The Argentine was dropped for the young Brazilian earlier in the season, but was drafted back into the first team after the 20-year-old picked up a metatarsal injury.
Aguero remains linked with a departure from the Etihad Stadium, with questions hanging over his first-team future at the club once Jesus makes his return.
However, Guardiola was eager to pay tribute to the 28-year-old, telling Sky Sports News: "I have said many times he is now involved [more] in the game. My feeling before was he was just waiting to score a goal because he has this quality.
"But now he is involved in the game. Not just in the defensive part where he has helped us a lot and has done all he can do but also in our process to create the chances, so no complaints about what he has done since the injury to Gabriel.
"[His attitude] was always good, from the beginning - I said that many times. We had no complaints. He is just now maybe understanding better what we are looking for but he is trying and that is what I want. After that, if he misses chances or misses other things, always you can improve but I have no complaints."
Aguero has scored 164 goals for Man City since his switch from Atletico Madrid in 2011.