This design is functionality. It added a small container in the bottle cap and you can put pills inside.Therefore when you drinking water,you will know that you need to take pills.But i think it can put other small items inside the small container.
Capsule Carafe ｜ The Capsule Carafe automatically opens as your pour in any direction. In its upright position, the lid stays closed to keep your water fresh. Ice cubes, lemon slices, and fruits are also held back while pouring.