Clock — Session Scheduler

Schedule a recurring task in your session. Reports the current time, then sets up a CronCreate loop.

Usage

code

/clock                          # default: time every 15 min
/clock 15m                      # time every 15 min (explicit)
/clock 4h /background-usage     # run /background-usage every 4 hours
/clock 30m remind me to stretch # custom reminder every 30 min
/clock 1h time                  # time every hour

Arguments:

•interval (optional): Duration like 15m, 30m, 1h, 4h. Default: 15m
•
action (optional): What to do on each tick. Default: time
- •time — report current time
- •/skill-name — invoke a skill (e.g., /background-usage)
- •any other text — use as a reminder message

Supported intervals: 15m, 20m, 30m, 1h, 2h, 4h. Other values are not supported — ask the user to pick a supported interval.

Steps

1. Parse arguments

Extract interval and action from the arguments. If no arguments, use 15m and time.

2. Report current time and execute action immediately

Always report the current time first:

bash

echo "PST: $(TZ='America/Los_Angeles' date '+%I:%M %p %Z (%A, %B %d, %Y)')"

Tell the user conversationally:

It's 3:45 PM PST, Monday Mar 17.

Then execute the action right now (this IS the first tick — no separate one-shot needed):

•If action is time: you just reported it, done.
•If action is /skill-name: invoke the skill now.
•If action is custom text: show the reminder now.

3. Convert interval to cron expression

Interval	Cron expression	Notes
`15m`	`3,18,33,48 * * * *`	At :03, :18, :33, :48 each hour
`20m`	`7,27,47 * * * *`	At :07, :27, :47 each hour
`30m`	`7,37 * * * *`	At :07, :37 each hour
`1h`	`57 * * * *`	At :57 each hour
`2h`	`57 /2 * *`	Every 2 hours at :57
`4h`	`57 /4 * *`	Every 4 hours at :57

4. Build the cron prompt

If action is time:

code

Report the current time to the user. Run: TZ='America/Los_Angeles' date '+%I:%M %p %Z (%A, %B %d, %Y)' — then tell them the time in one line, e.g. "Clock: It's 4:48 PM PST, Monday Mar 17." Keep it to one line.

If action is a /skill-name:

code

Run the <skill-name> skill now. Use a background Agent subagent (run_in_background: true) so it doesn't block the main conversation.

If action is custom text:

code

Reminder: <the text>. Also report the current time (run: TZ='America/Los_Angeles' date '+%I:%M %p %Z').

5. Create the recurring cron job

•cron: (from step 3)
•recurring: true
•prompt: (from step 4)

6. Set up self-renewal

CronCreate jobs auto-expire after 3 days. Create a one-shot renewal that fires ~70 hours from now and re-invokes /clock with the same arguments.

Use date to calculate the renewal time reliably. GNU vs BSD date differ — use whichever works on the host:

bash

# Linux / GNU coreutils
date -u -d '+70 hours' '+%M %H %d %m *'

# macOS / BSD
date -u -v +70H '+%M %H %d %m *'

Use that output directly as the cron expression.

•cron: (output of the date command above)
•recurring: false
•prompt: The clock cron job is about to expire. Re-invoke: /clock <original arguments>. Run the skill now.

7. Confirm

Scheduled: <action> every <interval>. Auto-renews before the 3-day expiry.

Notes

•If the user runs /clock again with the same or different args, just create new cron jobs — a few hours of overlap is fine.
•All cron minutes are offset to avoid :00/:15/:30/:45 congestion marks.
•Session-only: all cron jobs die when Claude exits.
•For /skill-name actions, the skill must be available in the session.