llms.txt
Definition
llms.txt is a proposed Markdown file, published at the top level of a domain as yourdomain.com/llms.txt, that gives language models a short guide to the site and its key pages. It is a proposal rather than an adopted standard, and Google says Search does not use it.
Jeremy Howard published the proposal on 3 September 2024. The file opens with the site's name as a heading, adds a one-line summary, then lists the important pages with a short note on each. It does a different job from robots.txt: that file controls which crawlers may visit, while llms.txt can only suggest what is worth reading, so it can neither grant nor block access.
The evidence for it is thin. Google's guide to generative AI features says you don't need AI text files such as llms.txt and that Search doesn't use them, so a file won't move Google rankings or AI Overviews in either direction. OpenAI hasn't confirmed that it reads the file; one trade report in July 2025 described a single site's logs showing OpenAI fetching one, which is an observation, not a confirmation. Search Engine Journal reported in May 2026 that Chrome's Lighthouse 13.3 audits the file, but that is a separate product and not a Search signal.
Publish one only if it can be generated from data you already keep, such as your CMS or sitemap, and one named person owns it. A hand-written file goes stale, and a stale file is a second place for your prices to be wrong. Never pay a monthly fee for it, and don't expect it to move a ranking.
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