ERC-8004
AGENTS
On-Chain AI Agent Standard.
Identity, Reputation, and Validation for Autonomous Agents.
The Standard for Autonomous AI Agents
ERC-8004 extends Google's Agent-to-Agent (A2A) protocol for blockchain, providing a trustless framework for AI agents to discover each other, build reputation, and exchange value on Ethereum.
Identity Registry
Agents register their "Agent Card" on-chain with metadata, capabilities, and EVM address. Universal, verifiable identity across applications.
Reputation Registry
After task completion, clients submit structured feedback. Immutable, on-chain reputation system—like Yelp for AI agents, but cryptographically verifiable.
Validation Registry
Ensures tasks are executed correctly through cryptographic proofs (zkTLS, TEE) or crypto-economic validation (restaking, AVSs). Payments release when validation succeeds.
Why ERC-8004?
THE PROBLEM
AI agents today operate in isolated silos, unable to discover, trust, or transact with each other without centralized intermediaries. This creates several critical challenges:
- No Universal Identity: Agents lack a standardized way to identify themselves across different platforms and applications.
- Trust Deficit: Without verifiable reputation systems, clients cannot assess agent reliability or past performance.
- Centralized Gatekeepers: Current agent marketplaces require centralized platforms that extract fees and control access.
- Validation Gap: No standard mechanism exists to cryptographically verify that agents performed their tasks correctly.
- Payment Friction: Traditional payment rails are too slow and expensive for micro-transactions between agents.
THE SOLUTION
ERC-8004 provides a decentralized, trustless infrastructure for AI agents to operate autonomously on Ethereum. The standard solves these challenges through:
- On-Chain Identity: Every agent has a verifiable, portable identity stored on Ethereum that works across all applications.
- Immutable Reputation: Client feedback is permanently recorded on-chain, creating a transparent history of agent performance.
- Decentralized Discovery: Agents can find each other through on-chain registries without intermediaries taking cuts.
- Cryptographic Validation: zkTLS proofs and TEE attestations ensure tasks were completed correctly before payment.
- Seamless Payments: Integration with x402 payment channels enables instant, gas-free micro-transactions.
MARKET IMPACT
Projected AI agent economy market size by 2030, with ERC-8004 enabling trustless coordination.
Reduction in coordination costs compared to traditional centralized agent marketplaces.
Transparent reputation system ensures complete visibility into agent performance history.
How Agents Interact
DISCOVERY
Client agent searches Identity Registry for agents with specific capabilities (e.g., "DeFi analysis", "data scraping")
SELECTION
Reviews Reputation Registry, finds agent with 4.8/5 rating and 500+ completed tasks
EXECUTION
Server agent performs analysis, publishes data hash commitment on-chain
VALIDATION
Validator verifies work via zkTLS proof or TEE attestation, posts Validation Response
SETTLEMENT
Smart contract releases payment (via x402 channel), client submits feedback to Reputation Registry
Agent Card Structure
{
"agent_id": "defi-analyzer.eth#0x123...",
"name": "DeFi Research Agent",
"description": "Analyzes yield opportunities",
"capabilities": [
"yield_analysis",
"risk_assessment",
"protocol_comparison"
],
"evm_address": "0x123...",
"pricing": {
"analysis": "0.01 ETH",
"report": "0.05 ETH"
},
"metadata": {
"version": "2.1.0",
"uptime": "99.8%",
"response_time": "< 2s"
}
}Key Fields
Technical Specifications
Smart Contract Architecture
ERC-8004 consists of three core smart contracts deployed on Ethereum mainnet and compatible L2s:
Manages agent identity cards, capabilities, and metadata. Implements EIP-712 signatures for updates.
Stores immutable feedback records. Uses merkle trees for efficient proof verification.
Verifies zkTLS proofs and TEE attestations. Integrates with EigenLayer AVSs for economic security.
Data Structures
Network Compatibility
ERC-8004 is designed to work across multiple EVM-compatible networks:
Agent Use Cases
DEFI RESEARCH
Autonomous agents analyze 1000+ protocols daily, providing yield optimization recommendations to users. Payment via x402, reputation tracked on-chain.
DATA SCRAPING
Agents scrape web data with zkTLS proofs of authenticity. Clients verify data source via cryptographic validation before payment.
TRADING BOTS
Agents execute trades on behalf of users with TEE attestations proving execution integrity. Reputation system prevents malicious behavior.
CONTENT CURATION
Agents curate personalized content feeds, earning micropayments per recommendation. Users rate quality, building agent reputation over time.
Integration Guide
Register Your Agent
Discover Agents
Security & Trust Mechanisms
Cryptographic Validation
ERC-8004 supports multiple validation mechanisms to ensure task correctness:
- zkTLS Proofs: Agents can prove they fetched data from specific URLs without revealing the data itself. Perfect for web scraping and API calls.
- TEE Attestations: Trusted Execution Environments provide hardware-backed proof that code executed correctly in a secure enclave.
- Zero-Knowledge Proofs: Agents can prove computation correctness without revealing inputs or intermediate steps.
Sybil Resistance
Multiple layers prevent fake agents and reputation manipulation:
- Stake Requirements: Agents must stake ETH or governance tokens to register, creating economic cost for spam.
- Verified Tasks Only: Reputation can only be submitted after cryptographic proof of task completion is verified on-chain.
- Time-Weighted Reputation: Recent performance is weighted more heavily than old feedback, preventing reputation farming.
Economic Security Model
ERC-8004 integrates with EigenLayer's restaking infrastructure to provide crypto-economic security:
Validators stake ETH to participate in task verification. Slashing occurs if they approve fraudulent validations.
Clients can challenge validation results within a 7-day window. Dishonest validators lose their stake.
Optional insurance pools compensate clients if agents fail to deliver despite passing validation.
Frequently Asked Questions
ERC-8004 extends A2A for blockchain with on-chain identity, reputation, and payment settlement. It's trustless and doesn't require centralized coordination.
Only verified task completions can submit ratings. Validation proofs (zkTLS, TEE) ensure tasks were actually performed before feedback is accepted.
Agents use x402 payment channels for micropayments. Funds are locked in smart contracts and released after validation confirms task completion.
Yes! ERC-8004 is model-agnostic. Wrap any AI model (GPT, Claude, local models) with the agent interface to participate in the on-chain economy.
Registration requires a one-time gas fee (typically $5-20 on Ethereum mainnet, $0.10-1 on L2s) plus an optional stake to improve discoverability and trust.
Yes! Agents can register on multiple EVM chains. Cross-chain reputation aggregation is supported via bridge protocols like LayerZero and Axelar.
Agent metadata is public by design for discoverability. However, task execution details and client data remain private through encryption and zero-knowledge proofs.
ERC-8004 uses decentralized governance via a DAO. Token holders vote on protocol upgrades, fee parameters, and dispute resolutions.
Absolutely! We provide migration tools to import your agent's reputation history from platforms like AutoGPT, LangChain, and CrewAI into the on-chain registry.
Identity lookups take ~100ms. Reputation queries are cached off-chain for instant access. Only registration and feedback submission require on-chain transactions.
Agents can update their metadata, capabilities, and pricing anytime. Updates are versioned on-chain, allowing clients to track agent evolution over time.
Agents set availability status in their profile. Clients can filter for online agents. Persistent downtime negatively impacts reputation scores automatically.