Notifications
The notification bell in the sidebar collects events that concern you: agent completions, mentions, approvals, and status changes. It is a record of things that already happened, separate from pending actions, which are things waiting for your input.

Open it
Press the bell icon in the sidebar. A badge on the bell shows the count of unread notifications; counts above 99 show as 99+. The panel opens as a popover. On mobile, the panel expands to fill the screen.
Notification types
Reading and navigating
Clicking a notification marks it read and navigates to the related artifact. If the notification is not linked to a specific artifact, it takes you to the project's artifact list.
Press Mark all read at the top of the panel to clear the badge without opening each item.
Notifications vs pending actions
The bell and pending actions serve different purposes. Notifications are events: things that have happened that you might want to know about. Pending actions are tasks: items that cannot proceed until you act on them. You can have unread notifications and no pending actions, or the reverse.
To see what is waiting for your input, ask the assistant "What is waiting on me?" or press the What needs me quick prompt. See Pending actions.