What is llms.txt?
Definition
llms.txt is a proposed plain-Markdown file at a site's root that gives AI systems a curated summary of the site and links to its most important pages.
The format was proposed at llmstxt.org: an H1 with the site's name, a short blockquote summary, and sections of annotated links. Some AI tools and agents read it, and developer documentation sites publish it widely.
Google Search does not use it. Google's AI features documentation says "You don't need to create new machine readable files, AI text files, or markup to appear in these features." So llms.txt is not a Google tactic, and anyone promising it will boost your rankings is overselling. Its honest case is small: it takes minutes, it gives any system that does read it your preferred framing, and a clear summary of your business is worth writing anyway. This site publishes one. It does not replace robots.txt, which controls access rather than describing content.
Why does it matter to your business?
It is cheap insurance, not a strategy. Spend the minutes on it, and the hours on the content it points to.
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Sources, verified September 11, 2026
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