llms.txt is the map of your site written for assistants rather than people. Nobody ever opens that URL, so it is written once and then quietly rots: pages get renamed, sections disappear, and the only reader who notices is a machine that cannot tell you.
Public files only. The address you type is not stored.
No file yet? The free llms.txt generator builds a draft from your own pages.
Each line of the result comes from one of these tests. Red stops a reader, amber costs it time, green is fine.
| Test | Passes when | Fails when |
|---|---|---|
| The file is there | /llms.txt answers with a file | 404, a server error, or no answer at all |
| Heading | The first line is # Your name | No H1: a reader cannot tell whose map it is |
| Summary | A > line sits under the heading | Missing (amber): nothing for an assistant to quote about you |
| Sections | ## headings group the links | Missing (amber): one long undivided list |
| Link format | Links read [title](address) | Bare addresses (amber), or no links at all (red) |
| Links lead somewhere | Up to twelve links followed, each answers 200 | A 404 or no answer (red); a redirect (amber) |
| Links stay on your site | The map points at your own pages | Links to other domains (amber) |
| llms-full.txt | Optional; noted when present | Never counted against you |
# Isla Verde Property > Independent buyer guides for Isla Verde: what condos cost by district, the fees at completion, the title checks that matter. ## Buyer guides - [Fees and taxes at completion](https://example.com/guides/fees-and-taxes-at-completion/): every fee a buyer pays, with worked examples at three prices - [Service charges in condo buildings](https://example.com/guides/service-charges/): what the monthly charge covers and how it is set
One H1 naming the site. One blockquote saying what it is. Sections of links, each with a line explaining what the reader will find. Nothing else is required, and nothing else is read.
A file like this one is common: written by hand a year ago, never opened since.
Our company https://example.com/services/ https://example.com/old-pricing/
The addresses are there, but not as list items: the format wants each one on its own - [title](address): note line, so a reader finds nothing it recognises as a link. Fix the shape, then run the check again to see where each link leads.
About half the sites we checked already publish one: in our study of 731 websites, 49% of English-language sites (84 of 172) had an llms.txt.
Having it did not make ChatGPT name a business more often: 32% of sites with the file were named, against 36% without it. Validate it so it does no harm, but do not expect it to win you a mention on its own.
This reads one file. The free OperStack check reads the whole site the way a search engine and an AI read it, scores five areas in about a minute, and asks ChatGPT the questions your buyers ask to see whether it names you.
A plain text file at the root of a site, /llms.txt, that lists the pages worth reading with one line each. It is a map written for programs: an assistant reads it instead of crawling the whole site, and decides from it what you have. The format asks for one heading naming the site, a short summary, and sections of links.
Not for Google rankings. It matters to assistants that fetch a site to answer a question: with a map they read the right pages, without one they read whatever the HTML gives them and often quote the wrong thing. No engine has promised to honour it, and anyone who tells you otherwise is selling something.
Because nobody ever opens that URL. The file is written once and the site keeps moving: pages get renamed, sections disappear. Six months later half the map leads nowhere and the only reader affected is a machine that cannot complain.
Whether the file exists, whether it starts with a heading as the format asks, whether it carries a summary and sections, how many links it lists, and where up to twelve of those links actually lead: a page, a redirect, or nothing. It also looks for llms-full.txt beside it.
No. The check runs while the page loads and nothing is written down. There is no account and no cookie for it.
Generate it from your own content rather than by hand, so it cannot drift. The free OperStack Astro starter builds llms.txt and llms-full.txt from the corpus on every build, which is why its map cannot go stale. Any generator that reads your sitemap will do the same job, including our free llms.txt generator.
Built by Maksim Shchegolev, founder of OperStack. Free, no account, no cookie. The address you check is not stored.
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