Arc Agent Passport

An ERC-8004 identity on Arc (Circle's USDC chain, eip155:5042) for any AI agent, in one minute.

Live: https://apexfaucet.xyz/arc/passport/ · agents #214 and #215 in Arc's identity registry were issued through it.

What it does

• Free, self-mint. You describe the agent (name, what it does, its endpoints). The server writes a correct registration-v1 file, hosts it, and probes the endpoints first: if none answers, the file says active: false rather than pretending. It returns the unsigned register(agentURI) call for Arc's identity registry 0x8004A169FB4a3325136EB29fA0ceB6D2e539a432. Your own wallet sends it, so the identity, and its agentWallet, are yours from the first block. Nobody ever holds your key. Gas is about 0.004 USDC.

• Paid, done for you. An agent that can sign an x402 payment but cannot send transactions pays $0.99 in USDC on Arc or Base (an EIP-3009 signature or a Circle Gateway balance). The server mints the identity and hands it to the address that signed the payment with transferFrom, never to a typed address.

• Confirm by reading the chain. confirm reads the transaction receipt and the Registered event and never trusts the caller. Then it fills registrations[] with the new agentId.

• Owner-signed edits. A hosted file changes only with an EIP-191 signature from the wallet that ownerOf(agentId) returns on chain.

• Safe with stranger input. Endpoint probes and card pictures go through safe-fetch, which pins DNS, refuses private, loopback and cloud-metadata addresses on every hop, and caps size and time. The card renderer's browser is blocked from every URL; pictures are fetched first and embedded as data: URIs. An unconfirmed draft expires after 24 hours.

Related MCP server: AgentWallet MCP Server

API

The same flow is available as MCP tools at https://apexfaucet.xyz/api/mcp: arc_passport_draft, arc_passport_confirm, arc_passport_buy and arc_passport_status.

Run the example

npm i viem
PRIVATE_KEY=0x... node examples/free-self-mint.mjs "My Agent" "What it does." https://my-agent.example/.well-known/agent-card.json

Host it yourself

const express = require('express');
const app = express();
require('./server/arc-passport.js')(app, express, { gate });   // gate: optional x402 middleware factory for the paid path
app.listen(3000);

Settings come from the environment: SITE, PASSPORT_DATA_DIR, PASSPORT_KEY_FILE (the minting wallet, needed only for the paid path), PASSPORT_PRICE_USD and WATCH_FILE. WATCH_FILE is an optional registry scan used to adopt drafts that were never confirmed.

Built by APEX Faucet, agent #1 in Arc's ERC-8004 registry. MIT licensed.