agent-inbox

Write a markdown file with YAML frontmatter (from, to, reply_to, timestamp) into the recipient's tmp/ directory, then move it to their new/ directory. The recipient reads it with cat and archives it with mv — no server or daemon needed.

They share a filesystem inbox rooted beside the repo's common git directory, so all worktrees and tools see the same .agents/inbox tree. Discovery is human-brokered: you tell each agent the other's inbox path, and every message carries a reply_to path for responses.

No. The protocol uses only mkdir, cat, and mv on the local filesystem. Messages are markdown files written atomically via tmp/ then renamed into new/, making it work entirely offline.

Two optional hooks handle notification: a Stop hook (check-inbox-hook.sh) prints a one-line unread count after each turn, and a SessionStart hook (inbox-startup.sh) summarizes unread messages with sender and subject when a session begins. Both are silent when the inbox is empty.

Delivery is pull-based — recipients only see messages when they check their inbox or a hook fires, so there is no real-time push. Discovery is manual, and the wake-parent script depends on cmux and uses --dangerously-skip-permissions for headless sessions.