No, most UK trade and local service businesses do not need an llms.txt file to be found in Google or by AI tools. Google says plainly that its Search, including its AI features, does not use these files, and ChatGPT and Perplexity point site owners to robots.txt, not llms.txt. An llms.txt file is cheap and harmless to add, but it will not win you a single job on its own. Your time is far better spent on your Google Business Profile, a crawlable website and pages that answer real customer questions.
What is an llms.txt file?
llms.txt is a plain text file, written in Markdown, that sits at the root of a website (for example, yoursite.co.uk/llms.txt). It gives a short summary of what the site is about and links to its most important pages, so that AI tools and agents can understand the site quickly.
It was put forward by Jeremy Howard in September 2024 and is described on llmstxt.org as “a proposal to standardise on using an /llms.txt file to provide information to help agents use a website”. The key word is proposal. It is not an official web standard in the way robots.txt and XML sitemaps are, and no search engine is obliged to read it.
What does Google say about llms.txt?
Google answered this directly in its guide to optimising for generative AI features on Google Search (last updated 10 July 2026). Under a section called “Mythbusting generative AI search: what you don’t need to do”, it says:
“You don’t need to create new machine readable files, AI text files, markup, or Markdown to appear in Google Search (including its generative AI capabilities), as Google Search itself doesn’t use them.”
The same guide adds that Google may crawl many kinds of files, but “this doesn’t mean that the file is treated in a special way”. It also says there is no need to chunk or rewrite content specially for AI.
So for Google Search, AI Overviews and AI Mode, an llms.txt file makes no difference either way.
Then why does Chrome’s Lighthouse check for it?
This is where the confusion comes from. Lighthouse, Google’s free website audit tool built into Chrome, added an “Agentic Browsing” category in 2026 that includes an llms.txt audit. Chrome’s documentation calls the file “an emerging convention” and says that without it, AI agents “may spend more time crawling the site to understand its high-level structure”.
Read the detail, though. If your site has no llms.txt, Lighthouse marks the audit as “Not Applicable”, because “providing the file is optional at the moment”. It is only flagged when a file is there but cannot be read properly, for example because the server returns an error. Search Engine Journal reported the mixed messages in May 2026: Chrome is preparing for AI agents that browse websites on someone’s behalf, while Google Search says the file plays no part in rankings or AI answers.
Do ChatGPT and Perplexity use llms.txt?
Both companies publish an llms.txt file for their own developer documentation. But for getting your business into their search answers, their crawler pages point somewhere else.
- ChatGPT: OpenAI’s crawler documentation says that sites opted out of OAI-SearchBot “will not be shown in ChatGPT search answers”, and recommends allowing OAI-SearchBot in your robots.txt file.
- Perplexity: Perplexity’s bots guide says: “To ensure your site appears in search results, we recommend allowing PerplexityBot in your site’s robots.txt file”.
When we checked both pages on 5 October 2026, neither said that their search features read llms.txt when deciding which businesses to show. The file that matters for both is robots.txt. If a developer or security plugin has blocked these crawlers, no llms.txt file will fix it.
What actually helps a local business get found by AI tools?
The same things that help people find you on Google. Google’s guide lists Google Business Profiles as one of the products that “can help your products and services to be visible in both AI responses and other Google Search results”.
- A complete Google Business Profile. Correct categories, services, service areas, opening hours, photos of real work and replies to your reviews. Our Leeds Trades Google Gap 2026 study found that nearly 6 in 10 Leeds trade listings (59.7%) have fewer than 10 Google reviews, and 1 in 5 has none (Unavoidable Marketing research, 2026). Thin profiles give AI tools very little to work with. Our free Google profile check shows where yours stands against the three firms above you.
- Let the right crawlers in. Check your robots.txt allows Googlebot, OAI-SearchBot and PerplexityBot. This takes two minutes and matters far more than llms.txt.
- Consistent business details everywhere. The same name, phone number and service area on your website, profile and directories. We cover this in our guide to getting your business named by ChatGPT.
- Pages that answer real questions. A page for each main service and area, with prices or price ranges where you can give them, what is included and how quickly you can attend. See how to rank in Google AI Overviews as a local business.
Should a trade business create an llms.txt file anyway?
If your website is already in good shape, adding one does no harm. We publish one on unavoidablem.com because it takes a few minutes and gives AI agents a clean summary of what we do. We do not expect it to bring in work, and you should not either.
| Your situation | Our view |
|---|---|
| Profile incomplete, few service pages | Skip llms.txt for now. Fix the profile and website first. |
| Solid profile and website, want to be tidy | Fine to add one. Spend no more than half an hour on it. |
| Someone is charging you to “optimise for AI” with llms.txt | Ask what else is included. On its own, it is not worth paying for. |
What goes in an llms.txt file?
Keep it short, following the llmstxt.org format:
- A heading with your business name.
- One or two sentences on what you do and where you work.
- Links to your key pages: services, areas covered, prices, contact.
- Facts that match your website and Google profile exactly, with nothing that is out of date.
The last point matters most. An llms.txt file with old prices or a retired phone number is worse than none, because it gives AI tools conflicting facts about your business.
Frequently asked questions
Will an llms.txt file help me rank in Google?
No. Google’s own guidance says Google Search does not use these files, including for AI Overviews and AI Mode.
Can an llms.txt file hurt my rankings?
Google says such files get no special treatment, so there is no ranking penalty. The real risk is publishing out-of-date details.
Is llms.txt the same as robots.txt?
No. robots.txt tells crawlers what they may and may not access, and ChatGPT and Perplexity both rely on it. llms.txt is an optional summary that some AI tools and agents may read.
How can I tell if AI tools are already sending me visitors?
You can measure it in Google Analytics. Our guide to tracking AI referral traffic in GA4 shows how to set it up.
Want to know what is really holding you back?
If you are not sure why ChatGPT, Google or your customers are not finding you, an llms.txt file is not the answer. Book a free 30-minute strategy call and we will look at your profile, website and crawler settings with you and tell you plainly where to focus first.
Let’s make you Unavoidable.
About the author: Andrew Heppinstall is the founder of Unavoidable Marketing, a Leeds agency that helps UK trades and local service businesses win work through Google Local Services Ads, SEO and paid search. His article “What makes Google ads effective?” appeared on the Business Matters page of PHAM News in September 2026.