What changed in llms.txt v2

v2 of the llms.txt proposal was published on August 10, 2026. The file format itself barely changed. What changed is everything around it: how an agent finds the file, what a file in a subpath means, and how the file is consumed.

v1 came out on September 3, 2024. Both were written by Jeremy Howard (Answer.AI). It remains a proposal by a single author, not an IETF or W3C standard.

A short account of the event: The second edition of llms.txt is out.

The most common request from the community: given a page, how does an agent find its Markdown version, or the llms.txt that covers it, without guessing the URL.

v2 answers with standard link relations:

<link rel="alternate" type="text/markdown" href="/docs/page.html.md">
<link rel="describedby" href="/docs/llms.txt">

The same can be sent as a response header. That form works for any resource, not only HTML, and can be configured on the server without touching pages:

Link: </docs/page.html.md>; rel="alternate"; type="text/markdown", </docs/llms.txt>; rel="describedby"

More on the relations and headers: Discovery of the file and Markdown versions.

v1 allowed llms.txt outside the root without saying what that meant. v2 defines it:

• a file covers the URLs under its path;
• where more than one file applies, the most specific one is used.

/llms.txt        -> the whole site
/docs/llms.txt   -> everything in /docs/

This lets authors who control only part of a domain take part.

v1 specified a single form: .md appended to the full page URL. Some publishing tools replace the extension instead. v2 allows both:

page.html  ->  page.html.md
page.html  ->  page.md
/docs/     ->  /docs/index.html.md  or  /docs/index.md

v1 described the llms_txt2ctx tool, which expanded a file into a ready context for a model. v2 states the expectation directly: an agent views or searches llms.txt, then follows the relevant links. The links should therefore point to LLM-friendly content.

Along with the tool, the proposal dropped:

• the llms-ctx.txt and llms-ctx-full.txt files;
• the special meaning of the Optional section, which told the tool what to omit.

Optional remains as a convention for secondary links.

v2 explains why it does not use a /.well-known/ address (RFC 8615). Such URIs exist only at the origin root. Many authors control only a path on a shared host and cannot add a file to the root. Like index.html, an llms.txt describes the path where it sits.

• Only the H1 is required.
• The order of parts: H1, blockquote, details without headings, H2 sections with link lists.
• The list item format: a link and optional notes after a colon.
• The file forbids nothing and does not control access.

• llms-full.txt and llms-small.txt. These files emerged as a practice of documentation platforms and are not in the proposal text.
• Requirements for Content-Type.
• A section on security and untrusted content.
• A rule for the language of the root file on a multilingual site.

The last three are open questions in the proposal repository.

1. If the site already has an llms.txt, there is no need to redo it: the format is the same.
2. Check the links in the file: where possible they should point to Markdown versions of pages.
3. If Markdown versions exist, add rel="alternate" type="text/markdown" to the pages.
4. Add rel="describedby" pointing to the covering llms.txt.
5. Do not rely on any special handling of the Optional section.