Hi Xerter,
App Volume agent will do two functionality , one is act as agent for writable and app stack in VDI machines , so we should install agent on the VDI master machine.
Secondly agent is needed for creating a provisioning machine for app stack.
you can go ahead and install app volume agent on the VDI master image and you need to recompose again to reflect this in VDI VM's.
The fact here is , if you have already created appstacks , VDI master image and the appstack provisioned machine should be in same patch level
Thanks & Regards in Plenteous .
Hari Rajan