AI search

llms.txt explained

Published 26 August 2026 · Updated 26 August 2026 · 5 min read

A plain text file describing your site for AI systems. Cheap to publish, unproven in effect, and worth doing only once the basics are right.

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The idea is straightforward: a markdown file at the root of your domain that tells AI systems what your site is, what matters on it, and where to find the important pages, without them having to infer it from navigation and markup.

What it usually contains

A one line description of the organisation and what it does.
Links to the pages that matter most, with a sentence explaining each.
Key facts worth getting right: what you offer, where you operate, how you are regulated.
Anything you would want an assistant to state accurately about you.

Does it work?

Honestly, the evidence is thin. Adoption by the major systems is partial and inconsistent, and there is no reliable public data showing a citation benefit. The case for publishing is that it takes under an hour and may pay off later, not that it is a proven tactic.

Be wary of anyone selling it as a significant deliverable. If an agency lists it prominently in a proposal, weigh that against what SEO should cost and what genuinely counts as new work.

Things that matter more

Structured data describing your organisation and services. See structured data in an AI world.
Clear, direct answers on the pages themselves. See how to become the source AI cites.
Consistent business details everywhere you appear. See the local SEO guide.
A site that can actually be crawled. See technical SEO explained.

If those are in place and somebody has a spare hour, publish one. If they are not, spend the hour on them instead, and consider an SEO audit in Bristol to find out which is which.

Good to know

Frequently asked questions

Is llms.txt an official standard?

No. It is a community proposal. Some tools and systems read it, many ignore it, and nothing obliges anyone to honour it.

Does it replace robots.txt?

No. Robots.txt controls access. llms.txt describes content. They do different jobs and both can exist.

Could publishing one hurt me?

Not meaningfully, provided it contains nothing you would not publish publicly anyway. The risk is opportunity cost rather than harm.

Who should bother?

Sites with a lot of content and a clear structure gain most. A five page brochure site gains almost nothing, because everything is already obvious.

Written by the CompareSEO Bristol editorial team. We are an independent directory and we do not sell SEO services, so nothing here is written to win your business. Read our methodology for how we compile and check what we publish.

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