change(llms-txt): cover the v2 revision — link-relation discovery, path scoping

[jdevalk]

What changed

/llms.txt described v1 of the proposal. llmstxt.org has since published v2, revised after two years of deployment, and the page missed all of it.

• Discovery by link relation. v2's one hard addition: advertise the file with rel="describedby" — a <link> in the head, an HTTP Link header, or both. v1 expected agents to guess /llms.txt at the root.
• Path-scoped coverage. A file covers the pages beneath its path, most specific wins, so /docs/llms.txt can describe the docs and nothing else. A large site can participate one section at a time.
• Both markdown URL shapes accepted — page.md and page.html.md.
• ## Optional lost its mechanical semantics, along with the llms_txt2ctx tooling it existed for. It is now a convention for secondary links and nothing more.
• Adoption paragraph corrected. The page said "no major model vendor has committed to consuming it" and left it there. Publishing is now mainstream — OpenAI, Anthropic and Google each publish one for their own developer docs; Mintlify and GitBook generate them; Chrome's Lighthouse audits for the file under its agentic-browsing checks. Whether any model reads it is still undisclosed, and the page still says so. The now-redundant "assume nobody uses it today" mistake bullet is deleted.

Also: link-headers added to relatedSlugs; a worked-example callout added — the site already emits Link: </llms.txt>; rel="describedby"; type="text/markdown" on every response, so v2 costs us nothing to comply with.

Why now

llms.txt v2 is live at llmstxt.org and changes the page's operative advice, not just its framing. A reader following our v1 instructions ships a file no agent is told about.

Sources

• llmstxt.org (v2) — primary
• llmstxt.org — changes from v1 to v2 — the itemised diff
• RFC 8288 — Web Linking — the describedby relation

Status

Unchanged at recommended. Adoption broadened and tooling now audits for it, but nothing about the web platform breaks without it, and no vendor has committed to consuming it — required would overstate the case.

Included

• src/content/spec/agent-readiness/llms-txt.md
• src/content/changelog/2026-08-11-llms-txt-v2.md (type: changed)
• public/og/spec/agent-readiness/llms-txt.png — regenerated, the summary changed

npm run build passes; page count unchanged at 168, so no SKILL.md digest change.

🤖 Generated with Claude Code

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