What Is llms.txt and Do You Really Need One?
In short
llms.txt is a Markdown summary of your website, placed at its root, meant to help AI assistants find your most important pages. Proposed in 2024, it isn't a standard adopted by the major search engines, and Google says it doesn't need it. It's cheap to add, but it doesn't replace SEO or clear content.
Key takeaways
- llms.txt was proposed by Jeremy Howard (Answer.AI) on September 3, 2024, at llmstxt.org.
- It's a Markdown file at the root of your site: a title, a summary, then lists of annotated links.
- Google says no special 'AI text file' is needed to appear in its AI features.
- Agents and tools that read it can benefit, but no major engine has committed to using it for ranking or citations.
- Do it last, after crawler access, technical health and quotable content.
What is an llms.txt file?
An llms.txt file is a Markdown document placed at the root of a website that summarizes the site for large language models (LLMs). In a few lines, it says who you are and which pages to read first.
The idea was proposed by Jeremy Howard, co-founder of Answer.AI, on September 3, 2024, at llmstxt.org. The starting point: a modern web page is cluttered with menus, scripts and ads. An AI assistant that has to read your site within limited space wastes effort sorting through it.
So llms.txt acts as a clean table of contents, with no layout. Think of it as a sitemap, but written for an AI to read rather than an indexing crawler.
What does the llms.txt format look like?
An llms.txt file follows a simple Markdown structure with only one required element: a main heading with the site's name. Everything else is recommended but optional.
According to the official proposal, the file contains, in order:
- An H1 heading: the name of the project or site. This is the only required element.
- A blockquote summary: one or two sentences with the essentials.
- Free-text details: context, audience, how to interpret the content.
- H2 sections of links: each line is a Markdown link, optionally followed by a short note.
- An 'Optional' section: secondary links a tool can skip when space is tight.
The proposal also suggests offering a Markdown version of important pages at the same URL with a .md extension. That's a recommendation, not a requirement.
What does llms.txt do, and what doesn't it do?
llms.txt helps an AI tool that reads it understand your site faster, but it guarantees no visibility at all. Keep that distinction in mind before you spend time on it.
| What llms.txt can do | What llms.txt doesn't do |
|---|---|
| Give a reliable summary of your business | Improve your Google rankings |
| Point to your most useful pages | Allow or block a crawler (that's robots.txt) |
| Make life easier for an agent or developer tool | Force ChatGPT, Gemini or Perplexity to cite you |
| Clarify your services and contact details | Replace clear, indexable, up-to-date pages |
The public positions are clear. On its page about AI features in Search, Google writes that you don't need to create new machine-readable files or AI text files to appear in AI Overviews or AI Mode. Google's John Mueller has even compared llms.txt to the old meta keywords tag, according to Search Engine Journal.
On OpenAI's side, the crawler documentation doesn't mention llms.txt. For ChatGPT search, the documented lever remains access for OAI-SearchBot, which we cover in how to appear in ChatGPT.
That said, things are still moving. Search Engine Journal reported in May 2026 that Google's Lighthouse tool added an llms.txt check in an experimental category focused on agentic browsing, separate from SEO. In short: not needed for Google Search, but on the radar for agents.
Should you create an llms.txt anyway?
Yes, if your fundamentals are already solid, because it costs little and can help tools that read it. No, if you're counting on it to drive visibility in place of everything else.
Our recommendation, in order of priority:
- Open access to crawlers from search engines and AI (robots.txt, CDN, firewall).
- Fix the technical side: indexable pages, content present in the HTML, a fast site.
- Write quotable content: direct answer first, lists, tables, FAQs.
- Build your reputation: consistent mentions on trusted third-party sites.
- Add an llms.txt, ideally generated automatically so it stays current.
You'll find these steps, with the checks that go with them, in our GEO checklist.
What does an llms.txt look like in practice?
The easiest way to understand it is to look at a real one: Ozapp's is public at ozapp.io/llms.txt. It's generated automatically from the site's content, so nothing gets missed when a page is added.
Here's how it's structured:
- A heading: the agency's name and what it does.
- A summary: an AI-first agency in Belgium, its services and the site's languages.
- Services and guides in French, Dutch and English, with one link per page and a short description.
- Location pages and a section about the free AI demos.
- Company details and how pricing works (custom quotes).
- An 'Optional' section pointing to an llms-full.txt (the full text of the pages) and the sitemap.
The file is written in English, a common convention for this format, but it lists URLs in all three languages. For a multilingual Belgian site, that's a simple way to show the same offering exists in FR, NL and EN.
How can you tell if llms.txt is being read?
The only reliable measure is your server logs: they show which bots request the llms.txt file and how often. Without that data, there's no way to know whether it does anything for your site.
Don't confuse being read with having an effect. A bot downloading the file doesn't prove it shapes any answer. To measure what really matters, mentions and citations of your brand, see our method to measure your AI visibility.
Take the next step
Want to know whether AI engines already recommend your business, with or without llms.txt? Try the free demo on our AI demos page. For a full review and an action plan, explore our SEO & GEO service: free 30-minute consultation and a detailed quote within 24-48 hours.
Frequently asked questions
Does llms.txt improve Google rankings?
No. Google states in its documentation that you don't need to create new machine-readable files or AI text files to appear in AI Overviews or AI Mode. Standard SEO practices still apply. An llms.txt file therefore has no expected effect on how you rank in Google.
Where should the llms.txt file go?
At the root of your domain, like robots.txt: yoursite.com/llms.txt. According to the proposal on llmstxt.org, it's a Markdown file. You can write it by hand or have your website generate it automatically, which keeps it from going stale as you add pages.
What's the difference between llms.txt and robots.txt?
Robots.txt tells crawlers what they're allowed to access; llms.txt summarizes what's worth reading. The first is an established mechanism that major crawlers respect. The second is an optional proposal. llms.txt doesn't block or allow anything, so it never replaces your robots.txt.
Do I need an llms-full.txt as well?
It's not required. Some sites publish a second file containing the full text of their main pages, so an AI tool can read everything in a single request. It's useful for technical documentation or a well-structured services site. For a small business website, llms.txt on its own is plenty.
How much does it cost to set up llms.txt?
Very little. For a simple site, a few hours are enough to write the summary and list the key pages. On a modern site, it can be generated automatically from existing content. The real cost lies elsewhere: keeping your pages clear and up to date, since the file only points to them.
