Person A: "Would you like to try some of my new recipe? It's Guacamole Crab Dip."
Person B: "No, I'm good"
Person A (on the phone): "Hey, Jenny. You've been studying too hard. How 'bout I swing by your apartment and give you a back rub?"
Jenny: "No. I'm good"
Person A: Do you want to go down to the Creepy Crawl and see The Wheezing Coughers?
Person B: "No thanks, I'm good."
I was walking to the grocery store and a man selling bootlegged movies, says,"Ms., you want to check out the hot movies?..They only goin' fa five dollas..?"...My reponse is,"Naw man, I'm good."
Meaning a drug dealer has resupplied his drug supply and is ready to sell. Drug dealers will usually text their most frequent buyers saying "I'm good" so they know that they have resupplied and are ready to sell.
Dealer: I'm good
Buyer: Okay can I get a dub?
Dealer: Yeah I'm at my crib.
Buyer: Okay!