> ## Documentation Index
> Fetch the complete documentation index at: https://docs.neurobro.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# x402

> Pay-per-request access to Neurobro over the HTTP 402 protocol

x402 is Neurobro's pay-per-request API. There are no API keys and no subscription - you pay **\$1 USDC per query** over the HTTP 402 protocol (USDC on Base), and your wallet is the authentication. It exposes 40+ crypto-analysis tools from the Neurobro agent.

## How it works?

* **No account, no keys** - your wallet is the auth.
* **Pay per call** - \$1 USDC on Base per query, settled over HTTP 402.
* **40+ tools** - the same crypto-analysis toolkit that powers Neurobro.

## Where to begin?

Start with the [**cookbook**](https://github.com/axioma-ai-labs/x402-neurobro) for ready-to-run examples, then point your requests at the [**x402 API**](https://x402.neurobro.ai). New to the protocol itself? [x402.org](https://x402.org) explains how HTTP 402 payments work.

<CardGroup cols={3}>
  <Card title="Cookbook" icon="book" href="https://github.com/axioma-ai-labs/x402-neurobro">
    Ready-to-run examples - start here
  </Card>

  <Card title="x402 API" icon="wallet" href="https://x402.neurobro.ai">
    x402.neurobro.ai
  </Card>

  <Card title="Protocol" icon="link" href="https://x402.org">
    x402.org
  </Card>
</CardGroup>