Agent quickstart

Build agents that can safely discover and use paid MCP (Model Context Protocol) tools without creating vendor accounts or managing API keys. With ATXP, your agent brings a wallet and pays per request, so you can start building immediately and ship faster.

Why build with ATXP?

Reduced friction: Try new tools in minutes—no signups, no keys, no billing setup.
Pay-as-you-go cost control: Per-MCP-tool-call pricing; you only pay for what you use.
Better security: Keep secrets out of your app; requests are authorized with signed payments instead of shared keys.
Composable tooling: Combine multiple paid MCP servers behind a single client and consistent API.

Build your first ATXP agent

Install the library

Install the ATXP client SDK in your project:

npm install @atxp/client

Set up your account

Create an ATXP account and set your account connection string in an environment variable. The best way to do this is to create a .env file in the root of your project and add the following line:

.env

ATXP_CONNECTION=https://accounts.atxp.ai?connection_token=<random_string>

You can use ATXP to pay for MCP tool calls made from within a Base Mini App. This approach uses a paymaster to pay for gas on behalf of the Mini App’s end-users.In order to use a ATXP with a Base Mini App, you must have a Base Mini App API key from the Coinbase Developer Portal. You then need to set the Base Mini App API key in an environment variable. The best way to do this is to create a .env file in the root of your project and add the following line:

.env

NEXT_PUBLIC_ONCHAINKIT_API_KEY=<YOUR_NEXT_PUBLIC_ONCHAINKIT_API_KEY>

If you already have a Base wallet, you can use it in your ATXP agent by setting the Base endpoint and your Base private key in environment variables. The best way to do this is to create a .env file in the root of your project and add the following lines:

.env

BASE_RPC_URL=<YOUR_BASE_RPC_URL>
BASE_PRIVATE_KEY=<YOUR_BASE_PRIVATE_KEY>

If you already have a Solana wallet, you can use it in your ATXP agent by setting the Solana endpoint and your Solana private key in environment variables. The best way to do this is to create a .env file in the root of your project and add the following lines:

.env

SOLANA_RPC_URL=<YOUR_SOLANA_RPC_URL>
SOLANA_PRIVATE_KEY=<YOUR_SOLANA_PRIVATE_KEY>

For browser applications: ATXP Polygon works with any EIP-1193 compatible wallet provider (e.g., MetaMask, Coinbase Wallet). Users will sign transactions directly with their wallet and pay gas fees in POL. No environment variables are needed.For server/CLI applications: If you’re building a backend service or CLI tool, set the Polygon endpoint and your Polygon private key in environment variables. The best way to do this is to create a .env file in the root of your project and add the following lines:

.env

POLYGON_RPC_URL=<YOUR_POLYGON_RPC_URL>
POLYGON_PRIVATE_KEY=<YOUR_POLYGON_PRIVATE_KEY>

Never commit your .env file to version control. It is a good idea to add your .env to your .gitignore file to prevent it from being committed.

echo .env >> .gitignore

Define the services that you want to use

Define the services that you want to use in your client.

const browseService = {
  mcpServer: 'https://browse.mcp.atxp.ai/',
  toolName: 'atxp_browse',
  description: 'browse',
  getArguments: (prompt: string) => ({ query: prompt }),
  getResult: (result: any) => result.content[0].text
};

Create an ATXP client

Create a client using an ATXP account by importing the ATXP client SDK and other dependencies.

// Import the ATXP client SDK
import { atxpClient, ATXPAccount } from '@atxp/client';

// Read the ATXP account details from environment variables
const atxpConnectionString = process.env.ATXP_CONNECTION;

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account: new ATXPAccount(atxpConnectionString),
});

Create a client using a Base Mini App account by importing the ATXP client SDK and other dependencies.

// Import the ATXP client SDK
import { useAccount } from "wagmi";
import { atxpClient } from '@atxp/client';
import { BaseAppAccount } from '@atxp/base';

// Read the Base mini app API key details from the environment variables
const apiKey = process.env.NEXT_PUBLIC_ONCHAINKIT_API_KEY;
const { address } = useAccount();

// Create a BaseAppAccount object using the mini app API key
const account = await BaseAppAccount.initialize({
  walletAddress: address,
  apiKey,
  appName: 'Mini App with ATXP',
  allowance: BigInt('10000000'), // 10 USDC
  periodInDays: 30,
});
// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account: account,
});

Create a client using a Base account by importing the ATXP client SDK and other dependencies.

// Import the ATXP client SDK and Base account
import { atxpClient } from '@atxp/client';
import { BaseAccount } from '@atxp/base';

// Read the Base account details from the environment variables
const baseRpcUrl = process.env.BASE_RPC_URL;
const basePrivateKey = process.env.BASE_PRIVATE_KEY;

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account: new BaseAccount(baseRpcUrl, basePrivateKey),
});

Create a client using a Solana account by importing the ATXP client SDK and other dependencies.

// Import the ATXP client SDK and Solana account
import { atxpClient } from '@atxp/client';
import { SolanaAccount } from '@atxp/solana';

// Read the Solana account details from the environment variables
const solanaRpcUrl = process.env.SOLANA_RPC_URL;
const solanaPrivateKey = process.env.SOLANA_PRIVATE_KEY;

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account: new SolanaAccount(solanaRpcUrl, solanaPrivateKey),
});

Create a client using a Worldchain account with MiniKit integration.

// Import the ATXP client SDK and Worldchain account creator
import { atxpClient } from '@atxp/client';
import { createMiniKitWorldchainAccount } from '@atxp/worldchain';
import { MiniKit } from '@worldcoin/minikit-js';

// Create a Worldchain account using MiniKit
const account = await createMiniKitWorldchainAccount({
  walletAddress: '0x1234...', // User's wallet address
  miniKit: MiniKit
});

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account,
});

Browser applications:

// Import the ATXP client SDK and Polygon browser account
import { atxpClient } from '@atxp/client';
import { PolygonBrowserAccount } from '@atxp/polygon';

// Initialize the Polygon browser account with wallet provider
const account = await PolygonBrowserAccount.initialize({
  provider: window.ethereum, // or any EIP-1193 provider
  walletAddress: '0x1234...', // User's wallet address
});

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account,
});

Server/CLI applications:

// Import the ATXP client SDK and Polygon server account
import { atxpClient } from '@atxp/client';
import { PolygonServerAccount } from '@atxp/polygon';

// Read the Polygon account details from the environment variables
const polygonRpcUrl = process.env.POLYGON_RPC_URL;
const polygonPrivateKey = process.env.POLYGON_PRIVATE_KEY;

// Create a Polygon server account
const account = new PolygonServerAccount(
  polygonRpcUrl,
  polygonPrivateKey,
  137 // Chain ID: 137 = Polygon mainnet, 80002 = Amoy testnet
);

// Create a client using the `atxpClient` function
const client = await atxpClient({
  mcpServer: browseService.mcpServer,
  account,
});

Use the services in your agent

Use the services in your agent.

const prompt = "What are the top 3 articles by points on https://news.ycombinator.com?";

try {
  const result = await client.callTool({
      name: browseService.toolName,
      arguments: browseService.getArguments(prompt),
  });
  console.log(`${browseService.description} result successful!`);
  console.log('Result:', browseService.getResult(result));
} catch (error) {
  console.error(`Error with ${browseService.description}:`, error);
  process.exit(1);
}

Overview

Build Agents

Monetize MCP Tools

Developer Tools

API Reference

Why build with ATXP?

Build your first ATXP agent

Resources

Account Portal

Build an agent using paid MCP servers

Monetize your MCP server

Overview

Build Agents

Monetize MCP Tools

Developer Tools

API Reference

Documentation Index

​Why build with ATXP?

​Build your first ATXP agent

​Resources

Account Portal

Build an agent using paid MCP servers

Monetize your MCP server

Why build with ATXP?

Build your first ATXP agent

Resources