Preheat oven to 350 degrees F (175 degrees C). Line 24 muffin cups with paper liners.

Beat pumpkin puree, water, and eggs together in a bowl until smooth. Stir cake mix into the pumpkin mixture until you get a smooth batter. Gently fold chocolate chips through the batter. Spoon batter into prepared muffin cups.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 15 minutes. Cool in the pans for 10 minutes before removing to cool completely on a wire rack.