Cron Expression Format

Scheduled functions use the “cron expression” format used by tools like crontab and are executed according to the UTC timezone. For example, the cron expression 0 0 * * * will run a scheduled function every day at midnight UTC. We also support the extensions in the RFC, except for the @reboot and @annually specifications. With extensions, the expression 0 0 * * * can be written as @daily.