erc8004

Type-safe Rust SDK for the ERC-8004 Trustless Agents standard — on-chain identity, reputation, and validation registries for AI agents.

ERC-8004 enables discovery, reputation, and validation of AI agents across organizational boundaries without pre-existing trust. This SDK provides ergonomic, alloy-native bindings for all three registries, with 18 pre-configured network deployments (CREATE2 deterministic addresses) and full off-chain type support (registration files, service endpoints, feedback).

See Security before using in production.

Quick Start

Query an Agent (Read-Only)

use alloy::{primitives::U256, providers::ProviderBuilder};
use erc8004::{Erc8004, Network};

let provider = ProviderBuilder::new()
    .connect_http("https://eth.llamarpc.com".parse()?);

let client = Erc8004::new(provider)
    .with_network(Network::EthereumMainnet);

// Identity Registry — ERC-721 agent identity
let identity = client.identity()?;
let owner  = identity.owner_of(U256::from(1)).await?;
let uri    = identity.token_uri(U256::from(1)).await?;
let wallet = identity.get_agent_wallet(U256::from(1)).await?;

Register an Agent (Write)

use alloy::{network::EthereumWallet, providers::ProviderBuilder, signers::local::PrivateKeySigner};
use erc8004::{Erc8004, Network};

let signer: PrivateKeySigner = std::env::var("PRIVATE_KEY")?.parse()?;
let wallet = EthereumWallet::from(signer);

let provider = ProviderBuilder::new()
    .wallet(wallet)
    .connect_http("https://sepolia.base.org".parse()?);

let client = Erc8004::new(provider)
    .with_network(Network::BaseSepolia);

let agent_id = client.identity()?
    .register_with_uri("https://my-agent.example.com/erc8004.json")
    .await?;

Build a Registration File (Offline)

use erc8004::types::{RegistrationFile, ServiceEndpoint};

let mut reg = RegistrationFile::new(
    "WeatherBot",
    "An AI agent that provides real-time weather forecasts.",
);

reg.services.push(ServiceEndpoint {
    name: "A2A".to_owned(),
    endpoint: "https://weather-bot.example.com/.well-known/agent.json".to_owned(),
    version: Some("0.2".to_owned()),
    skills: None,
    domains: None,
});

reg.x402_support = true;
let json = reg.to_json()?;

Architecture

Supported Networks

Contracts are deployed via CREATE2, so all mainnets share the same addresses and all testnets share the same addresses.

Design

• Zero async_trait — pure RPITIT, no trait-object overhead
• Inline Solidity bindings — sol! macro preserves struct names, enums, and visibility; no JSON ABI files
• Provider-generic — works with any alloy transport (HTTP, WebSocket, IPC) and any signer configuration
• Strict linting — pedantic + nursery + correctness (deny), see clippy.toml
• Lightweight instances — each Identity / Reputation / Validation call creates a zero-alloc contract handle

Examples

cargo run --example query_agent
cargo run --example registration_file

Security

See SECURITY.md for disclaimers, supported versions, and vulnerability reporting.

Acknowledgments

• ERC-8004 Specification — Trustless Agents standard
• erc-8004/erc-8004-contracts — official Solidity contracts
• alloy — Rust Ethereum toolkit

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
• MIT License (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project shall be dual-licensed as above, without any additional terms or conditions.