[Feature]: Add a shortcut to jump to the latest unread completed thread

[kyrregjerstad]

Problem statement

When several agent turns run in parallel, completed work can sit unread in another project or environment. T3 shows completion state in the sidebar, but there is no single keyboard action to open the newest unread result. Users must scan projects and thread rows manually.

cmux solves this with Jump to Latest Unread, bound to Cmd+Shift+U. It selects the newest unread notification across windows and workspaces, navigates to the exact target, and marks it read only after navigation succeeds. Repeated presses walk through unread work from newest to oldest.

Solution

Add a configurable Jump to Latest Unread command to the command palette and keybinding registry. Bind it to Cmd+Shift+U by default on macOS.

For the first version, an unread item is a thread whose latest completed turn is newer than its effective viewed timestamp. The command searches all available, non-archived threads across connected environments and projects, selects the candidate with the newest completion timestamp, and navigates to it.

After navigation succeeds and the thread becomes visible, normal thread-view behavior marks the completion read. Pressing the shortcut again therefore opens the next-newest unread completion. If no unread completion exists, the command does nothing.

User stories

1. As a user running several agents, I want one shortcut to open the newest unread completed turn, so that I do not need to scan the sidebar.
2. As a user working across projects and environments, I want the shortcut to search all available threads, so that the current project filter does not hide completed work.
3. As a keyboard user, I want the command in the command palette and keybinding settings, so that I can discover and remap it.
4. As a user reviewing several completed turns, I want repeated presses to move from newest to oldest, so that I can process them as an inbox.
5. As a user on an unreliable or remote connection, I want a thread marked read only after navigation succeeds, so that failed navigation does not lose the unread signal.
6. As a user with no unread completions, I want the shortcut to be a quiet no-op.

Further notes

cmux is the reference behavior:

• Keyboard shortcut documentation
• Notification behavior
• Newest-first selection in cmux

Related T3 work:

• feat(web): add unread notification badge to sidebar toggle button #6652 adds an unread-completion count to the sidebar toggle.
• feat: sync thread unread state across clients #6662 proposes server-owned thread view state across clients.
• Discussion [Feature]: Add an unread indicator for completed sessions #6876 requests unread indicators for completed sessions.

The core idea is an inbox navigation command, not a dependency on desktop notifications.