llms.txt: what is it, and does your business need one?

If you have heard of llms.txt and wondered whether it is just another SEO trend to jump on, the answer is a bit more nuanced than yes or no. Here is what the file actually is, what it is not, and how to judge whether it is worth the time for your business.

What llms.txt is

llms.txt is a simple, proposed standard (launched by developer Jeremy Howard in 2024) for a Markdown file that sits at the root of a website, the same way robots.txt or sitemap.xml does. The file gives a short overview of the website and links to the pages that matter most to understand, typically documentation, product pages or core content, written in a format that is easier for a language model to parse than a full HTML page full of navigation, ads and scripts.

What it is not

It is important to be honest about the limitations. llms.txt is not an official standard that has been adopted or guaranteed to be supported by OpenAI, Anthropic or Google. There is no confirmation from any of the major providers that their models actively read and prioritize the file during normal use. Some tools and crawlers support it, others ignore it entirely. Treat it as an aid you can offer, not as a guaranteed channel into a model's answer.

robots.txt, sitemap.xml and llms.txt: what is the difference?

• robots.txt tells crawlers what they are allowed to visit, in other words access control.
• sitemap.xml lists every page on the website, primarily for search engine indexing.
• llms.txt summarizes what matters most to read and understand, written for a language model rather than a traditional crawler.

So they solve three different problems, and they do not exclude each other. Most websites should have robots.txt and sitemap.xml in place regardless. llms.txt is a third, optional layer.

Does your business need one?

It depends on how much and how complex your content is. A small website with a handful of pages has little to gain from a dedicated llms.txt, since there is not much to choose between anyway. The benefit grows the more content you have: documentation, a large product catalog, an extensive knowledge base or an active blog. In that case, an llms.txt can act as a roadmap that points a model directly to the pages that actually answer a question, instead of having it guess its way through the entire website.

How to create one

The file is plain Markdown and needs neither build tools nor special technical skills. A simple structure is:

• An H1 with the name of the business or product.
• A short paragraph summarizing what you do.
• One or more sections (H2) with links to the most important pages, with a short explanation of what each link contains.

Put the file at the root of the website, meaning it should be available as /llms.txt. Keep it updated as you publish new core content, otherwise it points to outdated information, which is worse than having no file at all.

The bottom line

Think of llms.txt as low-hanging fruit, not as your main strategy. It costs almost nothing to set up, cannot hurt you, and provides a marginal benefit with the tools that support it. But it does not replace what actually determines visibility: consistent facts, concrete content and credible third-party mentions. We go through those measures in How to make your business visible in ChatGPT, Claude, Gemini and Perplexity.