Good on you (I don’t think so!)

You hear it all around you. “Good on this”, “good on that”, “good on you”.

Good is an adjective that describes a noun. In the usage I’m hearing (above), the usage sounds more like a verb: I good, you good, we good, etc. Where in the world of English-speaking people did this term come from? Boo! Hiss! Go to war, Miss Agnes!