What it is
In plain words, before anything else.
Assistants reading a website have to work out what the business is from whatever the site happens to say. llms.txt is a convention for skipping the guesswork: a single file at yourdomain.com/llms.txt, written in plain words, that states what you do and points at the pages that matter.
It is not a standard anybody enforces and nothing breaks without it. It is closer to the sign in the window than to plumbing. The reason it earns its place is that it is the cheapest way to control what a machine says about you rather than leaving it to inference.
What it costs you
The loss you never see happen.
Without one, an assistant summarising your business works from your homepage copy, which was written to move a human reader rather than to state facts. The summary it produces is the one your customer hears, and you never see it.
The specific loss is nuance. A one location salon that also does bridal work reads, to a machine, as a salon. The bridal enquiry goes elsewhere.
Check it yourself
Do not take our word for it. Look.
This takes about a minute, costs nothing, and needs no account with us or anybody else. A finding you have confirmed with your own eyes is the only kind worth acting on.
- 1
Type yourdomain.com/llms.txt into a browser.
- 2
If you see plain text describing your business, you have one. If you get a not found page, you do not.
- 3
If you get your normal website with its menu and pictures, that is a miss too: the file has to be plain text, not a web page.
What we found
Out of 186 businesses we checked ourselves.
- 150 of 186
had no llms.txt at all. Thirty six had one, and nearly all of those got it from their website builder rather than by choosing it.
Counted from our own checks of 186 real businesses, measured on 2026-09-10, one count per business. No business is named and none of their reports is public. The full write ups are in what we found.
How we fix it
What we do, and what we leave alone.
We write yours from what is already on your site and host it, and we keep it current as your services change. You read it before it goes up and you can change any line of it.
Nothing is invented. If a fact is not on your site or confirmed by you, it does not go in the file.
Next
The checks closest to this one.
- L1
Can an AI assistant actually read your website?
A site that needs a full browser to show anything is invisible to most of the software now answering questions about businesses like yours. - L3
Your hours and services, in a form a machine understands
A hidden block on the page that states your address, your hours and what you sell as facts, not as words on a picture. - L7
A way to reach you that does not need somebody to answer
An assistant acting for a customer needs a way in it can actually use. A number printed on a picture is not one.
Is this one open on your site?
The free check runs all sixteen against your own address and tells you which came back clean, in the same plain words as this page.
Free. No signup. Takes about a minute.