What llms.txt is, and isn't.

What llms.txt is

The idea is simple. Websites are built for people: menus, images, scripts, and pages spread across a site. A language model reading your site has to dig through all of it. An llms.txt file gives it the short version in one place, in plain text.

The proposal describes a markdown file at the root of your site, with a predictable shape:

• A title. Your business or project name, as a top-level heading.
• A one-paragraph summary. Written as a quote block, with the key facts.
• Optional details. Any notes a reader needs to understand the rest.
• Sections of links. Headed lists of your most useful pages, each with a short note on what's there.

The proposal came out of software documentation, where developers wanted AI coding tools to read their docs accurately. It has since spread to all kinds of sites.

What it isn't

• Not an official standard. It's a public proposal. No standards body has adopted it.
• Not a ranking factor anyone has confirmed. No major AI company has publicly said it uses llms.txt to rank or choose sources. Assistants like ChatGPT and Gemini find local businesses mostly through web search, listings, and reviews.
• Not robots.txt. robots.txt tells crawlers what they may access. llms.txt doesn't allow or block anything.
• Not a replacement for your pages. If a fact isn't on your actual website and listings, putting it only in llms.txt won't help much.

Is it worth doing?

Yes, as the last item on the list. It takes ten minutes, costs nothing, and can't hurt as long as it's accurate. Some AI tools can read it when they're pointed at a site, and writing one makes you put your key facts in one clear place, which is useful on its own.

Just don't pay someone extra for it, and don't believe anyone who says it's the reason a business shows up in AI answers.

An example for a local business

Here's what a good one looks like for a fictional HVAC company. Keep it short, factual, and consistent with your website and Google Business Profile.

# Example Heating & Air

> Example Heating & Air is a licensed HVAC contractor in Sandy, Utah,
> serving the south Salt Lake Valley. We repair, maintain, and install
> furnaces, air conditioners, heat pumps, and water heaters for homes.

Key facts:
- Service area: Sandy, Draper, South Jordan, Midvale, Cottonwood Heights
- Hours: Mon-Fri 7am-6pm; emergency no-heat calls answered 24/7
- Pricing: diagnostic visit has a flat fee, credited toward the repair
- Licensed through Utah DOPL; insured
- Book: https://example.com/book/ or call (801) 555-0100

## Services

- [Furnace repair](https://example.com/furnace-repair/): same-day service
- [AC repair](https://example.com/ac-repair/): all major brands
- [Heat pumps](https://example.com/heat-pumps/): installs and estimates
- [Maintenance plans](https://example.com/maintenance/): spring and fall tune-ups

## Service areas

- [Sandy](https://example.com/sandy/)
- [Draper](https://example.com/draper/)

## Optional

- [About us](https://example.com/about/)
- [Reviews](https://example.com/reviews/)

Fictional business for illustration. The 555-01xx phone number is reserved for fiction.

The "Optional" section is part of the proposal: it marks links a model can skip if it's short on space. For a real file, use your real numbers and link to pages that exist. You can see our own at https://almanacoffice.com/llms.txt.

How to add one

1. Write it. Start from the example above. Use the exact business name, phone, and service area that appear on your website and Google Business Profile.
2. Upload it to your site's root. It should load at yoursite.com/llms.txt as plain text. On most hosts that means putting the file in the top folder of the site. Some site builders don't allow custom files at the root; if yours doesn't, skip it. It isn't worth switching platforms over.
3. Check it. Open the URL in a browser and confirm it shows plain text, not your 404 page.
4. Keep it current. When you add a service, a town, or change hours, update it with everything else.

Common mistakes

• Stale facts. Old hours, a dropped service, or a town you no longer cover. An out-of-date summary is worse than none, because it contradicts your real pages.
• Marketing copy. "Utah's most trusted, award-winning comfort experts" tells a model nothing. Facts do: what, where, when, how to book.
• Keyword stuffing. Repeating "best HVAC Sandy Utah" twenty times doesn't help anywhere, and it reads like spam.
• Broken links. Every link should go to a page that exists and says what the note promises.
• Facts that live only in llms.txt. If your prices or service area aren't on your website and Business Profile too, add them there first.

What matters more

If you're working on showing up in AI answers, do these first, roughly in this order:

• Listings. A complete Google Business Profile, plus Bing Places, Apple Business Connect, Yelp, and the directories in your trade, all with matching details. The Business Profile checklist.
• Reviews. Fresh, steady, and replied to, on Google and beyond.
• Clear pages. A page per service and town that answers the question in plain words, with prices or ranges where you can give them.
• Crawler access. Make sure your robots.txt and security settings aren't blocking the search crawlers AI assistants use, like OAI-SearchBot, Claude-SearchBot, PerplexityBot, and Bingbot.
• Structured data. schema.org markup for your business, services, and FAQs.

The full list, with what we found testing AI assistants on Utah searches, is in how to get recommended by ChatGPT and AI search. Almanac Office's AI visibility service handles all of it, llms.txt included, and checks every month whether the major assistants name you. A free audit includes a quick AI-visibility check.