Animals exhibit remarkable flexibility in their behavior. Such adaptability is tuned by integrating evolving physiological internal states, external contexts, and previous experiences. In this review, we aim to summarize recent findings on the circuit mechanisms of the reciprocal modulation of sensory processing and behavior through internal states, external contexts, and behavioral actions. We discuss how metabolic states reconfigure odor valuation, how social contexts generate motivational states that redirect action selection, and how behavioral execution recursively modulates sensory perception to drive adaptive decision making, toward a multiscale mechanistic framework of the interplay between states, contexts and actions.