llms.txt.

What is llms.txt?

llms.txt is a proposed plain-text file, placed at the root of a website, that gives large language models a short Markdown summary of the site and links to its most useful pages. Jeremy Howard of Answer.AI proposed it in September 2024 as a way to help AI tools read sites without wading through cluttered HTML. It remains a community proposal with no formal standards body behind it.

Why it matters

The commercial question is whether it changes how AI tools see your business, and so far the evidence says it does not. Google's John Mueller has said AI services do not appear to check for the file, and Google's May 2026 guidance told site owners they need no special AI text files to appear in its generative features. Adding one costs little; the risk is paying for it as if it were a visibility strategy.

Where it stands

• The format A Markdown file at yoursite.co.uk/llms.txt with a title, a short summary and lists of key links.
• Google Search ignores it Google has said its search systems do not use the file and that no special AI files are needed.
• Some agent interest Parts of Google's developer tooling now treat it as an emerging convention for AI agents, which is a separate question from search visibility.
• Best current use Developer documentation sites, where coding assistants are deliberately pointed at it.

What to do about it

Do not spend budget on it. If your developer can add a simple llms.txt in half an hour, there is little harm, but treat it as housekeeping. The time is better spent making sure your key pages load quickly, state your services and prices clearly, and are open to the crawlers AI tools use. Check your robots.txt and any firewall or security settings for accidental blocks; that matters far more.