The Reds signed the likes of Mamadou Sakho, Tiago Ilori and Victor Moses, Kolo Toure, Simon Mignolet, Iago Aspas, Luis Alberto and Aly Cissokho.
Agger is also delighted that the club managed to keep hold of Luis Suarez.
“It has been a positive transfer window for us.” Agger told Danish daily BT.
“We have brought in players with quality and that is what you want. I have not seen all in action yet, but what I have seen thus far is good.
“Of course, it was good that we could keep Suarez. Everyone who knows his qualities on the pitch, knows that he is a player we need.”