Someone asked ChatGPT to recommend a plumber in your suburb last week, and an llms.txt file for your website could have helped it find you. It did not mention you. Not because your work is bad, but because the assistant could not work out what you actually do from your website.
The file fixes part of that. It is a plain markdown file sitting at the root of your domain that tells AI assistants, in ordinary English, what your business does, which pages matter, and where the detail lives. Think of it as robots.txt for the AI era, except instead of controlling crawlers it briefs them.
Below: what the file is, what goes inside it, how to write one in an afternoon, and the things it will not do for you no matter how well you write it.
Key Takeaways
- An llms.txt file for your website is a plain markdown file at your root domain that tells AI assistants what you do and which pages matter.
- It is a proposed standard from Answer.AI, not an official search requirement, so treat it as cheap insurance rather than a ranking lever.
- AI assistants read stripped-down HTML, so menus, sliders and pop-ups often bury the one paragraph that actually explains what you sell.
- A good file names your business, your location, your services and your ideal customer inside the first three lines, then links to the detail.
- Most small business sites need one file under 100 lines. Writing it takes an afternoon; updating it takes ten minutes a quarter.
- llms-full.txt is the optional long version that inlines your page content so an assistant can pull everything in one request.
- Adoption across AI tools is uneven, but writing the file forces the clarity your human visitors needed anyway.
What an llms.txt File for Your Website Actually Is
The idea came from Jeremy Howard at Answer.AI in September 2024, and the spec lives at llmstxt.org. The problem it solves is boring and real: an AI assistant trying to answer a question about your business has a limited context window, and your homepage HTML is mostly not content. It is navigation markup, tracking scripts, cookie banners, carousel configuration, and a footer with 40 links in it.
So the file is a curated brief. Markdown, because models read markdown well. Root domain, because that is where tools look. One file, deliberately short.
It is worth being precise about what it is not, because three files get confused constantly.
robots.txt is a permissions file. It says which crawlers may access which paths. It is about access, not meaning.
sitemap.xml is a machine index. It lists every URL on your site with no ranking of importance and no explanation of what any page contains. Useful for search engines, close to useless for an assistant trying to summarise you in two sentences.
llms.txt is an editorial summary. You choose what matters. You explain, in a sentence per link, why someone would open that page. It is the difference between handing someone your entire filing cabinet and handing them a one-page briefing note.
The other thing worth knowing: nobody is obligated to read it. There is no consortium enforcing this and no penalty for skipping it. It is a convention that spread because it is useful, in the same way robots.txt did before anyone standardised it.
Why AI Assistants Get Your Business Wrong Without One
Picture a courier with a parcel, standing in front of three identical doors and a letterbox with no number on it. That is an AI assistant on most small business websites.
Here is what goes wrong in practice.
Your offer is in a slider. Rotating hero banners are still everywhere, and the text inside them frequently never makes it into the raw HTML an assistant reads. The one line that says “commercial refrigeration servicing across Waikato” exists only as a JavaScript-rendered frame that loads two seconds after the crawler has moved on.
Your copy is a mood, not a description. “We help ambitious brands grow” tells a model nothing. It cannot tell if you are a design studio, a recruiter, a franchise consultant or a coffee supplier. Vague positioning that a human forgives because they arrived from a referral is fatal when the reader has no context at all.
Your detail is in PDFs. Service lists, price sheets and capability statements sitting in downloadable files are frequently invisible.
Your site is 400 pages, and none of them is flagged as important. The assistant has no way to know your entire business runs on one service line and the other 380 pages are old blog posts.
The cost is not theoretical. People now ask assistants to shortlist suppliers before they ever open a search results page, and Google surfaces AI-generated answers above the organic listings. If the model cannot describe you accurately, you are not in the shortlist. You are not even in the room.
This is the same failure mode I see inside businesses that bolt AI onto their operations without giving it any context first, which is a big part of why so many AI adoption attempts in small businesses stall out. The tool is fine. It just does not know anything.
What Goes Inside the File
The format is deliberately simple. Four parts, in order.
The header block
One H1 with your business name. Then a blockquote of one to three sentences summarising what you do, where, and for whom. This is the single most important part of the file. If an assistant reads nothing else, it reads this.
Then one or two short paragraphs of plain prose for anything that does not fit the blockquote: service area, hours, who you are not for, licences or certifications, how to get hold of you.
The link sections
H2 headings grouping your key pages, each one a bullet list of markdown links with a short description after a colon. The description matters as much as the link. “Emergency plumbing” is a label. “24/7 callouts for burst pipes, blocked drains and leaks” is information.
A section titled ## Optional has a defined meaning in the spec: those links can be skipped when a shorter context is needed. Put your blog archive and secondary pages there.
Here is a complete example for a small trades business.
# Northshore Plumbing
> Family-run plumbing and gasfitting business serving Auckland's North
> Shore since 2009. Emergency callouts, bathroom renovations, hot water
> systems and commercial maintenance. Certifying plumbers and gasfitters.
Northshore Plumbing works with homeowners, property managers and small
commercial sites across Devonport, Takapuna, Albany and Silverdale.
Standard hours are 7am to 5pm weekdays, with a 24-hour emergency line.
## Services
- [Emergency plumbing](https://example.co.nz/emergency): 24/7 callouts for burst pipes, blocked drains and leaks.
- [Hot water systems](https://example.co.nz/hot-water): Repair and replacement of gas, electric and heat pump systems.
- [Bathroom renovations](https://example.co.nz/bathrooms): Full fit-outs, waterproofing and council sign-off.
## Company
- [About](https://example.co.nz/about): Team, licences and service area.
- [Contact](https://example.co.nz/contact): Phone, email and booking form.
## Optional
- [Advice](https://example.co.nz/advice): Maintenance guides and seasonal checklists.
What to leave out
No keyword stuffing. No marketing adjectives. No repeated variations of your service name hoping something sticks. Models are good at spotting padding, and it dilutes the signal from the parts that matter. Under 100 lines is plenty for most businesses.
How to Write an llms.txt File for Your Website
Five steps, and none of them need a developer.
1. Write the blockquote first, out loud. Say what your business does the way you would say it to someone at a barbecue. Not the website version. The real one. If you cannot say it in two sentences, that is the actual problem, and the file is just where you noticed it.
2. List the ten pages that matter. Not the ones with the most traffic. The ones that answer “what do they sell”, “who is it for”, “how much does it cost”, “how do I contact them” and “why should I believe them”. Ten is usually generous.
3. Write one description per link. One sentence, factual, no adjectives. If the description could apply to a competitor’s page, rewrite it until it could not.
4. Save it as llms.txt and put it at your root. It must resolve at yourdomain.co.nz/llms.txt, served as plain text. On WordPress, you can drop it in the root directory over FTP or use a file manager plugin. On Squarespace, Wix and Shopify, check whether root file uploads are supported on your plan first, because several platforms restrict this and you may need a redirect or a hosting-level upload instead.
5. Open it in a browser. If it downloads instead of displaying, your content type is wrong. If it 404s, it is in the wrong folder. Both are five-minute fixes, and both are the reason most published files do nothing.
Then there is the optional extra: llms-full.txt. Same location, but instead of linking to pages, it inlines the full Markdown content of those pages into one file. Documentation sites use it heavily so an assistant can pull an entire product manual in a single request. For a 20-page service business site, it is usually overkill, but if you have a genuinely deep resource library, it is worth doing.
Set a calendar reminder to review it quarterly. Services change, service areas change, and a stale file is worse than none because it confidently states things that are no longer true.
What llms.txt Will Not Do
Being straight with you, because there is a lot of noise on this topic right now.
It is not a ranking hack. Google has been clear that llms.txt is not a signal it uses for search ranking. Anyone selling you an llms.txt package as an SEO play is selling you something else.
Adoption is uneven. Some AI tools and crawlers read it, some ignore it entirely, and the list changes month to month. Nobody can honestly tell you what percentage of assistant traffic respects it, and you should be suspicious of anyone who quotes a number.
It does not fix bad site copy. If your homepage cannot explain your business, an llms.txt file that can is a contradiction sitting on the same domain. Fix the homepage. The file should be a summary of a clear site, not a workaround for a confusing one.
It does not control what gets said about you. It is a briefing note, not a contract. A model can read it and still get things wrong.
So why bother? Because it costs an afternoon, it cannot hurt you, and the exercise of writing it is worth more than the file. Most founders who sit down to write the blockquote discover they cannot describe their own business in two sentences without hedging. That is not an AI problem. That is the same fog that makes onboarding slow and referrals vague.
Which is the pattern underneath most of this. AI is only as useful as the context you hand it, whether that is an assistant reading your website or AI agents doing actual work inside your business. Skip the context step, and you get generic, confidently wrong output, which is exactly why so many small business AI projects quietly fail.
The Bigger Point
An llms.txt file for your website is a small, cheap, sensible thing to do. Write the blockquote, list ten pages, describe each one honestly, upload it to your root domain, check it loads. Done before dinner.
But notice what it really is: a structured briefing that lets a machine understand your business without a human explaining it. That is the same idea that determines whether AI does anything useful inside your operation. Give the AI a proper brief about who you are, what you sell and how you work, and it becomes genuinely capable. Skip that step and you get a chatbot that guesses.
An AI brain that holds your business context, and an AI workforce that acts on it, both start with the same discipline you just applied to one text file. Most founders have never done it for anything beyond their homepage.
If you want to talk through what that looks like for your business, book a 30-minute Discovery Call. No pitch deck, no pressure. Just a conversation about where you are currently the bottleneck and what could realistically come off your plate first.
Frequently Asked Questions
What is an llms.txt file?
It is a plain markdown file placed at the root of your domain that summarises what your business does and links to your most important pages, each with a short description. It was proposed by Answer.AI in September 2024 so that AI assistants, which have limited context windows, can understand a site without parsing the full HTML of every page.
Is llms.txt the same as robots.txt?
No. robots.txt controls access, telling crawlers which paths they may and may not visit. llms.txt controls understanding, giving an assistant a curated summary of what your business does and which pages matter. They serve different purposes, and you should have both. Neither one replaces the other, and llms.txt grants no permissions at all.
Do AI assistants actually read llms.txt?
Some do, some do not, and the list keeps changing. It is a convention rather than an enforced standard, so support varies by tool and by month. Treat it as low-cost insurance: it takes an afternoon to write, it cannot hurt your site, and the clarity it forces on your own positioning is worth the time regardless of adoption.
Where do I put the llms.txt file on my website?
At the root of your domain, so it loads at yourdomain.co.nz/llms.txt. It must be served as plain text rather than downloaded as a file. WordPress users can upload it directly to the root directory. Some hosted platforms restrict root file uploads on lower plans, so check that before writing it and confirm the URL loads afterwards.
What is the difference between llms.txt and llms-full.txt?
llms.txt is a short index: a summary plus links with descriptions. llms-full.txt inlines the actual content of those pages into one large file, so an assistant can pull everything in a single request. Documentation-heavy sites benefit from the full version. A typical small business site with 20 pages rarely needs it.
Do I need llms.txt if I already have a sitemap?
Yes, because they do different jobs. A sitemap lists every URL with no explanation and no ranking of importance, which is fine for search engines and close to useless for an assistant trying to summarise your business. llms.txt is editorial: you choose the ten pages that matter and explain what each one contains.
Will an llms.txt file improve my Google rankings?
No. Google has said it does not use llms.txt as a search ranking signal, and any provider selling it as an SEO service is misrepresenting what the file does. Its value is in how AI assistants describe your business when someone asks them for a recommendation, which is a separate channel from organic search results.
About Octavius
Titus Mulquiney is the founder of Octavius AI, where he builds AI brains and AI workforces for founder-led businesses stuck running everything out of their own head. Twenty years in marketing, ex-Sony product manager, ex-GM Zeal NZ. Based in Auckland, working with operators across NZ, Australia, and the US. Connect on LinkedIn.