What Is llms.txt, and Does Your Business Need One?
A sensible idea, an easy afternoon, and a much smaller payoff than the people selling it suggest.
What The File Is
llms.txt is a plain text file at the root of your site, at yoursite.com/llms.txt, written in Markdown. It describes what your site contains and points to the pages that matter, in a form that is easy for a language model to read.
The analogy people reach for is robots.txt, and it is close enough to be useful but wrong in an important way. robots.txt tells crawlers where they may not go. llms.txt tells AI systems what is worth reading and how your site is organized.
A typical file is short. A sentence about what the business does, then a linked list of key pages grouped under headings, each with a one-line description.
Where It Came From
The proposal came from Jeremy Howard in late 2024. The reasoning is straightforward. Language models work from a limited context window, and a modern website is mostly navigation, scripts and styling wrapped around a small amount of actual content. Handing a model a curated index is more efficient than making it parse your homepage.
It remains a proposal: no standards body has adopted it, and no major AI company has committed to honoring it.
That distinction matters, and it is the thing most enthusiastic write-ups skip past.
What It Is Not
It is not a ranking factor. Adding one will not get you cited, and no engine has said it will.
It does not control what AI systems say about you. Anything they can read on your public site remains readable regardless of what your llms.txt says.
Nor is it a substitute for having content worth citing. A beautifully organized index pointing at four thin pages is still four thin pages.
Blocking is a different job entirely. Restricting AI crawlers happens through robots.txt directives against specific user agents, which is a different file and a different decision.
Who Reads It Today
Here is the honest state of things as of this writing. Adoption on the publishing side has been reasonably brisk, particularly among developer tools and documentation sites. Adoption on the consuming side has not.
No major assistant has publicly confirmed that it reads llms.txt as part of normal retrieval. Some developer-facing tools and coding assistants do use it. General-purpose assistants answering a question about local plumbers almost certainly are not.
So the case for adding one is that it is cheap and low risk, and that it positions you if adoption arrives.
An Honest Assessment Of The Payoff
For a small business deciding where an afternoon goes, llms.txt is not the highest-value thing on the list. It is behind fixing your Google Business Profile, behind writing content that answers real customer questions, behind getting your service area into text, and behind cleaning up inconsistent listings.
It is cheap, though. For a small site it is a thirty-minute job, it cannot hurt you, and if the standard gains traction you are already there.
Treat it as housekeeping rather than strategy. Anyone charging you a meaningful amount to add one is charging for thirty minutes of Markdown.
If You Want One Anyway
Keep it to one screen. Open with an H1 that is your business name, then a blockquote of one or two sentences saying what you do and where. Then group your important pages under a few H2 headings with a one-line description each.
Point at the pages that answer questions and leave your privacy policy out. Services, pricing, service areas, your most substantial guides. If you have a lot of documentation, a second file at /llms-full.txt holding the expanded content is part of the proposal.
Then leave it alone until something changes. It needs no maintenance schedule and it will not show up in your traffic numbers. If someone tells you otherwise, ask them which engine confirmed it.