What is llms.txt?
llms.txt is a small Markdown file you place at the root of your domain (/llms.txt). It gives large language models a fast, plain-English summary of your site: what you do, what your key pages are, and which links matter most. Think of it as a curated table of contents written for AI.
It won't magically get you cited — but it removes friction between your site and every AI retriever. PNX is a free agentic SEO tool built for creators, founders and SEO teams who need real answers — fast — without paying $99/month for legacy platforms. This guide breaks down everything about llms.txt file in plain English, with a comparison table, internal links to our free tools, and a one-click way to try it yourself.
Why it exists
When an LLM crawls a website it usually gets a soup of navigation, tracking scripts, cookie banners, and marketing copy. llms.txt cuts through that noise with a curated list of "if you only read a few pages, read these."
What to put in it
A clean llms.txt has three sections:
# Your Company Name
> One-line description of what you do and who it's for.
## Core pages
- [Home](https://example.com/): what the product is
- [Pricing](https://example.com/pricing): plans and cost
- [Docs](https://example.com/docs): technical documentation
## Guides
- [Getting Started](https://example.com/blog/getting-started): 5-minute setup
- [Advanced Use](https://example.com/blog/advanced): power-user patterns
## About
- [About us](https://example.com/about): team, mission, contact
That's it. No SEO tricks, no keyword stuffing — just accurate, useful links.
Rules that make it actually work
- Only link to indexable, public pages. No login walls, no paywalled content.
- Descriptions are honest. LLMs discount hype.
- Keep it short. Under 100 links. Curated beats comprehensive.
- Update quarterly. Stale entries erode trust.
- Match your sitemap. If it's in llms.txt it should also be in sitemap.xml.
Does it actually get read?
Support is still emerging. Perplexity, some model retrievers, and several AI dev tools already read it. Google and OpenAI haven't officially confirmed usage. Publish it anyway — it's a 10-minute job, it doesn't hurt SEO, and being ready when adoption hits is worth more than doing it after.
Combine with the rest of the stack
llms.txt is one signal. The heavy lifting for GEO is still on-page — see the ChatGPT & Perplexity playbook and Google AI Overviews guide. Confirm your setup with the free SEO audit tool.
Bonus: what NOT to do
- Don't try to hide different content in llms.txt vs your visible site. LLMs check.
- Don't list every blog post — pick your top 20.
- Don't use it as a keyword dump.
Keep reading
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