llms.txt checker: does my site need one?

WebAISEO: free AI-search check Prices WebAISEO Terms For AI agents

Published 11 November 2026 · by TrueTest

llms.txt is a plain-text file at the root of a site (/llms.txt) that summarises the site for AI tools: what it is, and links to its key pages in Markdown. It is a proposal, not a standard. Major AI search engines have not confirmed that they use it, so our check gives it a low weight and labels it "emerging". It is cheap to add, and some AI tools and agents do read it.

Check my llms.txt free See a full example first

Type your address into the box at the top of the WebAISEO page: the Readiness basics check reads one public page and its robots.txt, sitemap and llms.txt, takes a few seconds, needs no sign-up and is free. The paid audits are described on the WebAISEO page.

What does a good llms.txt look like?

Ours is live at truetest.uk/llms.txt. Its shape:

# EA Trade Tester by TrueTest

> One-sentence summary of what the site does.

A short paragraph: what you do, for whom, what is free.

## Pages
- [Page name](https://example.com/page): what is on it
- [Another page](https://example.com/other): what is on it

## Prices
- the real prices, the same as on the site

What does the free check test?

the file answers at /llms.txt with 200;
it has more than a few characters of content;
it is text, not an HTML error page served under that name (a common fault: the site's 404 page returns 200).

A missing llms.txt is a "warn", never a "fail", and it is 2 points of the 15 in the discoverability area.

What should I not put in it?

Claims that the pages do not make: the file should agree with the site.
Prices or terms that differ from the pages.
Private addresses: everything in it is public.

Is llms.txt the same as robots.txt?

No. robots.txt says which crawlers may read which addresses, and crawlers obey it. llms.txt only describes the site; it allows or blocks nothing. If robots.txt blocks a crawler, a good llms.txt does not help (robots.txt checker).

More guides: AI search readiness score explained · Can AI crawlers read my JavaScript site? · Do noindex or nosnippet block AI answers? · AI readiness check as an MCP tool · Headings that AI answers can lift · Author, dates and trust signals · Sitemaps, HTTPS and speed for AI crawlers · AI search optimisation vs classic SEO

Questions people ask

Do ChatGPT or Google use llms.txt?

Neither has confirmed it. Treat it as an optional extra for AI tools and agents that do read it.

Where does the file go?

At the root of the site: https://yoursite.com/llms.txt, served as plain text.

Should I add llms-full.txt?

Some sites add a longer version with the full text. It is optional too; keep it in step with the pages.

Can the check write one for me?

The free check tells you whether yours is there and readable. The paid audit's Fix Kit includes suggested files.