llms.txt

AgentStack publishes a machine-readable documentation index at /docs/llms.txt. The route is static plain text, with the type text/plain; charset=utf-8 and a shared-cache lifetime of one hour. The same Fumadocs source tree that powers the documentation site generates the index. It is not a manually maintained list of pages.

Each current documentation page contributes its URL, title, and description under the https://www.agentstack.build origin. The index sorts entries in lexicographic order. This order makes results predictable for a diff or a crawler. Adding a properly registered MDX page updates the index automatically. Deleting or moving a page removes or changes its entry when the docs build regenerates the index.

Use this index as a discovery aid for language-model or search integrations. Do not use it as a replacement for the rendered docs or the generated API reference. Content still needs accurate titles, descriptions, and navigation metadata. The documentation verifier checks parity with the docs tree, so stale hand-curated entries cannot quietly accumulate.

Do not confuse the two paths

/llms.txt at the site root is a different document. It serves the agent onboarding guide, the same plain text as /agent.md. The paths /AGENTS.md and /agents.md serve that guide too. An AI agent that was never given the address guesses one of these three filenames, so all three answer with one body.

Use the full path /docs/llms.txt when you want the documentation index. Use the root /llms.txt when you want the onboarding guide. Both are plain text with a shared-cache lifetime of one hour, so the type and the cache headers do not tell them apart. See REST API: agent sign-up for the flow the guide describes.