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

# Detection

> Configure how AgentXP identifies AI agents from incoming requests.

# Detection

> Configure how AgentXP identifies AI agents from incoming requests.

AgentXP inspects each incoming request and determines whether it originates from an AI agent before deciding whether to serve markdown. You can configure which signals it uses and add your own bot patterns.

## How detection works

AgentXP evaluates signals in priority order and stops at the first definitive match:

1. **`accept-header`** — If the request includes `Accept: text/markdown`, AgentXP treats it as an agent with full confidence (`1.0`). This is a deliberate, unambiguous signal that the client expects markdown.
2. **`user-agent`** — AgentXP matches the `User-Agent` string against a list of 20+ known bot patterns. A match yields confidence `0.9`.

If no signal matches, the request is passed through unchanged to your Next.js application.

## Configuration

```typescript middleware.ts theme={null}
import { withAgentXP } from '@reaganhsu/agentxp-next'

export default withAgentXP({
  detection: {
    signals: ['accept-header', 'user-agent'],
    customAgents: [
      { name: 'MyBot', pattern: /MyCustomBot\/\d+/i },
    ],
  },
})
```

## Options

### `signals`

Type: `('accept-header' | 'user-agent' | 'http-signature')[]`

The detection methods AgentXP uses, evaluated in the order listed.

**Default:** `['accept-header', 'user-agent']`

| Value              | Description                                                       |
| ------------------ | ----------------------------------------------------------------- |
| `'accept-header'`  | Match requests with `Accept: text/markdown` (confidence `1.0`)    |
| `'user-agent'`     | Match against known AI bot User-Agent patterns (confidence `0.9`) |
| `'http-signature'` | Reserved for future cryptographic agent verification              |

To restrict detection to only one method, pass a single-element array:

```typescript theme={null}
detection: {
  signals: ['accept-header'],
}
```

### `customAgents`

Type: `{ name: string; pattern: RegExp }[]`

Additional bot patterns to recognize beyond the built-in list. Each entry requires a human-readable `name` and a `RegExp` tested against the request's `User-Agent` string.

**Default:** `[]`

```typescript theme={null}
detection: {
  customAgents: [
    { name: 'AcmeCrawler', pattern: /AcmeCrawler\/\d+\.\d+/i },
    { name: 'InternalAgent', pattern: /internal-agent/i },
  ],
}
```

Custom agents are checked after the built-in patterns. A match yields the same `0.9` confidence as other `user-agent` matches.

## Built-in agent patterns

The following agents are recognized out of the box via the `user-agent` signal:

| Agent                | Pattern                |
| -------------------- | ---------------------- |
| GPTBot               | `GPTBot`               |
| ChatGPT-User         | `ChatGPT-User`         |
| OAI-SearchBot        | `OAI-SearchBot`        |
| ClaudeBot            | `ClaudeBot`            |
| Anthropic            | `anthropic-ai`         |
| PerplexityBot        | `PerplexityBot`        |
| Bytespider           | `Bytespider`           |
| Cohere               | `cohere-ai`            |
| GoogleOther          | `GoogleOther`          |
| Google-Extended      | `Google-Extended`      |
| Meta-ExternalAgent   | `Meta-ExternalAgent`   |
| Meta-ExternalFetcher | `Meta-ExternalFetcher` |
| CCBot                | `CCBot`                |
| Applebot-Extended    | `Applebot-Extended`    |
| Amazonbot            | `Amazonbot`            |
| AI2Bot               | `AI2Bot`               |
| Diffbot              | `Diffbot`              |
| FacebookBot          | `FacebookBot`          |
| YouBot               | `YouBot`               |
| Webzio-Extended      | `Webzio-Extended`      |

For the full list with regex patterns, see [Supported Agents](/docs/reference/supported-agents).