When generating a tool in Nova, there should be a routes/api.php where you can register custom routes for the tool in a way that is familiar to the standard laravel routing definitions. Can you give any examples of what you're trying to do?
Oh not that, but ok, I'm trying to use this https://github.com/runlinenl/nova-profile-tool
However, it adds as a tool instead of under the top right user icon.
I'm looking for a way to add a link to the top right user icon via route name instead of having to hardcode it or stitching it together using nova.path and a string