Does llms.txt work?
llms.txt is an unproven community proposal. No major AI provider has publicly confirmed using it, and Google says you do not need new machine-readable files or AI text files to appear in its AI features. It is low-cost to publish, mainly useful for documentation read by coding agents.
What is llms.txt?
A markdown file at /llms.txt that lists a site’s key pages with short descriptions, intended to help language models find important content. It has no formal standards-body process.
What is the evidence?
- Proven Google’s AI features guidance says you do not need new machine readable files, AI text files or markup.
- Experimental Third-party log analyses report that major AI crawlers rarely request the file. We have not verified this ourselves.
- Practice Coding assistants and developer tools are reported to look for the file when pointed at documentation sites.
Who publishes one?
On 22 October 2026 eight of 15 sites we checked published llms.txt, including Semrush, Yoast, Cloudflare, Vercel and Stripe. Google and OpenAI did not. Adoption is not proof of benefit.
Should you add one?
If it takes minutes and you will keep it accurate, it does no harm. Do not expect ranking or citation gains. We publish ours as a labelled experiment.