llms.txt is a proposed plain-text file that gives AI systems a short guide to your most important content. There’s no clear evidence that the major AI search engines rely on it today, and Google representatives have said publicly that Google Search doesn’t use it. It’s cheap to create and harmless, so add it last, after the things that are known to matter.
What llms.txt is
The idea, proposed in 2024, is a Markdown file at yoursite.com/llms.txt. It contains a title, a one-line summary, and lists of links to your key pages with a short description of each. The goal is to give language models a clean, curated map of a site without them having to parse navigation, scripts and layout.
A minimal example:
# Acme Ledger
> Accounting software for small creative agencies in India.
## Product
- [Pricing](https://acmeledger.com/pricing): plans and what each includes
- [Features](https://acmeledger.com/features): invoicing, GST, project billing
## Guides
- [Choosing accounting software](https://acmeledger.com/guides/choosing): criteria and comparisonWhat the evidence says
Adoption by site owners has grown, especially among software and documentation sites. Adoption by AI search engines is a different question. As of this writing:
- None of the major AI search products has documented that it uses llms.txt to choose or rank sources.
- Google has said Search doesn’t use it.
- Some developer tools and coding assistants do use similar files to load documentation, which is where the idea is most useful today.
How to treat it
Think of llms.txt as an optional extra with low cost and uncertain benefit. The things that are known to affect AI visibility are:
- letting AI search crawlers fetch your pages,
- making your brand facts consistent everywhere,
- writing pages that answer buyer questions directly,
- getting mentioned on the sites engines already cite.
If those are in place, spend an hour on an llms.txt. If they aren’t, the hour is better spent on them.
Keep it accurate
If you do publish one, keep it in step with your site. A file listing old pricing or retired pages is worse than no file. Add it to whatever checklist you use when you update key pages.
Frequently asked questions
Does Google use llms.txt?
Google representatives have said publicly that Google Search doesn’t use it.
Is llms.txt harmful?
No. It’s a plain-text file that takes about an hour to create. Keep it accurate if you publish one.
Where does llms.txt go?
At the root of your site, for example yoursite.com/llms.txt, written in Markdown.