This teaches Claude to use the openclaw cron CLI instead of trying to track time manually, which doesn't work because the model has no internal clock. The key insight is the isolated session mode: when you want Claude to actually do something at a scheduled time (run a check, send a summary, execute a task), it spins up a separate agent session that can use tools and deliver results to chat. Main session is just for simple reminder notifications. It handles the usual cron patterns (every N minutes, daily at 9am) plus duration shortcuts like "+30m" for one-off delayed tasks. The documentation is thorough about when to use which session type and includes a logging format for tracking what jobs got created.
npx skills add https://github.com/tclawde/openclaw-skills-user --skill cron-helper