Agent guide and llms.txt

The agent guide

v0 Hallway ships an agent guide, available three ways:

hallway guide                           # print it
curl http://localhost:4255/agent-guide.md
curl http://localhost:4255/llms.txt     # a summary; /llms-full.txt has everything

Like Local Review’s, it is rendered with live context: the daemon’s version and URL, the data home path, the mode (direct or fronted) and base domain, and the slugs of the apps and bookmark groups that exist right now.

What it covers:

1. What Hallway is, in two sentences.
2. The rule: never start a long-running server directly. Use hallway run <slug> -- <command>, and why, with the framework flags.
3. How to register an existing server: the minimal apps/<slug>.yaml, or hallway app add.
4. How to add bookmarks.
5. How to check status: hallway status --json or GET /api/state, including what was lost at the last reboot.
6. The HTTP API, the MCP server and the optional hook, and that hallway setup and teardown are the user’s to run (they need sudo).
7. The file formats, generated from the same schema the validator uses, so the guide can’t drift from the code.
8. Etiquette: never change a port, never delete outside apps/ and bookmarks/, prefer adhoc for throwaway servers, leave machine-written directories alone.

The snippet for your instruction files

v0 Agents follow what their instruction files tell them. hallway guide --snippet prints this, for your AGENTS.md, CLAUDE.md or equivalent:

Never start a long-running dev or preview server directly (npm run dev, vite, astro dev, next dev, python -m http.server, …). Start it with hallway run <slug> -- <command>, which keeps it running outside this session on a stable port and prints its URL. Run hallway guide for details.

The optional hook

v2 For Claude Code, hallway hook check-command is a PreToolUse hook on its Bash tool. It reads the hook’s payload from stdin and, if the command starts a dev server directly, denies it with a message giving the equivalent hallway run invocation. It is documented, never installed automatically: see The dev-server hook for what it catches and how to add it.

This site’s llms.txt

This documentation site has its own llms.txt and llms-full.txt, and every page is available as Markdown at its URL with .md instead of the trailing slash (this page is /agents/agent-guide.md).