I would answer that in a couple ways.
First, of the thousands and thousands of intergovernmental agreements that exist, a lot of them are public, some by default and some upon request. The general standard is to release things publicly whenever possible, but there are times when governments prefer not to.
I'll cite an example around the compliance of a program. From time to time, there are details in agreements about information sharing and what information is shared between levels of government. If they were made public, it could lead to potential fraud. If people can understand the program better behind the scenes, it can compromise the integrity of the program.
That's one thing. The other part is that generally when we do a release agreement, we seek provincial consent given it's a partnership. We don't necessarily oblige unless it's written into the agreement that it should be public. In this sense, an obligation to release the agreement would oblige us to release something that the province may not necessarily agree with.