Glossary /AI search & GEO
llms.txt
A proposed file at a site’s root that gives language models a curated, plain-text summary of what the site contains.
llms.txt is a convention: a Markdown file at the root of a domain that describes the site in plain language and links to its most important pages. The intent is to give a model a clean, curated entry point rather than making it infer a site’s purpose from crawling whatever it happens to reach.
It is a proposal, not a standard. No major assistant has committed to reading it, and it should be understood as cheap and speculative rather than as an established requirement — a well-maintained one costs an hour and might pay off, which is a defensible trade at that price.
It is worth distinguishing from robots.txt, which it superficially resembles. robots.txt restricts what may be fetched; llms.txt asserts what is worth reading. One is a boundary and the other is a summary, and neither substitutes for the other.