In the SDK Reference you can find all the types of events that can exist, and the TaskEvent is one of them.
The Get-VIEvent cmdlet returns all events, so we have to filter them with a Where-clause so we only keep the ones we want.
The -is operator allows you to verify the type of an object.
In PowerCLI the framework has defined all the objects, the are in the VMware.Vim namespace.
The TaskEvent is a general event, it will be created for all tasks that are fired. In the Info.descriptionId property we can see the type of task. So we add that to the Where-clause to only get the specific tasks we want.
Afaik there is not really a document descrbing all of this, it's experience I'm afraid.
Looking at other people's script, writing your own scripts and of course raising questions in this community.
So no tool 