How LLMs Read Your Site: robots.txt and llms.txt
Before worrying about content quality, confirm AI crawlers are even allowed onto your site via robots.txt, and consider adding an llms.txt file.
major AI crawlers worth explicitly listing in robots.txt
first technical check before any GEO work: is robots.txt blocking these crawlers?
llms.txt is an emerging standard simplifying site structure for LLMs
If robots.txt blocks GPTBot, ClaudeBot, or PerplexityBot, your content is completely invisible to these systems regardless of quality — this is the first technical check before any GEO work.
Crawlers You Should Allow
GPTBot and OAI-SearchBot (OpenAI), ClaudeBot and anthropic-ai (Anthropic), PerplexityBot, Google-Extended (Gemini), and Applebot. Each has a distinct user-agent that must be explicitly listed in robots.txt.
The New llms.txt File
llms.txt is a newly proposed text file (think sitemap.xml but for language models) placed at the site root, listing links to your most important pages in simplified Markdown so models can quickly grasp site structure without parsing complex HTML.
Questions & Answers
01Does blocking these crawlers protect my content from theft?
Blocking them prevents your site from appearing in AI answers entirely — the opposite of GEO's goal. Allowing crawling to benefit from visibility is usually preferable.
02Is llms.txt mandatory?
No, it's an emerging optional standard not officially adopted by every company, but it's a good, low-cost practice.
Need to Apply These Ideas to Your Project?
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