llms.txt checker
Does your site have a valid llms.txt?
llms.txt is a plain-text file at your site's root — like robots.txt, but written for AI models instead of crawlers' allow/deny rules. It gives ChatGPT, Claude, Perplexity, and other engines a concise, curated summary of what your site is and where its important pages live. Enter your domain to check yours.
What the check covers
What a good llms.txt looks like
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Exists at /llms.txt
Served at the site root with a plain-text content type, not a redirect to an HTML page or a 404.
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Follows the expected structure
An H1 with the site name, a short summary blockquote, then markdown link sections pointing to your most important pages.
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Links resolve
The pages it lists actually exist and are crawlable — a summary file pointing at blocked or dead URLs helps nobody.
We publish our own, by the way: visibilityzen.com/llms.txt.
The honest part
Is llms.txt enough?
No — it's one signal of about twenty, and Google says it doesn't affect Google's AI features. That's why we fix the whole stack: crawler access (GPTBot, OAI-SearchBot, ClaudeBot, PerplexityBot), schema, sitemap health, entity clarity, and whether AI engines actually mention your brand. The scan above checks all of it, not just the one file.