What must the agency tell you?
At a minimum: why the proposal was not successful, how it performed against the criteria and any pre-conditions, its relative strengths and weaknesses, the relative advantages of the successful proposal, and answers to the supplier’s concerns and questions. The information must help the supplier improve future tenders; that is the stated purpose, not a courtesy.
What the agency must not do is disclose another supplier’s confidential or commercially sensitive information. You will not get the winner’s price, methodology, or margins. Ask for strengths and weaknesses against the criteria and you will get a useful answer. Ask for the competitor’s file and you will get a refusal that tells you nothing.
When do you ask?
Promptly after the award notice. Rule 30 requires agencies to inform unsuccessful suppliers of the decision, and the debrief clock runs from there. The Rule requires the debrief within 30 business days of the contract being signed by all parties, or 30 business days of the request, whichever is earlier. Do not wait for the signed contract to ask. Ask on the notice.
The method follows the procurement: phone, email, letter, or meeting. Match the complexity. A short RFQ deserves a short call. A multi-year services RFT deserves a meeting with someone who can hear criticism without defending the last draft. Reusable neutral wording is on the debrief request letter, written for Australian practice, usable as phrasing, not as a New Zealand statutory form.
What about secondary procurements?
It is good practice for agencies to debrief secondary-procurement losers who ask. Good practice, not the same must; frame the request accordingly and keep it short. Panel members who never ask never learn why the call-offs keep going elsewhere.
What does this mean for the bid/no-bid call?
Use the debrief on the next gate. If the weights sat outside what you do, that is a strategy fail for week one; write the no-bid rule for that buyer now. If a pre-condition was missed, that is a process fail; fix the day-one read. If the winner’s advantages were evidence you cannot match, stop bidding that buyer’s work in that category until the evidence exists. Record one correction in lessons learned, with a follow-up date. The Australian process, for cross-border readers, is debriefs under Australian rules. Keep the contact clean throughout; probity does not end at award.