Single tool with adequate schema and basic description, but significant gaps in parameter documentation, error handling guidance, and output schema definition. The tool description (56 chars) is minimal and lacks context on when/why to use it. Parameters lack descriptions for optional fields (subtitle, sound). No output schema documented. Error handling returns generic failure messages without recovery guidance. Tool performs a destructive action (sends notification) but lacks confirmation pattern or idempotency guidance.

• Expand tool description to 150-250 chars: 'Send a desktop notification to the user via terminal-notifier (macOS only). Use this to alert the user to important events, reminders, or task completions. Requires terminal-notifier to be installed.'
• Add descriptions to optional parameters: subtitle → 'Optional subtitle displayed below the title', sound → 'Optional system sound name or path (e.g. /System/Library/Sounds/Basso.aiff). Defaults to Basso.aiff if omitted.'
• Document output schema: return {type: 'object', properties: {success: {type: 'boolean'}, notification_id: {type: 'string'}, timestamp: {type: 'string', format: 'date-time'}}}
• Enhance error messages with recovery guidance: 'Failed to send notification: terminal-notifier not found. Ensure terminal-notifier is installed (brew install terminal-notifier on macOS).'
• Add a 'dry_run' boolean parameter (default false) to preview the notification command without executing it, enabling agent confirmation workflows.