What we measured about it: 5,400 times a month of demand, mostly answered with hype in both directions; this page is the measured middle.
Run on your market, a read shows: which AI surfaces actually fetch and cite your site today, and your real search demand under every phrasing, which AI answers in your market are open, partial or closed (with the evidence), what your competitors run in the public ad archives, and your break-even numbers computed from your own economics.
Book the 20-minute callor read the measured pieces first →What is llms.txt?
llms.txt is a proposed web standard: a markdown file served at /llms.txt that gives AI systems a curated map of a site's most important content, the way robots.txt gives crawlers rules. It was proposed in 2024 and adoption is real among documentation sites and developer tools, but no major AI provider has publicly committed to consuming it as a ranking or citation input, which means it is currently a low-cost courtesy, not a lever with measured effect. The term is searched 5,400 times a month in the US, with the practical tail ('llms.txt file' 880 searches a month, 'generator' 480 searches a month, 'what is' 480 searches a month, 'validator' 90 searches a month) confirming implementer intent. (Nukebook, 2026-08-28.)
That paragraph is the whole honest state of it: cheap to add, plausibly useful, unproven as a lever. We serve one ourselves at /llms.txt, because a few minutes of cost against a plausible benefit is a fine trade as long as nobody pretends it is magic. measured
How to write one in ten minutes
One H1 with the site's name, a one-line summary, then short sections linking your genuinely important pages with one-line descriptions each. Markdown, plain, honest. Skip the keyword stuffing: the file's only plausible reader is a machine deciding whether your content answers a question.
What to watch instead of believing
Your server logs (are AI crawlers fetching it?), and your citation record (did anything change after adding it?). If a vendor sells you llms.txt optimization as a guaranteed visibility lever, refer them to the paragraph above: unproven means unproven in both directions.
One read: your demand, your winnable AI answers, every competitor's ads, and your site's catch rate. Price and scope on a short call, plainly.
Book a call or see what a read contains →