[BUG] Cowork Progress widget does not refresh after tasks are deleted via chat

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?

[BUG] Cowork Progress widget does not refresh after tasks are deleted via chat
Summary
When all tasks are deleted via chat through TaskUpdate (status deleted), the backend correctly clears the task list but the Progress widget in the right sidebar continues to render the old tasks indefinitely until the Cowork window is restarted.
Environment
Claude Desktop, Cowork mode
Model: Claude Opus 4.7 (claude-opus-4-7)
Date observed: 2026-04-20
OS: macOS
Reproduction steps
Have an active Cowork session with a populated task list (in my case, 21 tasks accumulated across prior sessions, mixed status: completed, in_progress, pending).
Ask Claude to clear all tasks and reset.
Claude iterates through each task and calls TaskUpdate with status set to deleted.
Claude then calls TaskList and receives "No tasks found."
Observe the Progress widget in the right sidebar.
Expected behavior
The Progress widget reactively updates to reflect the empty backend state. No tasks should be visible.
Actual behavior
The Progress widget continues to display the original pre deletion task list (tasks 1 through 28, most completed, some pending, some in progress). The list is stale and does not match the backend.

Refreshing or scrolling the widget does not clear it. Only restarting the Cowork window forces the widget to re fetch and render the empty state.
Impact
Low severity on functionality (backend is correct), but moderate on trust. A user looking at the widget reasonably assumes it reflects truth and may believe a clear command failed. In my session, I had to confirm the clear had worked by asking Claude to re query TaskList, which is an extra step that should not be necessary.
Related issues
This appears to be the same category of bug as:

#35717 Scheduled tasks sidebar not updated after removal via chat
#44776 Task responses vanish from chat after switching between tasks

Suggest auditing all Cowork sidebar widgets for the same reactive state sync issue.
Suggested fix direction
The Progress widget should subscribe to task list change events or poll TaskList on a short interval rather than caching on first render. Alternatively, surface a manual refresh control on the widget header so users can force a resync without restarting the window.

What Should Happen?

progress widget should check off tasks and reset when tasks are updated

Error Messages/Logs

Steps to Reproduce

[BUG] Cowork Progress widget does not refresh after tasks are deleted via chat
Summary
When all tasks are deleted via chat through TaskUpdate (status deleted), the backend correctly clears the task list but the Progress widget in the right sidebar continues to render the old tasks indefinitely until the Cowork window is restarted.
Environment
Claude Desktop, Cowork mode
Model: Claude Opus 4.7 (claude-opus-4-7)
Date observed: 2026-04-20
OS: macOS
Reproduction steps
Have an active Cowork session with a populated task list (in my case, 21 tasks accumulated across prior sessions, mixed status: completed, in_progress, pending).
Ask Claude to clear all tasks and reset.
Claude iterates through each task and calls TaskUpdate with status set to deleted.
Claude then calls TaskList and receives "No tasks found."
Observe the Progress widget in the right sidebar.
Expected behavior
The Progress widget reactively updates to reflect the empty backend state. No tasks should be visible.
Actual behavior
The Progress widget continues to display the original pre deletion task list (tasks 1 through 28, most completed, some pending, some in progress). The list is stale and does not match the backend.

Refreshing or scrolling the widget does not clear it. Only restarting the Cowork window forces the widget to re fetch and render the empty state.
Impact
Low severity on functionality (backend is correct), but moderate on trust. A user looking at the widget reasonably assumes it reflects truth and may believe a clear command failed. In my session, I had to confirm the clear had worked by asking Claude to re query TaskList, which is an extra step that should not be necessary.
Related issues
This appears to be the same category of bug as:

#35717 Scheduled tasks sidebar not updated after removal via chat
#44776 Task responses vanish from chat after switching between tasks

Suggest auditing all Cowork sidebar widgets for the same reactive state sync issue.
Suggested fix direction
The Progress widget should subscribe to task list change events or poll TaskList on a short interval rather than caching on first render. Alternatively, surface a manual refresh control on the widget header so users can force a resync without restarting the window.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

4.6

Claude Code Version

Cowork

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_