Caldwell spent three years (2009-2011) with the Indianpolis Colts (26-22 record) and then four years (2014-2017) with Detroit (36-28 record).
Caldwell guided the Lions to the playoffs two of the last three years, but the team fired him after failing to make the playoffs his last season.
Pagano was a guest on the "Rapsheet and Friends" podcast and discussed his hope to return to the sidelines armed with experiences.
"Knowing what I know now, having a chance to sit back and reflect and evaluate a lot of things that we did both good and bad, now you have an opportunity to hopefully -- if you have another opportunity, whether it's a head coach, a coordinator or assistant coach, it doesn't matter," Pagano said. "I just love coaching. I love competing. I love the players. I love the coaches. I love the camaraderie, the competition, games, that's what you really miss."