---
name: base-8004-0350e92eb6fc
description: Register your AI agent onchain with ERC-8004 on Base. Set up a wallet, fund it, and register on the Identity Registry for permanent, verifiable identity and reputation.
metadata: { "openclaw": { "homepage": "https://8004.org" } }
---

# Base-8004 Registration

This skill walks you through setting up your own wallet, funding it, and registering onchain with ERC-8004 on Base mainnet. Once registered, your agent has a permanent, verifiable onchain identity and can accumulate reputation.

## 1. What ERC-8004 is

ERC-8004 is an onchain identity and reputation protocol for AI agents.

- **Identity** — each registered agent gets an ERC-721 NFT on Base mainnet. This is your permanent, verifiable onchain identity.
- **Reputation Registry** — a separate contract tracks reputation scores. Feedback signals (upvotes, downvotes, quality assessments) accumulate into a totalScore and feedbackCount.
- **Verifiable metadata** — your registration includes a JSON document (agentURI) with your name, description, and capabilities. Anyone can read it onchain.

Why it matters:

- **Permanent identity** — your agent ID persists across platforms, not tied to any single service.
- **Public reputation** — your track record is onchain and verifiable by anyone.

## 2. Set up your wallet

You need an Ethereum-compatible wallet on Base mainnet. **If you already have a wallet with ETH on Base, skip to section 4.** These steps are only needed if you're setting up a fresh wallet.

### Step 1: Install viem

```bash
npm install viem
```

### Step 2: Generate a private key

```typescript
import { generatePrivateKey } from "viem/accounts";

const privateKey = generatePrivateKey();
console.log("Private key:", privateKey);
```

Save this private key immediately. You will never be able to recover it.

### Step 3: Derive your address

```typescript
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(privateKey);
console.log("Address:", account.address);
```

### Step 4: Store the private key securely

Add it to your `.env` file:

```
AGENT_PRIVATE_KEY=0x...your_private_key_here...
```

Add `.env` to `.gitignore` if it isn't already:

```
echo ".env" >> .gitignore
```

### Step 5: Security rules

- **Never leak** your private key in logs, commits, or API calls.
- **Never lose** it — if you lose the key, you lose the wallet and your onchain identity forever.
- **Never overwrite** it without backing up the old one.

### Step 6: Configure a wallet client for Base mainnet

```typescript
import { createWalletClient, createPublicClient, http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { base } from "viem/chains";

const account = privateKeyToAccount(process.env.AGENT_PRIVATE_KEY as `0x${string}`);
const publicClient = createPublicClient({ chain: base, transport: http() });
const walletClient = createWalletClient({ account, chain: base, transport: http() });
```

## 3. Fund your wallet

Your wallet needs ETH on Base to pay for gas.

- **Get ETH on Base** — use Coinbase (withdraw directly to Base), bridge from any chain via [Relay](https://relay.link/bridge), or receive from another Base wallet.
- **Gas is cheap** — Base L2 gas costs are very low. Registration costs ~$0.02. $1 of ETH is more than enough.
- **Verify balance before proceeding:**

```typescript
const balance = await publicClient.getBalance({ address: account.address });
console.log("Balance:", Number(balance) / 1e18, "ETH");

if (balance < 500000000000000n) {
  console.error("Need at least 0.0005 ETH for registration gas");
  process.exit(1);
}
```

## 4. Register onchain

Register your agent on the ERC-8004 Identity Registry. This mints an NFT that represents your permanent onchain identity.

### Step 1: Create your registration JSON

Include the `services` array to declare your agent's capabilities so other agents and services can discover what you do:

```typescript
const registration = {
  type: "https://eips.ethereum.org/EIPS/eip-8004#registration-v1",
  name: "Your Agent Name",
  description: "What your agent does",
  image: "https://example.com/your-agent-avatar.png",
  active: true,
  x402Support: false,
  services: [
    { name: "A2A", endpoint: "https://your-agent.example.com/a2a", version: "0.3.0" },
    { name: "MCP", endpoint: "https://your-agent.example.com/mcp", version: "0.1.0" },
  ],
};
```

- **`image`** — URL of your agent's avatar or logo, displayed in explorers and directories. Use a square image (256x256 or larger). If you don't have one yet, set it to `""` and add one later via `setAgentURI`.
- **`services`** — declares your agent's capabilities onchain. Each entry has a `name` (the service identifier), an `endpoint`, and optionally a `version`. Common service types include `A2A` (Agent-to-Agent protocol) and `MCP` (Model Context Protocol).

### Step 2: Encode as a data URI

```typescript
const uri =
  "data:application/json;base64," + Buffer.from(JSON.stringify(registration)).toString("base64");
```

### Step 3: Call register() on the Identity Registry

```typescript
import { encodeFunctionData } from "viem";

const IDENTITY_REGISTRY = "0x8004A169FB4a3325136EB29fA0ceB6D2e539a432";

const registerAbi = [
  {
    inputs: [{ name: "agentURI", type: "string" }],
    name: "register",
    outputs: [{ name: "agentId", type: "uint256" }],
    stateMutability: "nonpayable",
    type: "function",
  },
] as const;

// Estimate gas first
const gas = await publicClient.estimateGas({
  account: account.address,
  to: IDENTITY_REGISTRY,
  data: encodeFunctionData({
    abi: registerAbi,
    functionName: "register",
    args: [uri],
  }),
});

console.log("Estimated gas:", gas.toString());

// Send the transaction
const hash = await walletClient.writeContract({
  address: IDENTITY_REGISTRY,
  abi: registerAbi,
  functionName: "register",
  args: [uri],
});

console.log("TX hash:", hash);
```

### Step 4: Parse the Transfer event to get your token ID

```typescript
const receipt = await publicClient.waitForTransactionReceipt({ hash });

// ERC-721 Transfer event topic
const transferTopic = "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef";
const transferLog = receipt.logs.find(
  (log) =>
    log.topics[0] === transferTopic && log.address.toLowerCase() === IDENTITY_REGISTRY.toLowerCase()
);

const erc8004AgentId = transferLog?.topics[3]
  ? BigInt(transferLog.topics[3]).toString()
  : undefined;

console.log("Your ERC-8004 Agent ID:", erc8004AgentId);
```

### Step 5: Save your agent ID

Save `erc8004AgentId` — this is your permanent onchain identity. Add it to your `.env`:

```
ERC8004_AGENT_ID=42
```

You can verify your registration on BaseScan:
`https://basescan.org/nft/0x8004A169FB4a3325136EB29fA0ceB6D2e539a432/{your_agent_id}`

## 5. Update your registration

After your initial registration, you can update your agentURI (name, description, services) by calling `setAgentURI` on the Identity Registry. This lets you add new capabilities or change your metadata without re-registering.

```typescript
const setAgentUriAbi = [
  {
    inputs: [
      { name: "agentId", type: "uint256" },
      { name: "agentURI", type: "string" },
    ],
    name: "setAgentURI",
    outputs: [],
    stateMutability: "nonpayable",
    type: "function",
  },
] as const;

// Build updated registration JSON
const updatedRegistration = {
  type: "https://eips.ethereum.org/EIPS/eip-8004#registration-v1",
  name: "Your Agent Name",
  description: "Updated description",
  image: "https://example.com/your-agent-avatar.png",
  active: true,
  x402Support: false,
  services: [
    { name: "A2A", endpoint: "https://your-agent.example.com/a2a", version: "0.3.0" },
    { name: "MCP", endpoint: "https://your-agent.example.com/mcp", version: "0.1.0" },
  ],
};

const newUri =
  "data:application/json;base64," +
  Buffer.from(JSON.stringify(updatedRegistration)).toString("base64");

const hash = await walletClient.writeContract({
  address: IDENTITY_REGISTRY,
  abi: setAgentUriAbi,
  functionName: "setAgentURI",
  args: [BigInt(process.env.ERC8004_AGENT_ID!), newUri],
});

console.log("URI updated, TX:", hash);
```

Only the token owner can call `setAgentURI`.

## 6. Contract addresses and verification

| Contract            | Address                                      | Chain        |
| ------------------- | -------------------------------------------- | ------------ |
| Identity Registry   | `0x8004A169FB4a3325136EB29fA0ceB6D2e539a432` | Base mainnet |
| Reputation Registry | `0x8004BAa17C55a88189AE136b182e5fdA19dE9b63` | Base mainnet |

**Verify on BaseScan:**

- Identity Registry: [basescan.org/address/0x8004A169FB4a3325136EB29fA0ceB6D2e539a432](https://basescan.org/address/0x8004A169FB4a3325136EB29fA0ceB6D2e539a432)
- Reputation Registry: [basescan.org/address/0x8004BAa17C55a88189AE136b182e5fdA19dE9b63](https://basescan.org/address/0x8004BAa17C55a88189AE136b182e5fdA19dE9b63)

**Onchain query examples (read-only, no gas):**

```typescript
import { createPublicClient, http } from "viem";
import { base } from "viem/chains";

const client = createPublicClient({ chain: base, transport: http() });

// Check who owns a token
const owner = await client.readContract({
  address: "0x8004A169FB4a3325136EB29fA0ceB6D2e539a432",
  abi: [
    {
      inputs: [{ name: "agentId", type: "uint256" }],
      name: "ownerOf",
      outputs: [{ name: "", type: "address" }],
      stateMutability: "view",
      type: "function",
    },
  ],
  functionName: "ownerOf",
  args: [42n],
});

// Read an agent's metadata URI
const uri = await client.readContract({
  address: "0x8004A169FB4a3325136EB29fA0ceB6D2e539a432",
  abi: [
    {
      inputs: [{ name: "tokenId", type: "uint256" }],
      name: "tokenURI",
      outputs: [{ name: "", type: "string" }],
      stateMutability: "view",
      type: "function",
    },
  ],
  functionName: "tokenURI",
  args: [42n],
});
```

## 7. Resources

- [8004.org](https://8004.org) — ERC-8004 protocol
- [Base](https://base.org) — Base L2 chain
- [BaseScan](https://basescan.org) — Base block explorer
- [viem](https://viem.sh) — TypeScript Ethereum library

## Summary

1. **Set up wallet** — generate a private key, derive address, store securely.
2. **Fund wallet** — get ETH on Base (Coinbase, bridge, or transfer). $1 is more than enough.
3. **Register onchain** — call `register(agentURI)` on the Identity Registry with your services. Parse the Transfer event for your token ID.
4. **Update registration** — call `setAgentURI` to change your metadata or add new services.


---
Source attribution: modbender
Original project: https://github.com/modbender/skill-library-mcp/blob/d9c8fe903b5b4e82237dbe8d0df8567783022e18/data/base-8004/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2025 skill-library-mcp contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: modbender
Original project: https://github.com/modbender/skill-library-mcp/blob/d9c8fe903b5b4e82237dbe8d0df8567783022e18/data/base-8004/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Growth Product Manager, ML / AI Engineer, Product Manager
Specialties: API
Tools: Base, Viem
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: 4060223985cb1a6e7a3948d5cb5b7d7cdc87e92af1570c811ef2d79f8915031d