While assisting employer clients with settlement negotiations on a conclusion of employment, I often advise not to simply agree to do a letter of reference; but instead to get agreement on the exact content of that letter at the initial time of settlement.  The reason for this is you do not want to settle the major money issues and be left arguing about wording in the letter of reference later.

The quote below is from a relatively recent Ontario Arbitration award, which essentially allowed a grievor employee to back out of a settlement because agreement was never reached on a letter of reference.

If you have agreed to provide a letter of reference as part of a settlement, this case serves as a vivid reminder that you should craft and get agreement on the content of that letter at the time settlement is reached, not later.