What is llms.txt, and do you actually need one?

llms.txt is a plain text file at the root of your site — yoursite.com/llms.txt — that describes your business in a form a language model can read without interpreting your design, your images or your marketing copy.

It’s a young convention, not a ratified standard. That’s worth saying up front, because the honest answer to “do I need one?” is: it’s cheap, it’s low-risk, and it removes guesswork that currently costs you.

Why a separate file at all

Your homepage is built for people. It has a hero image, a testimonial carousel, a sticky header, a cookie banner and maybe 40 words of actual substance. A model reading it has to work out which parts are navigation, which are decoration, and which are facts.

llms.txt skips that. It’s the same information with the packaging removed.

What goes in it

Keep it short and factual. For a local service business, that’s roughly:

# Ridgeline Roofing

> Residential roofing contractor serving Wake and Durham counties,
> North Carolina. Licensed and insured since 1998.

## Services
- Roof replacement (asphalt shingle, metal, tile)
- Storm and hail damage repair
- Gutter installation and repair
- Free inspections and estimates

## Service area
Raleigh, Durham, Cary, Apex, Morrisville, Wake Forest, Chapel Hill

## Hours
Monday-Friday 7:00-17:00. Emergency callout available 24/7.

## Contact
(919) 555-0142 · hello@ridgelineroofing.com

## Key pages
- [Services](https://ridgelineroofing.com/services)
- [Service area](https://ridgelineroofing.com/areas)
- [Get an estimate](https://ridgelineroofing.com/estimate)

That’s it. Markdown, no HTML, no styling, no cleverness.

The three rules that matter

Be specific. “Serving the greater metro area” tells a model nothing. List the towns. A model can match “Apex” to a user’s question; it cannot match a vibe.

Don’t oversell. This file is read by something that will state its contents as fact. If you claim 24/7 emergency service you don’t offer, an assistant will tell a customer at 2am that you do.

Keep it current. A stale llms.txt is worse than none — it’s confidently wrong. If your hours change, change the file.

What it doesn’t do

It won’t get you into an assistant’s answers by itself, and anyone who tells you otherwise is selling something. If your robots.txt blocks AI crawlers, they’ll never fetch your llms.txt either. If your site is otherwise unreadable, one good file doesn’t rescue it.

It’s one item on a list of about eighteen. A useful one, and among the easiest to get right — but one.

Is it worth doing?

Yes, on the cost side alone. It takes twenty minutes to write, it can’t break anything, and the downside if the convention never catches on is a small unused text file. Compared with almost any other marketing spend, that’s an easy call.

Want to know whether you have one — and what else you’re missing? Run the free scan.