Is your llms.txt actually valid?

The llmstxt.org convention is simple: a single '# Your Site Name' title, an optional one-line '>' summary underneath, then '##' sections (Docs, Blog, Products) whose bodies are lists of '- [Page title](https://full-url): short description' lines. Plain markdown, served as plain text at yoursite.com/llms.txt.

Serving an HTML page where the text file should be. Many hosts return the app shell or a styled 404 for unknown paths with a 200 status, so the file looks present but a crawler reading it gets HTML soup. This validator checks the response content before anything else.

An AI crawler reads llms.txt as a standalone document, often far from your site. A relative path like /docs/setup only works if the reader remembers which domain it came from; a full https:// URL always works. The convention uses absolute URLs throughout.

Neither. It is an emerging convention, not a standard, and no AI assistant is obligated to read or honor it. What it does is make your site cheaper to understand for the crawlers that do support it: a curated map instead of a blind crawl. Think of it as low-cost, low-guarantee hygiene.

robots.txt says who may crawl and what they may touch. llms.txt says what the site is and which pages matter most. One is access control, the other is a guided tour. They live side by side at your domain root and do not overlap.

Each failed check comes with the fix in plain English. If you would rather start over, our free llms.txt generator reads your sitemap and assembles a valid file you can edit and download in about a minute.

No. We fetch the file live, server-side (browsers cannot fetch other sites directly), grade it in your browser, and keep nothing. Nothing is logged against your domain or saved.