Is llms.txt an official standard?

It's a community proposal. Support varies by AI product, so treat it as low-cost insurance.

Where should the file live?

At the site root: https://yoursite.com/llms.txt.

No. robots.txt controls crawling access. llms.txt only suggests useful content.

Analyzer

Lint an llms.txt file's structure, sections and links, from a live site or pasted text.

Check a live site

…or paste the file

IndexBoost submits your URLs to search engines so both people and AI tools can find them.

Context

01
Title, summary, sections
Start with an H1 site name, add a one-line blockquote summary, then H2 sections of links.
02
Link with a reason
Each entry should be '- [Title](url): what you'll find there'. The description helps models choose what to read.
03
Keep it curated
It's a map of your best content, not a dump of every URL. That's what the sitemap is for.