GEO Glossary
llms.txt
llms.txt is a plain-text file at a site's root (domain.com/llms.txt) that summarizes, in clear language with links, what the organization is and what its most important content is, so AI models can interpret it without noise.
Updated on September 8, 2026
llms.txt is a plain-text file placed at the root of a domain —for example, getlumen.lat/llms.txt— that gives language models a curated summary of the site: what the organization is, what it does, and which pages are worth reading. It is analogous to robots.txt or sitemap.xml, but aimed at AI assistants rather than search crawlers. It is part of GEO and AEO best practice.
What is it for?
Web pages are full of menus, banners and scripts that dilute the message. An llms.txt file delivers a clean, prioritized version of the content, with links to the key pages and a description of each. It reduces the risk of the model misinterpreting the brand and increases the chance it cites it correctly.
How do you implement it?
- Create a file named llms.txt and publish it at the domain root (reachable at /llms.txt).
- Use Markdown: a heading with the name, a summary paragraph (blockquote), and sections with link lists.
- Each link carries a sentence describing what is on that page.
- Prioritize: product, pricing, documentation, and the content you want AI to cite.
- Keep it current — add every important new page or article.
Do the models use it yet?
Adoption is in progress and not every provider confirms they read it. Even so, the cost of publishing it is low and the potential benefit —a clear, brand-controlled source— is high. Many GEO vendors recommend it as a baseline step.
Is llms.txt the same as robots.txt?+
Do I need llms.txt if I already have sitemap.xml?+
How do I know if my llms.txt is helping?+
Lumen AI also generates and maintains your llms.txt automatically.
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