Hume AI has built something different: an AI that can detect emotional expression in voice and adjust its own responses accordingly. The Empathic Voice Interface (EVI) listens for vocal cues - stress, excitement, uncertainty - and adapts its tone, pacing, and word choice in real time to match the emotional context. The API enables developers to build voice applications with genuine emotional intelligence: mental health support tools that respond to distress, customer service bots that de-escalate frustrated callers, educational tools that recognize when a student is confused. The model is built on Hume's research into expressive communication. For developers building voice AI applications where the emotional quality of the interaction matters, Hume's empathic AI capabilities represent a category that no other voice API currently addresses.