Preheat the air fryer at 400 degrees F for 5 minutes.
While air fryer preheats, pat the cod dry with paper towels. Drizzle olive oil over cod and rub into all sides. Sprinkle with salt and pepper, and then add the chili powder to the top of the cod.
After air fryer preheats, add the cod to the air fryer basket. Cook at 380 degrees F for 10 minutes.
Melt the butter in a small bowl. Add the juice from the lime. Plate the cod, and then spoon the butter mixture over the top of the cod. (Alternately, you could just squeeze lime over the cod and not use butter if desired).
Top with fresh herbs if desired.
Notes
Cook time may vary based on your specific air fryer and the thickness of your cod.
Cod should be cooked to an internal temperature of at least 145 degrees F. You want your cod to be flaky and delicious. Don't overcook cod.