Or "what is your name"? Seems like spam is always trying to hide the actual identity of the sender. "This is Jack from the warranty department"? Yeah, sure you are. Whose warranty department? They won't get specific because they know that if they do, I'll know that I don't know these people. They're trying to pretend that they're someone that I already have a relationship with, but in doing so they get vague.

And, "The vehicle warranty is about to expire"? Yeah, which vehicle? They won't get specific because they don't know.

I don't know how to implement it, but a "who are you specifically?" filter would eliminate a lot of my phone spam.