"I don't think we have to overthink this. We have to make sure he is in a good frame of mind, his body is in good shape, and then we can plan accordingly."
While announcing Stokes' new role, Key also said veteran fast bowlers James Anderson and Stuart Broad — the top two wicket-takers in England's test history — would also be available again after being controversially left out of the recent West Indies tour.
England plays test series against New Zealand and South Africa this summer, and also completes the series against India that was cut short last year with India 2-1 ahead with one test remaining.
"Before it got announced I was doing this job, I rang them up and said, 'In my opinion you're both available for selection'," Key said of the 35-year-old Broad and the 39-year-old Anderson. "I can't promise you you're going to play but you are just available for selection.
"Ben Stokes was very clear on the fact that he wants Jimmy and Broady to come back in. It will purely be done on what's the best XI to win that first test match. Nothing more, nothing less. If they are in that, which there's every chance they will be because they are two great bowlers, then they play."
Key said new head coaches would soon be hired to lead the men's test and limited-overs teams, insisting the same person cannot handle both jobs.
"It's just become a job that has become near-impossible for one coach to do," Key said. "The amount of cricket we play, with all the Covid catch-up, all that stuff, you're going to have times where you literally would be jumping on a plane to the other side of the world to coach a different format."
Getting rid of Covid bubbles for teams is expected to further ease the mental burden on players and coach staff. That should help Stokes, one of the world's best cricketers in all formats, as he settles back into the swing of a hectic cricket schedule.
"He cares about the people around him, he has understanding for why people struggle, he has understanding for why people might not be feeling right," Key said. "All those traits, along with a very good cricket brain, make him the standout choice."
Stokes said Root will "continue to be a key ally for me" as he takes on the captaincy.
"I want to thank Joe for everything he has done for English cricket and for always being a great ambassador for the sport all across the world," Stokes said. "He has been a massive part of my development as a leader in the dressing room."
Stokes was born in Christchurch, the son of former Kiwis rugby league player Gerard Stokes, and moved to the north of England aged 12 when his father was appointed coach of a domestic rugby league team there.
