That was set out plainly in the invitation emailed to potential candidates, which stated: "Must have coached one of the following in the last 12 months - Super Rugby for a New Zealand franchise, Heartland/ITM Cup, All Blacks, a New Zealand national team or completed a minimum of three years cumulatively in any of these roles. This 'qualification' to remain valid for up to five years from the date the coach ended their involvement with the New Zealand team."
However, NZRU chief executive Steve Tew has said the criteria might not apply as strictly to assistant coaches, so Kirwan, who is also said to be interested in a role with England, might not be completely out of the frame.
Several high-profile coaches in New Zealand, including Todd Blackadder, Jamie Joseph and Colin Cooper had ruled out applying for the job.
Hansen is likely to choose Ian Foster and Mick Byrne as his assistants, with friend and business partner Aussie McLean, who helped coach Samoa at the recent World Cup, also in the mix.
A former coach of Wales, Hansen has been an assistant All Blacks coach since 2004. Former fellow assistant Wayne Smith will help coach the Chiefs in next year's Super Rugby competition.