This is one of the most beautiful little buildings I can conceive of. I want to draw and drink hot tea out here in the pouring rain, listen to it splashing on the ponds... (I found this picture in a gardening magazine one time. I don't know which magazine, didn't take a picture of the credits, just the hut.)
An opuscule can be a small, detached retreat set at the edge of the garden. A fine place for reading, painting, composing or just getting away from it all. An opuscule can be an open-air structure nestled in the woods to take in the view. Perhaps a small wood-burning stove or fireplace adds just the right amount of heat for comfort.