Remote trigger cron schedule never fires — manual runs work fine

Summary

Remote triggers created via the RemoteTrigger API (and confirmed in the web UI at claude.ai/code/scheduled) never fire on their cron schedule. Manual runs via action: "run" work perfectly every time — the agent executes, completes its workflow, and produces the expected output. But the same trigger sitting on a cron expression never fires automatically.

Reproduction

1. Create a remote trigger with a cron expression (e.g., 0 13 * * * for daily at 1 PM UTC)
2. Confirm trigger shows enabled: true in both the API response and the web UI
3. Confirm next_run_at is set to the expected time
4. Wait for the scheduled time to pass
5. Result: No run is initiated. No output. No evidence of execution.
6. Manually trigger via action: "run" → works immediately, every time.

What I've tried

• Multiple triggers: Created 3+ separate triggers over 2 days. None fired on schedule.
• Different cron expressions: Tried 0 14 * * *, 52 14 * * *, 3 15 * * *, 0 13 * * *. None fired.
• Recreated from scratch: Deleted old triggers via the web UI and created brand new ones. Fresh triggers also don't fire on cron.
• Verified enabled: true: Confirmed via both action: "get" and the web UI.
• Verified next_run_at: The API returns a valid next_run_at timestamp. That time passes. Nothing happens. The next_run_at then advances to the next occurrence.
• Different timing windows: Tested cron times minutes away, hours away, and next-day. None fired.
• Manual trigger immediately after: Running action: "run" on the same trigger works instantly, confirming the trigger config, environment, and prompt are all valid.

Environment

• Environment: claude-code-default (env_01VmLDyWMQuvDfGWxTeBGBnD, anthropic_cloud)
• Model: claude-sonnet-4-6
• Tools: Bash, Read, Write, Edit, Glob, Grep, WebSearch, WebFetch
• No MCP connections
• Trigger created via CLI RemoteTrigger tool

Expected behavior

Trigger fires automatically at the time specified by the cron expression, same as a manual action: "run".

Actual behavior

Trigger never fires on schedule. Only manual runs work.

Additional context

• The next_run_at field in the API response does advance past the scheduled time, suggesting the scheduler is aware of the trigger but not executing it.
• This has been consistent across 48+ hours of testing with multiple triggers and cron expressions.
• The web UI at claude.ai/code/scheduled shows the trigger as enabled with the correct schedule.