Scheduled routine in a private project never ran

What happened

A scheduled routine in a private project never ran at its scheduled time. Instead, its next run kept getting pushed back without any run being recorded.

• Routine created 2026-10-04 09:43 UTC from a thread in a private project, cron 0 17 * * 0, bound to that thread's session (trigger trig_017xZJ6CMLjB1qQfuBFqArNk).
• After creation, next_run_at showed 17:07 UTC. At 17:07 nothing happened: no last_run, no error, and the thread's session transcript has no events at all between 10:08 and 21:47 UTC (no queued notification, no sandbox allocation).
• Later next_run_at showed 22:29 UTC, still with no run recorded.
• A manual "run now" from the UI at 22:16 UTC was delivered to the same thread session correctly (the session was woken and a sandbox was provisioned). So delivering into the thread works; the scheduler itself seems to have skipped the run.

Possible cause: the thread may have been marked as "resolved" at that time, and routines in private projects can only be bound to a thread. I could not confirm this.

Why it matters

In private projects, routines cannot start a fresh session per run (create_new_session_on_fire is rejected with "not supported for routines created from a private project"), so they have to be bound to a thread. If a thread-bound routine can silently skip its schedule, it is much less reliable than the scheduled tasks in the old Projects, which started a fresh session each run and worked dependably.

Expected

The routine fires at its scheduled time regardless of the thread's state, or at least records a failed run with a reason instead of silently moving the next run.

Environment

• Filed from: Report a problem in Claude Code
• Project ID: chan_018N334b6fzMdZjvyx4MwirN
• Thread ID: cmsg_018N334b6fzMdZjvyx4MwirNV2URMErRkmSRzUhu56amB4