llms.txt is a proposed convention: a Markdown file at the root of your site (yourdomain.com/llms.txt) that hands AI systems a short, curated map of what matters — your key pages, products, and a one-line description of each — in a format that's trivial for a model to parse.
Think of it as a counterpart to robots.txt, but inverted: robots.txt says what crawlers may access; llms.txt says what they should pay attention to. Instead of making an engine infer your site's structure from messy HTML, you tell it plainly.
It's still an emerging standard — adoption is growing but not universally honoured yet, so treat it as a low-cost, high-signal addition rather than a guarantee. For brands it's a cheap way to point AI at your best, most accurate content. (There's also llms-full.txt, a fuller single-file dump of site content for the same purpose.)
