The file might matter for AI agents one day, but right now that is speculative. So if an SEO tool is flashing a red warning about your missing llms.txt, you can relax and spend that time on something that actually moves the needle.
What an llms.txt file even is
An llms.txt file is a plain text or markdown file placed at the root of your domain. The idea is to give large language models a tidy summary of your site, its structure, and your most important content, so an AI does not have to wade through your HTML to work you out. It is a sensible-sounding proposal. The trouble is that it remains exactly that, a proposal, with no formal standard behind it and very little adoption.
If you want the wider context for how AI is reshaping search, our guide to SEO for AI Overviews is a good place to start before you worry about any single file.
What Google actually said
Google’s position has not wavered. Its June guidance for marketers, alongside an earlier technical guide, named llms.txt directly as a tactic that does not help with AI search features. John Mueller of Google’s Search Relations team went further on a public forum, calling the file purely speculative and noting that it has existed for years while no AI system actually reads it. He compared it to the old keywords meta tag, a self-declared signal that was easy to game and long ago abandoned.
The confusion that sparked the June questions came from Chrome’s Lighthouse tool, which added a check for an llms.txt file in its agentic browsing audits. Mueller drew a clear line. That check is about helping an agent complete a task once it is already on your site, not about being discovered in search. As he put it, it is not done for search. For ranking and visibility, the file does nothing.
| Tactic | Does it help Google’s AI search features? |
|---|---|
| Helpful, original content that answers real intent | Yes |
| Clean crawlability and indexing | Yes |
| Structured data so Google can parse your entities | Yes |
| Not blocking AI and agent crawlers | Yes |
| An llms.txt file | No, not used by Google Search |
| Separate markdown pages built for AI crawlers | No, actively discouraged |
Why the panic spread in the first place
Picture a marketing manager at a UK software firm. An audit tool flags a missing llms.txt as a critical issue, the dashboard turns red, and suddenly it feels urgent. Then a plugin appears offering to generate one in seconds. That loop, where tools create the worry and then sell the cure, is a big reason this file feels more important than it is. Independent research backs up the calm view, with one analysis finding no clear link between having an llms.txt file and how often a site gets cited by AI. There are almost always bigger wins waiting, like fixing crawl budget or tightening your structured data.
What to do instead
Put your effort where Google is actually looking. That means original content with a real point of view, clean technical foundations, and markup that helps machines understand who you are. A proper site audit will tell you whether AI crawlers can even reach your pages, which Mueller says is the more pressing question for most sites than any AI file. Strong technical SEO agency work and an entity-first approach will do far more for your AI visibility than a curated text file ever could.
This is also where treating AI search as a discipline pays off. Our work on generative engine optimisation and our notes on generative engine optimisation for UK brands focus on the signals that genuinely influence citations. None of it relies on llms.txt. If you want a sense check on your wider plan, the SEO strategy for 2026 piece sets out the priorities. You can read Search Engine Land’s coverage of the Lighthouse clarification if you want the detail straight from the source.
So should you ever bother?
There is one sensible exception. If an AI platform that genuinely sends you customers tells you it needs the file, then create one. It costs little and does no harm. Outside that, treat llms.txt as optional housekeeping rather than a priority. Mueller’s own advice is roughly that. Build the file when a platform that brings you business actually asks for it, and not before.
Frequently asked questions
What is an llms.txt file?
It is a markdown file placed at the root of your domain that summarises your site’s structure and key content for AI models. It is a proposed format, not an official standard.
Does Google use llms.txt?
No. Google has confirmed that Search does not use llms.txt and it is not a ranking or visibility signal.
Will an llms.txt file help me appear in AI Overviews?
No. AI Overviews and AI Mode draw on the same fundamentals as normal search, so helpful content and clean technical SEO matter far more.
Should I add an llms.txt file anyway?
Only if an AI platform that sends you real customers asks for it. For most UK businesses it is optional and not worth prioritising.
Want to focus on what actually works?
Skip the hype and put your budget where it counts. Speak to our agency and we will show you the technical and content signals that genuinely shape your AI search visibility, from crawlability to SEO services and, where it fits, paid search to capture demand while the AI landscape settles. Book a free consultation and build on solid ground.