Can I keep the SSH key in memory?

[louwers]

I don't want to reauthenticate all the time. Can the agent keep it in memory?

[martinpaljak]

From the popup notification, choose "keep unlocked" with the amount of time you want it to be usable without re-authentication

[chriszarate]

Tip: Make sure you have notifications for Secretive turned on in System Settings > Notifications > Application Notifications > Secretive. Authenticate, then find the resulting notification in the Notification Center. (I was confusing "popup notification" with the Touch ID authentication modal, which has no such "keep unlocked" option.)

[martinpaljak]

I wish it had, because the notification often disappears prematurely or just lacks context, and I get prompted again.