Problem

When running multiple Claude Code sessions simultaneously (e.g., across different projects or tasks), there's no way to know which session is blocked waiting for user input — permission approvals, questions, etc. You have to manually check each tab/window.

Proposed Solution

A built-in notification mechanism when Claude Code is waiting for user input. This could be:

1. macOS/Linux system notification — native OS notification when a session needs attention
2. Audio alert — a sound or say command (especially useful for headless setups like Mac mini accessed via SSH)
3. Hook support — a dedicated onWaitingForInput hook event so users can customize the behavior (e.g., trigger say, osascript, Slack webhook, etc.)

Current Workaround

You can partially achieve this with a preToolUse hook:

{
  "hooks": {
    "preToolUse": [
      {
        "matcher": "*",
        "hooks": [
          {
            "type": "command",
            "command": "say 'Claude needs your attention'"
          }
        ]
      }
    ]
  }
}

But this fires on every tool use, not specifically when approval is needed. A dedicated event for "waiting on user" would be much more precise.

Use Cases

• Running 3-4 Claude Code sessions across different projects
• Headless Mac mini setup accessed via phone/SSH — need ambient audio feedback
• Long-running autonomous tasks where Claude occasionally needs a permission grant
• Pair programming flow where you're focused elsewhere and need to know when Claude has a question

Why This Matters

Claude Code is moving toward more autonomous, multi-session workflows. The bottleneck increasingly isn't Claude's speed — it's the human noticing that Claude is waiting. A simple notification closes that gap.