@aiedx/fetchlens-next

AI bot detection middleware for Next.js. Detects 26 AI agents (GPTBot, ClaudeBot, PerplexityBot, and more) hitting your site in real-time. Works on any host — Vercel, AWS Amplify, Netlify, Cloudflare, self-hosted.

Why

Google Analytics, Plausible, and every other analytics tool are 100% blind to AI bot traffic. These bots don't run JavaScript, so they never appear in your dashboards. FetchLens detects them at the middleware layer.

Install

npm install @aiedx/fetchlens-next

Setup

Create middleware.ts in your project root:

import { withFetchLens } from '@aiedx/fetchlens-next'

export const middleware = withFetchLens({
  siteId: 'yourdomain.com',
  apiEndpoint: 'https://fetchlens.ai',
  siteTag: 'fl_pub_your_key',
})

export const config = {
  matcher: ['/((?!_next/static|_next/image|favicon.ico|api/).*)'],
}

Get your Site Tag by scanning your domain at fetchlens.ai.

What it detects

| Provider | Bots | |----------|------| | OpenAI | GPTBot, ChatGPT-User, OAI-SearchBot | | Anthropic | ClaudeBot, Claude-SearchBot, Claude-User, Claude-Code, anthropic-ai | | Perplexity | PerplexityBot, Perplexity-User | | Google | Google-Extended, Google-CloudVertexBot | | Apple | Applebot-Extended | | Meta | meta-externalagent, meta-externalfetcher, FacebookBot | | Others | DuckAssistBot, MistralAI-User, Bytespider, cohere-ai, Amazonbot, PetalBot, Diffbot, PhindBot, YouBot, CCBot |

Features

• Zero-latency — detection runs asynchronously via waitUntil, no impact on page load
• Vulnerability scan blocking — automatically blocks probes for .php, /wp-admin, .env, etc. with a 403 (configurable)
• Server-side only — no client bundle impact, works with all rendering modes (SSR, SSG, ISR)
• 26 AI bot signatures — covers all major AI crawlers and training bots

Configuration

withFetchLens({
  siteId: 'yourdomain.com',        // Required: your domain
  apiEndpoint: 'https://fetchlens.ai', // Required: FetchLens API URL
  siteTag: 'fl_pub_xxx',           // Your Site Tag (from install guide)
  blockVulnScans: true,            // Block vulnerability probes (default: true)
})

How it works

1. Every request passes through Next.js middleware
2. FetchLens extracts the user agent, headers, and request metadata
3. The payload is sent asynchronously to the FetchLens API (zero latency impact)
4. The API identifies the bot using 26 known signatures + heuristic detection
5. Results appear on your FetchLens dashboard

Requirements

• Next.js 14+
• Node.js 18+

License

Proprietary. Copyright (c) 2026 AIEDX Private Limited.