Sooner or later someone tells you to add an llms.txt file. Here is what it is, what we know about it, and how to decide.
What it is
llms.txt is a plain text file in Markdown, placed at the root of your site (yoursite.com/llms.txt). It was proposed by Jeremy Howard in September 2024 as a convention: a short, curated map of your most useful pages, written for AI tools instead of for people.
A typical file has a title, a one or two line summary, and groups of links with a short description each:
# Your Company
> One or two sentences on what you sell and who it is for.
## Products
- [Product overview](https://yoursite.com/product): What it does and who it suits
- [Pricing](https://yoursite.com/pricing): Plans, limits and what is included
## Help
- [FAQ](https://yoursite.com/faq): Answers to the questions buyers ask mostWhat is unproven
It is a proposal, not a standard. Here is what we found when we checked.
- Google says you don't need it. Google's guidance on AI features says: "You don't need to create new machine readable files, AI text files, or markup to appear in these features." The page was last updated December 10, 2025.
- One large study found no link. SE Ranking looked at nearly 300,000 domains. About 10% (10.13%) had an llms.txt file. Having one showed no correlation with being cited in AI answers, and removing it from their model made the model more accurate. The authors say results are context-dependent and may change.
- Some AI labs publish one for their own docs. The proposal's site says OpenAI, Anthropic and Gemini publish llms.txt files for their developer documentation. That shows they publish the file. It does not say their products read other sites' files.
Some developer tools and agents will read it if you hand them the URL, which is why documentation-heavy sites adopt it first. That is a narrower benefit than "get cited by ChatGPT".
Do you need one?
- Probably worth an hour if you have a large site, a documentation section, or many product pages.
- Low priority if you have a small site with a handful of clear pages. Your time does better elsewhere.
- Never a substitute for the basics. A file that points to pages crawlers can't reach, or pages with vague copy, fixes nothing.
How to try it
- Pick five to ten pages that answer the questions buyers ask: product, pricing, FAQ, comparison, docs.
- Write a one-line description for each. Lead with what the page answers.
- Save the file as
llms.txtat your site root. Serve it as plain text. - Link to your canonical URLs only, not to redirects or tracking links.
- Update it when pages change, and add a reminder to review it each quarter.
It is not access control. Anything you list is public, and leaving a page out does not hide it.
What to do first
Two things matter more than this file. First, make sure the crawlers can reach your pages at all: Can AI crawlers read your site? Second, write pages an engine can quote: Write pages AI can quote
Not sure where you stand? The free AI Visibility Score scores what ChatGPT, Claude, and Perplexity say about you today.
Sources
Last checked October 18, 2026.