> ## 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.

# API Overview

> x402 REST API reference — payment gates, USDC micropayments on Base, publisher registration, and AI agent management. Complete x402 API docs.

## Base URL

```
https://xenarch.dev/v1
```

All endpoints are prefixed with `/v1`. The API returns JSON responses.

## Authentication

Three authentication methods depending on the caller:

| Method            | Header             | Format              | Used by                          |
| ----------------- | ------------------ | ------------------- | -------------------------------- |
| Publisher API key | `Authorization`    | `Bearer xk_pub_...` | Publishers managing sites        |
| Site token        | `X-Site-Token`     | `st_...`            | Server middleware creating gates |
| Wallet address    | `X-Wallet-Address` | `0x...`             | Agents querying profiles         |

See [Authentication](/api-reference/authentication) for details.

## Rate limits

| Endpoint                       | Limit   | Scope          |
| ------------------------------ | ------- | -------------- |
| `POST /v1/publishers/register` | 5/min   | Per IP         |
| `POST /v1/publishers/login`    | 5/min   | Per IP         |
| `POST /v1/gates`               | 200/min | Per site token |
| `POST /v1/gates/{id}/verify`   | 50/min  | Per gate       |
| All other endpoints            | 100/min | Per credential |

Rate-limited responses return HTTP 429 with a `Retry-After` header.

## Error format

```json theme={null}
{
  "detail": "Gate not found or expired"
}
```

All errors include a `detail` field with a human-readable message.

## Common status codes

| Code | Meaning                          |
| ---- | -------------------------------- |
| 200  | Success                          |
| 201  | Created                          |
| 400  | Bad request (validation error)   |
| 401  | Invalid or missing credentials   |
| 402  | Payment required (gate response) |
| 404  | Resource not found               |
| 409  | Conflict (duplicate resource)    |
| 429  | Rate limited                     |
| 500  | Server error                     |