Hooks / notifications

Terminal bell on permission prompt

Rings the terminal bell when Claude asks for permission, via the terminalSequence output field.

What it does

The simplest hook in the library: a one-line command that rings the terminal bell on permission prompts. No script file, no jq, nothing to install. Hooks run without a controlling terminal, so a plain printf of the BEL character never reaches your terminal - it lands in the debug log. Instead the hook prints a tiny JSON object with the terminalSequence field (bare BEL is on the allowlist), and Claude Code emits it through its own terminal write path. Interactive sessions only: in -p mode or the Agent SDK the field is ignored.

When it runs

Config

Merge this into .claude/settings.json (or ~/.claude/settings.json for user scope) - or use the generator to combine hooks.

{
  "hooks": {
    "Notification": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "printf '{\"terminalSequence\":\"\\u0007\"}'",
            "timeout": 5
          }
        ],
        "matcher": "permission_prompt"
      }
    ]
  }
}

Install

1. Add the config fragment to ~/.claude/settings.json. That is the whole install.

Test it

• Positive: trigger a permission prompt in an interactive session - the terminal bell rings (check your emulator's bell settings if silent).
• Negative: regular output should not ring.
• Note: in non-interactive (-p) runs nothing rings - Claude Code ignores terminalSequence there.

Sources

• Claude Code hooks reference (checked 2026-09-10)

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