Three short lines give us a small, ordinary scene: someone sits in a park with a glass of wine, a newspaper in hand, while a dog dances nearby. That's all that happens, and the poem seems to like it that way.
The speaker doesn't say how they feel, but the mood is easy to read. There's a lazy contentment here. The wine suggests the day is unhurried, and the paper is something to glance at rather than study. The phrase "as I look / over the paper" is the nicest touch. The line break makes the eye lift above the page, the way a person does when something more interesting pulls their attention away from the news. The dog is the real event.
"Dancing" is a playful choice. It turns whatever the dog is doing into something joyful, which suggests the speaker is watching with affection and amusement. The poem is quiet and relaxed, a brief moment of pleasure noticed and left alone.