Agent skill · software engineering · sundial-org
timer
Set timers and alarms. When a background timer completes, you receive a System notification - respond with the reminder message (NOT HEARTBEAT_OK) to notify the user.
Why this skill is useful
Adds specific commands for managing timers in a Node.js environment that the AI wouldn't reliably generate on its own.
What it needs
Requires node installed locally. About 2k tokens when loaded. Last updated 2026-03-07. 639 stars on the source repository.
What this skill does
Timer Set timers that run in the background. When they complete, you will receive a system notification and MUST respond with the reminder to notify the user. Quick Start Time Formats Format Description Example -------- ------------- --------- Ns N seconds 30s, 90s Nm N minutes 5m, 15m Nh N hours 1h, 2h N N minutes (default) 5 = 5 minutes MM:SS Minutes and seconds 5:30 HH:MM:SS Hours, minutes, seconds 1:30:00 ⚠️ CRITICAL: Timer Completion Notification When a timer completes, you receive a System: message like: ❌ WRONG - Do NOT respond like this: This response will be filtered and NOT delivered to the user! ✅ CORRECT - Respond like this: Start directly with the notification message. Do NOT include HEARTBEATOK. Why? Responses starting with HEARTBEATOK followed by less than 300 characters are automatically suppressed and never reach the user. Your timer notification will be lost! Examples Cooking Timer When complete, respond: "⏰ Your 12-minute timer is up! Pasta is ready!" Quick Reminder Pomodoro Session Multiple Timers Managing Timers Notes Timers run as background processes with unique sessionIds Completed timers exit with code 0 Cancelled timers (via kill) exit with code 130 Sound notification plays on macOS when timer completes (if afplay available) Progress is logged every second (short timers) or every 10 seconds (long timers)
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills sundial-org/timer