llms.txt: The Robots.txt of the AI Era

There's a file you can put at the root of your website — yoursite.com/llms.txt — that hands AI crawlers a clean, plain-text summary of your business's canonical facts: who you are, what you do, where you serve, the pages that matter. Think of it as the AI-era cousin of robots.txt: robots.txt tells crawlers where they can go, and llms.txt tells the language-model crawlers what's true and important once they get there.

It takes about five minutes to ship. I put one on every site I run. And I want to be honest with you about both halves of that sentence — the "five minutes" and the "why I bother despite the caveat."

What it actually does

An AI assistant answering "who does water treatment near me" is assembling a picture of your business from whatever it can find scattered across the web. The more of that picture is ambiguous or contradictory, the less confidently it can recommend you. An llms.txt file is you writing the summary yourself, in the crawler's preferred format, instead of hoping it pieces the right story together from fragments. Your name, your services, your service area, the canonical version of your facts, and pointers to the pages you most want read — all in one place, plainly stated.

It pairs naturally with the other machine-legibility work: structured data / schema makes your facts legible in a formal vocabulary, and llms.txt makes them legible in plain prose. Same goal — reduce the guesswork — two formats.

The honest caveat

Here's where I part ways with the "AI SEO" hype crowd: llms.txt adoption is early. It's a young convention, not every AI system consumes it, and nobody can promise you it's the deciding factor in whether an assistant recommends you. If someone's selling llms.txt as a magic switch that guarantees AI visibility, that overclaim is the tell that they don't understand it. I don't ship it because it's guaranteed. I ship it because it's cheap, honest, and directionally right — a five-minute, low-risk bet on a surface that's clearly growing.

That "low cost, right direction, no overclaim" posture is the whole philosophy. Overpromising on AI search is the competitor move I most want to avoid. I'd rather tell you it's a modest, sensible hedge than sell it as a miracle.

Go check yours right now

This one's testable in ten seconds. Open a browser and type your own domain followed by /llms.txt. If you get a real file with your canonical facts, someone's paying attention. If you get a 404 or an empty page — which is the common result — you've found a five-minute gap on a surface where more of your customers are asking AI every year.

Shipping it is part of the standard AEO baseline I run for local service businesses, alongside the rest of the machine-legibility work, because none of these pieces is the whole answer on its own — they compound. Go run the /llms.txt check on your site. If it comes back empty, that's the easiest fix on this whole blog. Inquire about a project →