Your Claude Code sessions outlive the work. Who closes them?

A usage report said most of my sessions had been open for more than eight hours. The fix was a small hourly job, and its first version had a timezone bug that would have closed nothing.

How to do it

1. Read what /usage is telling you before guessing. Mine showed 94% of sessions asking for /clear and 65% open for 8 hours or more, with 10 sessions alive and 9 editor tabs between 15 and 17 hours old.
2. Check the suspect before blaming it. I assumed Remote Control was keeping the tabs alive, but only 2 of the 5 old idle tabs had a bridge at all. The real cause was simpler: an editor tab keeps its process alive until the tab closes, and Claude Code never closes an idle session by itself.
3. Make the reaper narrow on purpose. Mine closes only editor sessions that are idle past a threshold and have no shell or Claude child process. It never touches launchd services, CLI, SDK or memory sessions, and /resume brings any closed session back, so the worst case is a reopen.
4. Give it a --dry-run flag that prints every session with its keep or close reason, plus an --hours flag for the threshold. Run the dry run until each reason reads right, and only then let it close anything.
5. Compare timestamps in one timezone. The session file records the process start in UTC, while ps -o lstart prints local time. Run ps with TZ=UTC. My first version missed this and would never have closed a single session.
6. Schedule it with launchd, once an hour with a 4 hour threshold. Log only the sessions it closed, and send errors to a separate file so the log stays readable.

Write a Python script that lists my Claude Code sessions from ~/.claude/sessions/*.json and closes only editor sessions that have been idle longer than --hours (default 4) and have no shell or claude child process. Add a --dry-run flag that prints every session with a keep or close reason. The session files record procStart in UTC, so compare against ps run with TZ=UTC. Never touch launchd services, CLI or SDK sessions. Log closed sessions to one file and errors to another. Then write a launchd plist that runs the script every hour.