You require permissions to install and modify a service. If you want to discover a running process, the user account you use to run the agent must also have privileges to access the processes and programs. For Windows operating system installations, you require permissions to install and modify a service. For Linux installations, you require permission to install the agent as a service, if you install the agent using a RPM installer.
The minimum credentials that are required for the agent to register with the vRealize Operations Manager server are those for a user granted the Agent Manager role, without any assignment to objects within the system.