llms.txt
A text file at the root of your site telling AI models what is on each page, one line per page.
A sitemap lists addresses and nothing else. llms.txt says what each one is about, which is what makes a model cite the right page instead of your home page.
It is not an official standard and not every model reads it yet. It costs little to add and does no harm, so the ratio of cost to possible payoff is good.
The important part is that it comes out of the site's real content. A handwritten llms.txt goes stale in a month and then points models at pages that no longer exist.
What to do about it
Type yourdomain.com/llms.txt into a browser. If it errors, ask whoever handles your site whether it can be generated.
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