What Is llms.txt and How Do You Write One? (With Example)

llms.txt is a plain-text file placed at the root of a website that summarises, in ordinary language, what the site is and which of its pages matter — written for AI models rather than people.

Where robots.txt is the "where are you allowed to go" file, llms.txt is the "here is what exists and what you should read" file.

Why it exists

A modern website is a noisy place for a language model: menus, cookie banners, scripts, repeated blocks. The model has to work out what the business actually does from all that, and sometimes it cannot.

llms.txt short-circuits the problem. A summary of the site and a list of its most important pages, in one plain-text file, written in human language.

Does it actually work? An honest answer

There are overblown claims about this file, so let us be precise:

• llms.txt is not an official standard. No engine has promised to read it.
• Adding it will not make ChatGPT recommend you tomorrow.
• But it costs almost nothing, it does no harm, and the exercise of writing a clear description of your site is useful on its own — that description is usually missing from the site itself too.

So: not a magic wand, but a cheap and sensible piece of hygiene. It is a complement to the visibility work, not its foundation. The heavy lifting is done by readable content and third-party mentions.

Where does it go?

At the root of your site, reachable at exactly this address:

https://yoursite.com/llms.txt

It must be served as plain text (text/plain or text/markdown). A common mistake: single-page apps return the homepage HTML for any unknown path. The file then looks like it exists, but contains HTML and is useless. Open it in a browser and confirm you see plain text with your own eyes.

What goes in it?

The structure is simple: a heading, a summary, then sections of important links.

# Northside Dental Practice

> A private dental practice in Leeds offering implants, orthodontics and
> cosmetic dentistry, in operation since 2011.

## Services
- [Dental implants](https://example.com/implants): Single-tooth and full-arch implant treatment.
- [Orthodontics](https://example.com/orthodontics): Clear aligners and fixed braces.
- [Teeth whitening](https://example.com/whitening): In-practice and take-home whitening.

## About
- [About us](https://example.com/about): The team, practice history and equipment.
- [Contact](https://example.com/contact): Address, phone, opening hours.

## Details
- Address: Leeds, United Kingdom
- Opening hours: Monday-Saturday 09:00-19:00

Rules for a good llms.txt

1. Write in human language. Proper sentences, not a pile of keywords. The thing reading this understands language; it is not counting words.

2. Finish the summary in the first paragraph. Who you are, where you are, what you do — answered in the first three lines. If a model quotes you, it quotes from there.

3. Give every link one sentence of description. A bare list of links forces the reader to go and look. An annotated list gives information.

4. Do not overclaim. "The best in the country" earns no trust because it cannot be verified. Verifiable detail does: year founded, location, service list.

5. Keep it current. A closed branch or a service you no longer offer becomes misinformation in circulation.

6. Keep it short. One or two pages is plenty. It does not need to be a copy of the site — it needs to be a map of it.

How to generate one

You can write it by hand; the template is above. If you would rather go faster, the llms.txt generator produces a ready-made file from your site's address — free, no signup.

Once generated, upload it to the root of your site and open yoursite.com/llms.txt in a browser to confirm it really renders as plain text.

What comes next

llms.txt is not a visibility strategy on its own. Put it in this order:

1. Confirm AI crawlers can read your site (checker).
2. Make sure your pages contain genuinely readable text.
3. Declare who you are with structured data.
4. Add the llms.txt summary layer.
5. Measure — and re-measure as you fix things.

llms.txt is not a magic file. But if you cannot describe your site in two paragraphs, the problem was never the file — and it is worth something just for making that obvious.