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AI & Search

AI Crawler

GPTBot | AI Bot | LLM Crawler

Portrait of Lukas Horvath, co-founder of Roelu Studio
Lukas HorvathCo-founder

What is AI Crawler?

An AI crawler is an automated program that fetches web pages on behalf of an AI company, either to train its models or to retrieve fresh content for live answers. Common AI crawlers include GPTBot from OpenAI, ClaudeBot from Anthropic, PerplexityBot, Google-Extended, and Meta-ExternalAgent. Each identifies itself with a specific user agent string, which means you can choose to allow, block, or rate-limit it in your robots.txt.

Why it matters

Your robots.txt is now a strategic decision, not a developer afterthought. Block every AI crawler and you protect your content from training datasets — but you also disappear from ChatGPT Search, Perplexity, and Google AI Overviews when those tools fetch pages live. Allow them all and you trade reach for control. Most teams pick the middle: block the training crawlers, allow the retrieval ones. Either way, the decision should be deliberate, owned by marketing and legal together, and reviewed quarterly. Pretending these bots are not a category is how brands end up cited inconsistently or not at all.

How it works

AI crawlers follow the same protocol as Googlebot — they request pages, parse the HTML, and store what they find. The difference is what happens next. Training crawlers like GPTBot and Google-Extended feed content into model training pipelines. Retrieval crawlers like ChatGPT-User, OAI-SearchBot, and PerplexityBot fetch pages on demand when a user asks a question. Each respects robots.txt directives, so you can disallow specific user agents. Some teams also use Cloudflare's AI bot controls or similar tools to rate-limit aggressive bots that ignore robots.txt or scrape at scale. Your server logs show which bots visit, how often, and which pages they hit — useful data when you are deciding the policy.

Related terms

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