You may have heard you need to add a special little file to your website — a short summary that tells Ai tools who you are and what to read. It even has a techie name (llms.txt). Marketers are selling it hard. So does it actually work? Here's the honest answer.
The honest answer: there's no good evidence yet
Short version: As of 2026, the companies behind the big Ai tools haven't committed to using it.
The idea is reasonable — a tidy summary for machines to read. But reasonable isn't the same as proven. The major Ai providers have either said nothing about this file or said they don't use it, and there's no solid evidence it changes whether you get mentioned. We'd rather tell you that plainly than sell you a chore.
It's not that the file hurts. It's that it's unproven — and it's being sold as if it isn't.
What actually controls whether Ai sees you
Short version: The boring stuff that's genuinely established.
Three things matter far more, and they're real: making sure the Ai tools are allowed to read your site at all (see if Ai can't read your site), making sure Microsoft's Bing has your site on file (it's the back door into ChatGPT — see why ChatGPT runs through Bing), and being talked about by others in credible places. That last one does most of the work.
So should you add it?
Short version: If it's free and quick, sure — just don't expect it to move the needle.
Adding the file is low-cost, so there's no harm in having one. The mistake is treating it as the thing that gets you recommended, and skipping the moves that actually do. Spend your real effort on access, Bing, and being mentioned — not on a file with no track record.
Where this comes from: 2026 reference guides on how Ai tools handle these files, which find no confirmed effect on whether you're quoted. We word this as “unproven,” not “useless” — if that changes, we'll update this.