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Quickstart

Send your first paid AI request in under a minute.

Basic Usage

import { X402OpenAI } from 'x402-openai';
import { EvmWallet } from 'x402-openai/wallets';

const client = new X402OpenAI({
wallet: new EvmWallet({ privateKey: '0x…' }),
});

const res = await client.chat.completions.create({
model: 'openai/gpt-4o-mini',
messages: [{ role: 'user', content: 'Hello!' }],
});
console.log(res.choices[0]?.message.content);

When the server returns 402 Payment Required, the SDK automatically signs a payment and retries — you only see the final response.

Custom Base URL

Point the client at any x402-compatible endpoint:

const client = new X402OpenAI({
wallet: new EvmWallet({ privateKey: '0x…' }),
baseURL: 'https://your-server.example.com/v1',
});

Using Solana

Swap the wallet adapter — the API is identical:

import { SvmWallet } from 'x402-openai/wallets';

const client = new X402OpenAI({
wallet: new SvmWallet({ privateKey: 'base58…' }),
});

Next Steps

  • Wallets — BIP-39 mnemonics, multi-chain setups
  • Streaming — streaming responses
  • Policies — control chain and amount preferences