Can you explain what the issue is with nullability here? Is the concern that someone's code returns null in normal circumstances but doesn't document that well, so you don't check if null? Cause if it's an error situation, one way or another some exception has to be thrown.

Why don't you have any coding standards? If you're working with agents in particular, catching and enforcing this stuff should be easier than ever.

Null Analysis can be checked and enforced by the CI.