AI Crawlers: Who is Visiting Your Website?
Web traffic patterns have shifted. While traditional search bots continue to scan directories, a new class of AI crawlers are visiting sites daily to retrieve training and real-time query data. Ensure your assets are correctly structured by reading what is the llms.txt standard guide.
Key Takeaways
- AI bots crawl sites under custom User-Agents like GPTBot and ClaudeBot.
- Robots.txt rules can restrict AI crawler indexing but also block llms.txt discovery.
- Allowing AI crawlers ensures correct citations in generated search answers.
- Maintain clear Markdown files to optimize ingestion budgets for search engines.
1. The Primary AI Crawling Engines
AI search engines and models operate custom crawler agents. The main User-Agents currently active include:
- GPTBot: OpenAI's primary crawler, scanning pages to train GPT models.
- ClaudeBot: Anthropic's crawler, designed to compile data for the Claude models.
- Google-Extended: Used by Google to allow website owners to control whether their content is used for Gemini model training.
- Applebot-Extended: Apple's crawler for Apple Intelligence.
Active AI Crawler Agents Comparison
| Crawler Name | User-Agent Token | Operator / Platform | Primary Purpose |
|---|---|---|---|
| GPTBot | GPTBot |
OpenAI | Training data and web index |
| ClaudeBot | ClaudeBot |
Anthropic | Model training ingestion |
| Google-Extended | Google-Extended |
Gemini model training opt-out | |
| Applebot-Extended | Applebot-Extended |
Apple | Apple Intelligence training data |
2. Controlling AI Access via Robots.txt
You can manage AI bot access directly in your robots.txt file:
User-agent: GPTBot
Disallow: /
User-agent: ClaudeBot
Disallow: /llms.txt file. For a detailed guide on exclusion setups, read our llms.txt vs robots.txt differences guide.
3. The Case for Allowing AI Crawlers
While blocking AI bots is a common approach, allowing them to crawl your site can ensure your brand is cited and referenced accurately in generative answers. Hosting an llms.txt file helps these crawlers index your pages efficiently. Ensure your site is compliant with our live LLMs.txt Validator tool. Learn more about the ranking mechanics in our Generative Engine Optimization guide.
Frequently Asked Questions
An AI crawler is a specialized web spider used by artificial intelligence companies to scrape and compile data to train and query models.
OpenAI uses the User-Agent 'GPTBot' to crawl public web pages for model training.
Anthropic's models crawl web content using the User-Agent token 'ClaudeBot'.
Google uses 'Google-Extended' to let site owners opt out of Gemini model training, while traditional indexing still runs via Googlebot.
Add a disallow rule inside robots.txt targeting User-agent: GPTBot and Disallow: /.
No. Blocking AI training crawlers (like GPTBot or Google-Extended) does not affect your position in traditional Google Search.
Perplexity uses search API indices and custom crawlers to query resources dynamically in response to user prompts.
Allowing crawlers helps ensure your brand is cited and referenced accurately in generative answers.
Yes, Apple uses the User-Agent 'Applebot-Extended' to fetch content for Apple Intelligence training.
They check the root path (domain.com/llms.txt) of your site automatically during their initial crawl pass.