llms.txt is a plain text file that sits at the root of your website and gives AI systems a short, curated guide to what your business is and which pages matter most. For most local businesses the answer to "should we have one?" is yes. It takes under an hour and has no real downside, so it's cheap insurance in case the engines that read it keep gaining ground.
Why does llms.txt exist?
The proposal starts from the fact that web pages are built for browsers rather than language models. A typical homepage is a pile of navigation menus, scripts, cookie banners, and layout markup wrapped around a modest amount of useful information. People skip past all that without thinking, but an AI system has to spend limited context on it and doesn't always find the parts that matter.
llms.txt, proposed by technologist Jeremy Howard in 2024, reverses that. Instead of making a model dig through your site, you hand it a clean, structured summary in Markdown that says who you are, what you do, and which pages are worth reading for details. It works roughly as the inverse of robots.txt: where robots.txt tells crawlers what to stay out of, llms.txt tells them what deserves their attention.
What goes in an llms.txt file?
The format is deliberately simple. It's a Markdown document with a handful of conventional parts:
- A top-level heading with your business name. It's the one required element.
- A short blockquote summary of one or two sentences saying what you do, where, and for whom.
- Sections of links, each with a one-line description: your services pages, service-area pages, pricing, FAQs, about page.
- An optional section for secondary pages a model can safely skip when context is short.
For a plumbing company, the whole file might run fifteen lines: the name, a summary ("Emergency and scheduled plumbing for homeowners in the northern suburbs"), and links to the services, service-area, and contact pages with a sentence of context each. Accuracy matters more than length. This is one of the few places on the web where you write directly for the machine reader, so skip the marketing adjectives and state facts: services, locations, hours, what makes you the right call.
Do AI engines read it?
Adoption is uneven, and no major engine has publicly committed to using llms.txt in a way that changes its answers. Some AI crawlers request the file; whether it changes what they say is unproven, and anyone who tells you otherwise is guessing.
It's still worth doing, because the cost-benefit math is lopsided. Publishing one costs you an hour once and a few minutes a year to maintain. If it does nothing, you've lost almost nothing. If assistants consult it more over time (plausible, given the direction of travel), you're ahead of most local competitors, who have never heard of it. Keep it in proportion, though. llms.txt is a courtesy map rather than a strategy, and most of the real gains come from making your content answer-shaped and making sure crawlers can reach your site at all.
How do you publish one on any site?
llms.txt is just a text file, so publishing is mostly a question of getting it to your domain root:
- Write the file in any text editor and save it as llms.txt.
- Upload it to the root of your site, next to robots.txt. Use SFTP, your host's file manager, or your deploy process on a static site.
- WordPress users can upload through the hosting file manager, or use one of several plugins that generate and serve the file.
- Verify by loading yourdomain.com/llms.txt in a browser. If you can read it there, so can a crawler.
Some closed website builders don't let you place arbitrary files at the domain root. If yours doesn't, don't go to great lengths over it, because llms.txt is a nice-to-have.
What llms.txt won't do
It can't unblock a firewall that's turning AI crawlers away or rescue thin content, and it does nothing for your Google Business Profile, which still does a great deal of work in how assistants describe local businesses. Treat it as one small item on the larger generative engine optimization checklist. Publish and verify it, then move on to the work that demonstrably matters. If you'd rather see the whole checklist scored for your site in one pass, an automated audit like Speak Local's will check llms.txt alongside the things that gate visibility: crawler access, rendering, and structured data. Either way, the file is worth the hour it takes.
