What is llms.txt, and do you need one?
llms.txt is a proposed standard for handing language models a clean map of your site. It is cheap to add and easy to misunderstand, so here is the honest version: what it is, how it differs from robots.txt, and whether it is worth your afternoon.
The idea in plain terms
A normal web page is built for people. It carries navigation, banners, related links and styling that a language model has to wade through to reach the substance. The llms.txt proposal, put forward in 2024, suggests placing a single markdown file at /llms.txt that lists your most important pages with short descriptions, in a format that is trivial for a model to parse. Think of it as a curated table of contents written for machines.
How it differs from robots.txt
The two are often confused because the names rhyme, but they do opposite jobs. robots.txt is a gate: it tells crawlers what they are allowed to touch, and it is a long-established standard that engines respect. llms.txt is an invitation: it proactively points models at your best content. One controls access, the other offers a guide. You can and often should have both.
The honest state of adoption
This is where realism matters. llms.txt has been adopted by a number of documentation sites and developer tools, and there are libraries that generate it automatically. But the major answer engines have not officially committed to reading it, and there is little hard evidence yet that having one changes whether you get cited. Anyone promising that an llms.txt file will lift your AI visibility is overstating what is known.
So should you add one?
For most sites, adding a well-made llms.txt is reasonable low-cost insurance. It takes little effort, it does no harm, and if adoption grows you are already prepared. What it is not is a substitute for the fundamentals. A clean llms.txt on a site that blocks AI crawlers or carries no structured data helps no one.
Put your effort where the evidence is first: crawler access, structured data and direct answers. The free Avantas audit scores those in about fifteen seconds. Then, if you like, add an llms.txt as a finishing touch. For the groundwork, see structured data for AI and what AEO means.
Common questions
What is llms.txt?
llms.txt is a proposed convention: a markdown file at the root of your site that gives language models a concise, curated guide to your most important content. It was suggested in 2024 as a way to help AI tools find the signal on a site without wading through navigation and boilerplate.
Is llms.txt the same as robots.txt?
No. robots.txt tells crawlers what they may and may not access, and it is widely honoured. llms.txt is the opposite in spirit: it proactively points models at your best content in a clean format. robots.txt controls access, llms.txt offers a curated map.
Do the major AI engines actually use llms.txt?
Not in any confirmed, official way as things stand. It is a community proposal that some tools and documentation sites have adopted, but the large answer engines have not committed to consuming it. Treat it as low-cost insurance, not a proven ranking lever.