Judging by the giant knurled piece at the chamber end of the barrel, I would guess it's a tool free design. That is pure speculation though.
I do need a semi auto 22lr, I'm not sure this will sway me away from a Marlin though...
Wanting a semi-auto .22 some years ago I went out to the gun shop fairly fixed on a Savage 64 because is isn't a Ruger 10/22 (price issue,) but they were out of stock and that's how I discovered the Marlin 795. A lucky day.
Today could be the last day of the rest of your life.