Thanks for the suggestion, and for the screenshot.
You’re right that there isn’t currently a way to rename a workspace itself in the Agents view. The workspace title shown there is generated automatically from the folder or repository name, and there’s no manual override for it yet.
A couple of related things that do work today, in case they help in the meantime:
You can rename individual agents. Double-click an agent’s name in the list, or right-click it and choose Rename.
When you create a workspace from more than one folder (a multi-root workspace), you can give it a custom name at the point of creation.
We don’t have a confirmed work item on this, but we can re-visit it in the future (and others can weigh in here, which helps us to prioritize these types of things)