Harvey said he has no unfinished business and is happy to take a back seat.
"I've had my time as a senior coach," Harvey said on Monday.
"I'm more content now to really sit in on a football department and make sure that it operates the right way from what I've learnt as a senior coach.
"I'm happy doing that. I coach the way I know and operate."
Harvey held the reins as senior coach of Fremantle between 2007-2011, before taking up an assistant role at the Brisbane Lions for two seasons, which included a stint as caretaker coach following the dismissal of Michael Voss.
He said he was eager to re-enter the assistant coaching ranks after 12 months out of the game.
"It's good to be back home and working with the club that I've always been indebted to based on your playing career," he said.
"I sat back from afar and kept an eye on the place, (I'm) only too happy to come back and help out, and make sure this club moves on.
"I deliberately, this year, stepped away from football just to have the mental break, I'm only too keen to get back involved and work with players on a daily basis."
Harvey said the relationships he formed during his early career at the Bombers lured him back to the club.
"People that I've known in and around the footy club for the last 30 years, some of these people have also been around for 50 years," he said.
"In fact, some of the players are still here when I first started coaching under 'Sheeds'.
"There's all that attachment and I guess, in some way, shape or form, I was always going to finish up where I started."
Harvey replaces Simon Goodwin, who crossed from Essendon to join Melbourne as Paul Roos' eventual successor.
Harvey will work alongside fellow assistant coaches Matt Egan and Nathan Bassett.
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