Prep the drumsticks: Pat the chicken dry with paper towels.
Removing moisture helps the skin crisp and the rub stick.
Mix the rub: In a small bowl, combine smoked paprika, garlic powder, onion powder, cumin, chili powder, cayenne (if using), salt, pepper, and brown sugar. Stir to break up any sugar clumps.
Oil and season: Place drumsticks in a large bowl. Drizzle with oil and toss to coat evenly.
Sprinkle the rub over the chicken and massage it in so every side is covered.
Preheat the air fryer: Set to 380°F (193°C) for 3–5 minutes. A hot basket kick-starts the browning.
Arrange in the basket: Place drumsticks in a single layer with a little space between them. Cook in batches if needed to avoid crowding.
Air fry, flip once: Cook at 380°F (193°C) for 24–28 minutes, flipping at the 12–14 minute mark.
Drumsticks are done when the internal temp hits 165°F (74°C) and juices run clear. If you like extra-crispy skin, go 2–3 minutes longer.
Rest and serve: Let the chicken rest 3–5 minutes to keep it juicy. Finish with a squeeze of lime and a sprinkle of herbs if you like.