Desktop app tasks fail to delete ("could not be deleted, try again") and don't appear in the claude.ai/code web task list

Description

Tasks created in the Claude Code Desktop app cannot be deleted. Clicking "Delete task" and confirming in the "Delete task?" dialog shows a toast: "This task could not be deleted. Try again." Retrying repeatedly gives the same result every time.

Additional finding

These same Desktop-app tasks do not appear at all in the task list on the web app (claude.ai/code). Chats/tasks created directly on claude.ai/code delete normally there. This suggests the Desktop app's task list and the web-facing backend may be out of sync, and the delete request may be targeting a task ID the backend does not recognize.

Steps to reproduce

1. Open the Claude Code Desktop app on Windows.
2. Open an existing/finished task (reproduced with several job-application-related tasks).
3. Click delete, then confirm "Delete" in the "Delete task? Cancel / Delete" dialog.
4. Observe the toast: "This task could not be deleted. Try again." The task is not removed.
5. Repeating the action produces the same failure every time, indefinitely.
6. Separately, open claude.ai/code in a browser and check the task list: the affected Desktop-app tasks are not present there at all, even though other web-created chats list and delete normally.

Expected behavior

The task should delete successfully, or the app should surface a more specific/actionable error.

Environment

• Claude Code Desktop app, Windows 11
• Reported by an end user, relayed via their AI assistant