AI search
llms.txt: what it is and when it helps
llms.txt is a short Markdown file that points AI tools to the pages that matter on your site. It is cheap to publish and easy to overrate. Here is what it does, how to write one, and where it belongs in your priorities.
What is an llms.txt file?
Web pages are built for people. They wrap the useful part in menus, banners, scripts and cookie notices, and turning that back into clean text is slow and imprecise for a machine. The llms.txt proposal offers a shortcut: one small file, in Markdown, that tells an AI tool what the site is about and where the useful pages are.
The file sits at yoursite.com/llms.txt. The current version of the proposal also allows one at a subfolder, such as /docs/llms.txt, covering only the pages below it. It suggests offering clean Markdown copies of important pages at the same address with .md added, so a tool can read the page without the HTML around it.
It is a proposal, not a web standard. You can read the full format at llmstxt.org. Nobody is obliged to read it, and nobody is obliged to publish one.
How is it different from robots.txt and sitemap.xml?
The three files sit side by side at the root of a site and do different jobs.
| File | What it does | Who reads it |
|---|---|---|
| robots.txt | Says which crawlers may access which parts of the site | Search engines and the documented AI crawlers, such as OAI-SearchBot and GPTBot |
| sitemap.xml | Lists every page you want indexed, with no explanation | Search engines, to discover and recrawl pages |
| llms.txt | Summarises the site and points to the few pages that matter most | Some AI tools and coding agents, when they need information about a topic |
How to write an llms.txt for a business site
The format is plain Markdown in a fixed order. For a clinic, a shop or an agency, an hour is enough.
Start with your name
The first line is a title: a single # followed by your business name. It is the only part the proposal requires.
Add a one-line summary
Below it, a quote line starting with > that says what you do, for whom, where, and in which languages. Write it as you would want an assistant to repeat it.
Add the key facts
A few plain lines with no headings: address, opening hours, how to book, areas served, and anything you do not offer. Keep them identical to your site and your Google Business Profile.
List your important pages
Under headings starting with ##, such as Services, Locations or Prices, list one link per line in Markdown, each followed by a colon and a short note on what the page answers.
Put secondary links under Optional
A last section headed Optional holds pages a tool can skip when space is short, such as articles or careers.
Publish and test
Upload it as plain text, open yoursite.com/llms.txt to confirm it loads, then paste it into an assistant and ask questions about your business using only that file.
What would a clinic’s file contain?
Picture a dental clinic in a mid-sized city. Its title line is the clinic’s name. The summary line says it is a dental clinic offering implants, orthodontics and general care, with consultations in French and Arabic and booking online or by phone.
Then come four plain lines: the address, the opening days and hours, the phone number, and a note that it does not treat patients under a certain age, if that is the case. A Services section links to the implant, orthodontics and whitening pages, each with a note such as “who it suits, number of visits, what changes the price”. A Locations section links to the page for each branch. Optional links to the blog.
That is the whole file. Short is the point: the proposal expects the file itself to fit easily in a model’s context, with the detail behind the links.
Who actually reads llms.txt?
This is where to be careful. The proposal itself says llms.txt is used most heavily for software documentation, where coding agents follow it to find the right reference page. That use is real. Several website builders and SEO plugins now generate a file automatically, so you may already have one without knowing.
For ordinary business websites, the picture is thinner. AI companies publish llms.txt files for their own developer documentation, which shows they find the format useful for docs. It does not show that their assistants read your file when answering a question about you. OpenAI’s crawler documentation deals with robots.txt and does not ask for llms.txt. Google’s documentation on AI features says you do not need new machine-readable files or AI text files to appear in AI Overviews or AI Mode (Google Search Central).
One small sign of uptake: Chrome’s Lighthouse includes an optional check that your server does not return an error when llms.txt is requested. It does not judge the contents. In short, adoption by assistants is uneven and mostly unconfirmed, and anyone selling llms.txt as the key to AI visibility is overselling it.
When is it worth doing?
Do it when the basics are already in place and an hour is easy to find. It is most useful when your site has many pages and the important ones are hard to spot, when you publish documentation or technical guides, or when your platform generates the file for you and you only need to check it.
Do not do it first. If OAI-SearchBot or Googlebot cannot reach your pages, if your service pages bury the answer, or if your listings contradict each other, llms.txt fixes none of that. Our guide on appearing in ChatGPT answers covers the work that comes before it, and technical SEO covers the crawling side.
Frequently asked questions
Does Google use llms.txt?
Google’s documentation for its AI features says you do not need new machine-readable files or AI text files to appear in AI Overviews or AI Mode. Do not count on llms.txt for Google visibility. Normal SEO and clear pages are what its AI Overviews and AI Mode depend on.
Does ChatGPT read llms.txt?
OpenAI has not documented that ChatGPT reads llms.txt on business websites. Its crawler documentation covers robots.txt rules for OAI-SearchBot, GPTBot and ChatGPT-User. If ChatGPT is your goal, start with those crawlers.
Can llms.txt stop AI tools from using my content?
No. llms.txt is a guide to your content and grants or refuses nothing. To allow or block crawlers, use robots.txt, and your firewall where needed.
Should I create Markdown versions of all my pages?
The proposal suggests it, as a clean copy of each page at the same address with .md added. For a business site with a few dozen pages, the upkeep is rarely worth it. For technical documentation read by coding agents, it can be.
Can llms.txt hurt my SEO?
There is no known effect either way. It is a small text file that search engines may crawl like any other. Keep it accurate and it costs almost nothing. If you want help deciding where it fits, our GEO service covers it alongside the rest of the work.
Last updated · By the Napexy team