For a one-time, during-named-storm, leak I would NOT want the builder to start trying to fix things.
that's my point about it being possible to make things much worse for nothing.
I would absolutely put the builder on notice that a leak was detected, and include pictures in the documentation, but you could easily wind up with stucco patches, mis-matched paint, janky caulk joints, etc. and STILL wind up with leaks in the next named storm.