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

# Introduction

> x402 payment infrastructure for AI agents — route USDC micropayments between AI bots and publishers on Base L2. Non-custodial, 0% fee, pay-per-crawl.

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Xenarch is a non-custodial payment layer that lets publishers charge AI agents for content and services using the [x402 protocol](https://www.x402.org/). Agents pay USDC on Base L2 through a splitter smart contract. Publishers receive funds directly — Xenarch never holds anyone's money.

## What Xenarch does

* **For publishers**: Gate content behind HTTP 402 responses. Bots pay USDC, humans pass through unaffected.
* **For agents**: Discover pricing via `pay.json` or HTTP 402, pay on-chain, receive time-limited access tokens.
* **For platforms**: Integrate via Python/TypeScript SDKs, MCP server, or CMS plugins.

## How payments work

```
Agent requests content → Server returns HTTP 402 with gate details
Agent sends USDC to splitter contract → Contract splits to publisher + treasury
Agent submits tx hash to verify endpoint → Server returns access token
Agent re-requests content with Bearer token → Server returns content
```

Every payment is a single on-chain USDC transfer. No deposits, no balances, no custody. The splitter contract has an immutable fee cap of 0.99% (currently 0%).

## Key properties

| Property         | Value                            |
| ---------------- | -------------------------------- |
| **Settlement**   | USDC on Base L2                  |
| **Max payment**  | \$1.00 per transaction           |
| **Fee**          | 0% (capped at 0.99% forever)     |
| **Custody**      | None — permanently non-custodial |
| **Verification** | On-chain, auditable on Basescan  |
| **Protocol**     | x402 (HTTP 402 Payment Required) |

## Next steps

<CardGroup cols={2}>
  <Card title="Agent quickstart" icon="robot" href="/quickstart-agent">
    Start paying for gated content in 5 minutes.
  </Card>

  <Card title="Publisher quickstart" icon="server" href="/quickstart-publisher">
    Start charging AI agents for your content.
  </Card>

  <Card title="API reference" icon="code" href="/api-reference/overview">
    Full REST API documentation.
  </Card>

  <Card title="Examples" icon="book" href="/examples/overview">
    Working code for Python, LangChain, CrewAI, and MCP.
  </Card>
</CardGroup>