Walk away from a long coding task, then discover it spent the last half-hour waiting for you. u/Fincut solved the checking problem with an old Kuando Busylight, connected to Claude Code through hooks:

• Blinking red: working.
• Solid red: needs input.
• Green: idle.

The spare laptop is helping build 3D models, so a physical signal is useful from across the room. Other developers have shared their own notification setups, including a Stream Deck showing several sessions at once. A modest workflow improvement: make the agent's need for a human visible.