llms.txt: what it is, what it is not, and how to write one
llms.txt is a short Markdown file at the root of a site that points language models at the pages that matter. It is cheap, low-risk and useful as a clear summary. It is not a ranking factor, and nobody should sell it as one.
What it is
The convention was proposed in September 2024 by Jeremy Howard of Answer.AI. The file lives at /llms.txt and has a simple shape: a # title with the company or product name, a > blockquote summary of a sentence or two, then ## sections with links to the important pages, each with a short description.
It is a curated map, written for a reader with limited attention. A sitemap lists everything; llms.txt chooses.
What it is not
It is a young convention, not a standard that every assistant has committed to read. It does not improve rankings in search engines, and Google's own guidance from May 2026 says it is not needed for Google Search. Treat it as clarity for any model or agent that does look for it, and as a useful exercise for your own messaging: if you cannot summarize the company and choose its ten most important pages, a model cannot either.
How common it is in B2B software
Among the 274 B2B software companies in our study, 61% publish an llms.txt. Of the files we could grade, 95 out of 152 passed every check. The failures cluster in three places: files too long to be useful (a sitemap with a different extension), no summary at the top, and links that leave the company's own domain.
How to write a good one
# Acme
> Acme is a lead routing tool for B2B sales teams on Salesforce. It assigns every inbound lead to the right rep within a minute.
## Product
- [How routing works](https://www.acme.com/product): rules, round robin and account matching
- [Pricing](https://www.acme.com/pricing): plans and what each includes
## Help
- [Setup guide](https://www.acme.com/docs/setup): connect Salesforce in ten minutesThe seven checks we use: a # title, a > summary, at least three links to key pages, links mostly on your own domain, ## sections, enough substance to be useful, and under 30 KB. Keep it to the pages a buyer or an agent would actually want, and update it when those pages change.
Use the free llms.txt generator and grader: paste your domain to draft a file, or grade the one you have against the seven checks.
Check yourself
0 / 3Does publishing an llms.txt improve your rankings in Google Search?
It is useful clarity for models and agents that read it, not a search ranking lever.
What was the most common problem with the llms.txt files in our study?
A file that lists every page is a sitemap with a different extension.
What belongs at the very top of an llms.txt?
The title and summary are what a model can quote as they stand.