llms.txt: what it's for, and should you add one

For a few months now, we keep hearing the same question: "apparently every website needs an llms.txt file, is that true?". The short answer: it takes an hour, it can't hurt, and you shouldn't expect anything spectacular from it. The long answer is this article.

A text file at the root of your website

An llms.txt is a plain text file placed at the root of a website, like the robots.txt that search engines have been reading for twenty years. You can look at ours: it lives at dorima.fr/llms.txt.

Its purpose is to introduce your website to a machine, clearly and without decoration: who you are, what you do, which pages matter and what they contain. A human visitor understands your business by looking at your homepage; an AI has to infer it from your code, your menus and your images. The llms.txt spares it that guesswork.

The format is deliberately minimal: text, a few headings, a list of annotated links.

# Dorima
 
> French agency building custom web software: business applications,
> SaaS, dashboards and artificial intelligence integration.
 
## Services
 
- [Web development](https://dorima.fr/en/services/web-development): business
  applications, custom software, taking over existing code.
- [Artificial intelligence](https://dorima.fr/en/services/artificial-intelligence):
  AI inside your tools, document management.

That's it. No complex markup, no technical format to follow to the letter.

Where llms.txt comes from

The idea was proposed in late 2024 by Jeremy Howard, a well-known researcher in the AI world. The reasoning was simple: language models have a limited reading capacity, they struggle with modern web pages full of scripts and menus, so why not hand them the essentials directly.

The proposal spread fast. Many technical websites added one, generators appeared, and the topic became a sales pitch for quite a few agencies.

What it really changes

This is where honesty matters, and it's the heart of the article.

None of the major AI providers has officially announced that they use this file. Not OpenAI, not Google, not Anthropic. As of today, it's a convention proposed by the community, adopted by part of the web, but nothing like a recognised standard. Anyone promising you a measurable effect on your ChatGPT citations because they added an llms.txt is selling you thin air.

What the file actually brings is something else:

• It costs almost nothing. An hour of work, no heavy maintenance, no technical risk.
• Smaller tools may read it. Internal assistants, agents, alternative search engines: all of them look for clean sources to digest.
• It forces you to describe what you do on one page. Oddly, that's its most concrete benefit. Summing up your business in fifteen readable lines is a useful exercise, and many websites can't do it.

In other words: it's a low-cost bet, not a search optimisation technique.

What it doesn't replace

An llms.txt will never make up for a website that machines can't read. If your content only appears once a script has run, if your services are described inside an image, if your pages take eight seconds to load on a phone, the file changes nothing: it will point to unusable pages.

The order of priorities never changes. First, a website that machines read effortlessly. Then, pages that genuinely answer your customers' questions. The llms.txt comes last, as a courtesy to robots, not as a solution.

Should you add one? Our position

Yes, if these three conditions are met:

1. Your website is already readable and fast. If not, start there.
2. Someone can keep the file up to date. An llms.txt describing a service you dropped two years ago is worse than no file at all.
3. You write it yourself, or your provider includes it in broader work. Paying for a dedicated service for fifteen lines of text makes no sense.

No, if it's sold to you as a visibility lever on its own. In that case, ask one simple question: "which official source shows that it works?". The answer is usually telling.

How to write yours

If you go ahead, here is the structure that works well:

• A heading with your company name.
• A one-sentence summary, preceded by >: what you do, for whom, where. It's the most important line in the file, so write it as if you were answering someone who has never heard of you.
• Sections by main topic: services, references, contact.
• Annotated links: the page address, then one line saying what's on it.

Two classic mistakes to avoid. The first is copying marketing slogans: "excellence serving your performance" tells a machine nothing, nor a human for that matter. The second is listing everything: ten well-chosen links beat a hundred.

Then place the file at the root of your website, at yourwebsite.com/llms.txt, and check that it shows up as plain text in a browser.

In short

The llms.txt is a cheap good practice, and a poor sales argument. Add one if your website is already in order, and judge those who charge a lot for it.

If you'd like to know where your website stands from an AI's point of view (what it reads, what blocks it, what it answers when asked about your trade), get in touch: we'll take a look.