llms.txt is a plain-text Markdown file at the root of a website that summarises what the site is and links to its most useful pages, written for AI tools to read. It is a proposed convention, not a standard: Google has said it doesn't use it. It is cheap to add and can help AI tools and agents that do read it, but it is not a ranking lever.
Where llms.txt came from
llms.txt was proposed in September 2024 by Jeremy Howard of Answer.AI. The idea: websites are built for people and browsers, full of navigation, scripts and layout that a language model has to wade through. A short Markdown file at yoursite.com/llms.txt could give an AI tool the essentials in a form it reads easily.
What goes in the file
The proposed format is simple Markdown:
- An H1 with the name of the site or business.
- A short blockquote summarising what it is.
- Optional paragraphs with key facts or context.
- Sections of links to the most important pages, each with a one-line description.
For a business, the most useful content is the plain facts you want AI to get right: what you do and don't do, where you operate, who you serve, and how to describe you accurately.
What llms.txt does not do
- It isn't robots.txt. It doesn't allow or block crawlers. Access is still controlled in robots.txt.
- It isn't a Google ranking factor. Google has said publicly that it doesn't use llms.txt, and its guidance for AI Overviews requires no special files.
- It isn't guaranteed to be read. Support varies by AI company and tool, and changes over time. Treat it as a courtesy file, not a switch.
So is it worth adding?
Usually yes, for one practical reason: writing it forces you to decide, in a few sentences, exactly how you want AI to describe your business. That wording then belongs on your About page, your structured data and your profiles too, where it definitely gets read.
It costs an hour and carries no SEO risk. Just don't expect it to move rankings or citations on its own, and be wary of anyone selling it as the key to AI visibility.
A simple template
# Your Business Name · > One sentence: what you are, where, and for whom. · Key facts: founded year, locations, languages, what you do not offer. · ## Services: links to each service page with a one-line description. · ## About: links to About, team and contact pages.
Keep it short, factual and consistent with the rest of your site. If a fact in llms.txt contradicts your About page, you have made the AI's job harder, not easier.
Questions people ask
Does Google use llms.txt?
Google has said it doesn't. Its guidance for AI Overviews and AI Mode says no special files or markup are needed.
Is llms.txt the same as robots.txt?
No. robots.txt controls which crawlers may access your site. llms.txt is an optional summary for AI tools to read, and doesn't grant or block access.
Where should llms.txt go?
At the root of your domain, so it is available at yoursite.com/llms.txt, served as plain text.
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