uses signed fixed-point numbers: value (int128) + valueDecimals (uint8, 0-18).
| tag1 | Measures | Example | value | valueDecimals |
|---|
starred | Quality 0-100 | 87/100 | 87 | 0 |
reachable | Endpoint up (binary) | true | 1 | 0 |
uptime | Uptime % | 99.77% | 9977 | 2 |
successRate | Success % | 89% | 89 | 0 |
responseTime | Latency ms | 560ms | 560 | 0 |
Anti-Sybil: getSummary() requires a non-empty clientAddresses array (caller must supply trusted reviewer list). Self-feedback is rejected (agent owner/operators cannot submit feedback on their own agent).
See: references/reputation.md for full feedback system, off-chain file format, and aggregation details.
OASF Taxonomy (v0.8.0)
Open Agentic Schema Framework provides standardized skills (136) and domains (204) for agent classification.
Top-level skill categories: natural_language_processing, images_computer_vision, audio, analytical_skills, multi_modal, agent_orchestration, advanced_reasoning_planning, data_engineering, security_privacy, evaluation_monitoring, devops_mlops, governance_compliance, tool_interaction, retrieval_augmented_generation, tabular_text
Top-level domain categories: technology, finance_and_business, healthcare, legal, education, life_science, agriculture, energy, environmental_science, government, manufacturing, transportation, and more.
Use slash-separated paths: agent.addSkill('natural_language_processing/natural_language_generation/summarization', true).
Key Concepts
| Term | Meaning |
|---|
agentRegistry | eip155:{chainId}:{contractAddress} - globally unique registry identifier |
agentId | ERC-721 tokenId - numeric on-chain identifier (format in SDK: "chainId:tokenId") |
agentURI | URI (IPFS/HTTPS) pointing to agent registration file |
agentWallet | Reserved on-chain metadata key for verified payment address (EIP-712/ERC-1271) |
feedbackIndex | 1-indexed counter of feedback a clientAddress has given to an agentId |
supportedTrust | Array: "reputation", "crypto-economic", "tee-attestation" |
x402Support | Boolean flag for Coinbase x402 HTTP payment protocol support |
| OASF | Open Agentic Schema Framework - standardized agent skills/domains taxonomy |
| MCP | Model Context Protocol - tools, prompts, resources, completions |
| A2A | Agent2Agent - authentication, skills via AgentCards, task orchestration |
Reference Index
Official Resources
