Herdr

Herdr is an open-source agent multiplexer that lives in the terminal: a single ~10MB Rust binary that runs multiple AI coding agents in parallel with panes, tabs, and workspaces — similar to tmux but agent-aware. It tracks semantic agent state in a sidebar (blocked, working, done, idle) so you always know which agent needs input, and sessions persist across detach/reattach, including over SSH from a phone. A CLI and local JSON socket API let agents themselves create workspaces, split panes, spawn helpers, and subscribe to state changes.