Not yet, in the sense most people mean. llms.txt is a proposed convention for a Markdown file describing your site to language models, and no major engine has confirmed it as a ranking or retrieval input. There is currently no published evidence that adding one changes what any of the six engines say about you. It is cheap, harmless and possibly forward-looking, but a vendor implying it will improve your AI visibility today is overselling a proposal as a standard. Treat it as a low-cost bet, not as a fix, and do not let it displace work that is known to matter.
Why this happens
The confusion comes from the analogy to robots.txt, which is a genuine, honoured standard. llms.txt borrows the shape and the naming, which makes it feel established. Adoption by publishers is not the same as adoption by engines, and only the second one would make it work.
It persists as advice because it is satisfying: a single file, quickly added, that feels like an action. That is precisely the kind of task that displaces slower work with real evidence behind it.
It is also worth separating two claims that get bundled together. “Engines can read a Markdown summary of your site” is plausible and uncontroversial. “Engines currently look for a file at /llms.txt and weight it” is the part with no evidence behind it. Vendors tend to assert the first and let readers infer the second. If you are being sold an llms.txt feature, the question worth asking is which engine has confirmed it reads the file: and the honest answer today, from every vendor including us, is none of them.
What to do about it
Add one if you want: it costs an hour and carries no downside.
Do not report it as an AI-visibility improvement, and do not let it substitute for crawler access, corroboration or presence on cited surfaces.
Re-check the position periodically; if an engine does adopt it, that will be announced rather than inferred.
Where Cituna fits
Cituna publishes a free llms.txt generator with no signup, and does not claim it moves your visibility, because no engine has said it reads the file. What the product actually measures is presence across the six engines daily from $39, which is a claim we can show you the evidence for.
Drafted with AI assistance from our own research and Search Console data, and reviewed by Rahul A before publishing. Rules and prices change; check the linked official source before you act.