With the agents being a somewhat autonomous application the status of "Active" is what we use to describe an machine that has the agent installed and running with it's policy. Some additional details is that the console will not automatically refresh the view machines information. You have to click the refresh button to see updated information such as agent scan results etc after the agent has run the scan and checked back in. (If the console is left open) If not the console updates this when you go to view machines.
If you uninstall the agent manually on the agent machine the console will not know the agent is removed and will still list the agent as "active".
alright! thank you!