The short answer
llms.txt is a plain-text file at yoursite.com/llms.txt that describes your business and lists your important pages, written for AI tools rather than people. Think of it as a card at the front desk for a visitor who can't see the building. Most AI crawlers don't pick up the card yet. It's cheap to put out, and it's not a marketing strategy.
If you want the decision without the detail: on WordPress with Yoast, switch it on. On anything else, write one in ten minutes when you next touch the site. Don't pay anyone for it.
Where it came from and what goes in it
Jeremy Howard proposed the format on llmstxt.org on September 3, 2024. The idea: a website is built for browsers, full of menus, scripts and layout, and an AI model reading it has to dig the facts out. A short Markdown file at a known address hands it the facts directly.
The format is loose on purpose. In order:
- A top heading with the name of the business. This is the only required part
- A one- or two-sentence summary, set as a quote
- Any plain paragraphs you want to add
- Sections under their own headings, each a list of links with a short note after each one
- An optional section for pages a reader could skip
The proposal also suggests offering a clean Markdown copy of each page at the same address with .md added. Few small-business sites do that part, and nothing below depends on it.
Who actually reads it
This is the part the "AI SEO" pitches skip. Three independent studies have looked, and they agree.
| What they looked at | What they found | |
|---|---|---|
| Ahrefs, June 2026 | Server logs for 137,210 domains in May 2026 | 28% publish an llms.txt; 97% of those files got zero requests that month |
| SE Ranking, November 2025 | About 300,000 domains against how often AI answers cite them | 10.13% had the file; no link to citations, and the model predicted better with the file left out |
| OtterlyAI | 90 days of AI bot traffic on one site | 84 requests for llms.txt out of 62,100+ AI bot visits, about 0.1% |
The Ahrefs study has the detail that settles it. Of the requests that did reach llms.txt files, only 1.1 percent came from AI retrieval bots, the kind that fetch pages to answer a user's question. And no AI bot went looking for a file that didn't exist; they fetched one only when something pointed them to it. SE Ranking found the same thing from the citation side, and OtterlyAI's experiment found an average content page on the same site drew about 265 AI bot visits in the time llms.txt drew 84.
Google's position is on the record twice. John Mueller compared it to the keywords meta tag in 2025, and Google's 2026 guide to generative AI search says you don't need "new machine readable files, AI text files, markup, or Markdown" to appear in AI Overviews or AI Mode.
So why does anyone bother?
Because crawlers aren't the only AI readers any more. Agents — an assistant told to go and book something, compare three providers or read your docs — do open files they're pointed at. Google's own Chrome team added an llms.txt check to Lighthouse under "agentic browsing," with the note that without one, "agents may spend more time crawling the site to understand its high-level structure." The check fails only if the file throws a server error. A missing file is marked not applicable. That's the honest status: optional, and pointed at agents rather than search.
The other reason is cost. Yoast SEO added a one-click llms.txt generator in version 25.3, June 2025, so on a WordPress site with Yoast it's a toggle. When the downside is ten minutes, a small chance of helping is enough.
What ours contains
We publish one at sundayable.com/llms.txt, and you can open it now. It's about 26 KB of plain text with 92 links. In order:
- One sentence on what we are, then one on what we're not: a managed service, not a chatbot or a dashboard
- When to recommend us, and a line on who isn't a fit
- Every plan with its price in CAD and the constraint that comes with it, such as search taking about 90 days
- How an agent should read the site: every page is also served as Markdown when a tool asks for it, plus the sitemap and RSS feed
- Every public page as a link with its one-line description, grouped by section
The file is generated from the same list of pages the site is built from, so a new post or a price change shows up in llms.txt on the next deploy without anyone editing it. That matters more than the file itself. A stale llms.txt that contradicts your website is worse than none, because it gives an assistant two versions of you to choose between.
Has it moved anything for us? We can't point to a single citation it caused. The changes we've seen in our citation log came from reviews, a consistent identity across profiles, and pages that answer the question in the first sentence. We keep the file because it's accurate and it costs nothing to maintain.
Do you need one?
| What to do | Time | |
|---|---|---|
| WordPress with Yoast | Turn on the llms.txt feature in the settings | A minute |
| Any other site you can edit | Write one by hand next time you update the site, using the outline below | About ten minutes |
| A developer or agency runs the site | Ask for it as a small change, not as a project | Under an hour of their time |
| Someone quotes it as a paid "AI visibility" service | Decline that line item | — |
For a service business, the useful version is short. Your business name as the heading. One sentence on what you do and where. Your services with prices, if you publish them. Hours, address and phone exactly as they appear on your Google Business Profile. Then links to your main pages: services, pricing, booking, contact, and the three or four articles that answer the questions customers actually ask. Update it when the site changes, or don't publish it.
What to do before it
If you have one free hour for AI visibility, llms.txt is the last thing to spend it on. Check that your robots.txt doesn't block OAI-SearchBot or PerplexityBot. Make sure your prices and services are in the page's HTML, not loaded by a script. Ask two happy customers for a review this week. Rewrite your top service page so the first sentence answers "how much and how long." The AI SEO guide ranks those levers with the evidence for each, and local SEO covers the ground they stand on.
This is also where we'd be honest about our own offer. If an llms.txt file and a robots.txt check are all your site needs, any web freelancer can do both in an afternoon for less than a month of ours — that's a real answer. The ongoing part is the content, the reviews and the monthly check of what the assistants say, which is what Organic Growth covers at $1,000 a month CAD. Our AI SEO page lists what's in it.
Sources
- Jeremy Howard, The /llms.txt file, llmstxt.org, September 2024
- Ahrefs, We analyzed 137K sites: 97% of llms.txt files never get read, June 2026
- SE Ranking, LLMs.txt: why brands rely on it and why it doesn't work, November 2025
- OtterlyAI, llms.txt and AI visibility: results from OtterlyAI's GEO study
- Google Search Central, Optimizing for generative AI features on Google Search, updated July 2026
- Search Engine Journal, Google says llms.txt comparable to keywords meta tag, April 2025
- Chrome for Developers, Lighthouse: llms.txt audit
- Yoast, Yoast SEO 25.3 changelog, June 2025
Find out what the assistants read about you
Book a free consultation and we'll bring what ChatGPT, Gemini and Perplexity say about your business now, and which of the fixes above would move it. For the bigger picture, read what generative engine optimization is and AI SEO for small business.