[BUG] Cowork scheduled task fires on time but doesn't execute until the sidebar item is manually opened (related to #36131, with timing evidence)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Scheduled task (trigger trig_01UG2VMDu4wKxssspVFXR8Ah, cron 0 14 *, daily 7 AM local) fires on schedule but the session doesn't actually execute its tool calls or deliver output until I manually open the pinned scheduled-task item in the sidebar.

Evidence from the routine's own run metadata (Aug 27, 2026):

fired_at: 2026-08-27T14:08:41Z (on schedule)
finished_at: 2026-08-27T21:06:27Z — 6h 58m later
The output (a Slack message) posted at the finish time, not the fire time
I had not opened or interacted with the scheduled task at any point before that day — first interaction was shortly before it completed

This has recurred across multiple days (Aug 20, 22, 25, 27), with completion consistently landing near whenever I next opened the app rather than near the scheduled time. This matches #36131 exactly but with concrete timestamp evidence that report lacked.

What Should Happen?

Expected: task executes fully at the scheduled time regardless of whether the Cowork view is open.
Actual: task "fires" (recorded) on time but stalls until manually opened.

Error Messages/Logs

Steps to Reproduce

steps unclear, this simply happens every day when this scheduled task is supposed to run and push the contents to Slack.

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude 1.37937.3 (28dcf5) 2026-08-26T19:52:45.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_