mullion-agent-guidelisted

# Mullion agent guide (pointer) If you're reading this, you're likely running as an agent CLI inside a Mullion-hosted session in this repository (or a checkout of it). Mullion gives a hosted session three ways to reach back into the system hosting it — the `mullion` CLI, an MCP server, and a hook socket — each scoped to the session itself, not full operator access. The full guide lives at `docs/agent-guide.md` in this checkout — read it first, especially its "scope model" section, before reaching for any command syntax. It covers: the four environment variables every session gets, what's reachable at session scope vs. full scope, CLI vs. MCP, browser automation, child-session spawning, and notifying the human. If you were spawned by Mullion (rather than just working in a checkout of this repo), a session-specific copy of that same file was very likely already written for you at `$(dirname "$MULLION_HOOK_SOCKET")/$MULLION_SESSION_ID.agent-guide.md` — that copy is identical content, just resolved without needing this repo's working tree. Either source is authoritative; this file is a pointer to them, not a third copy — see `docs/agent-guide.md` itself for the mechanism.