Muse Spark is a natively multimodal reasoning model released by Meta Superintelligence Labs in April 2026, designed as a powerful personal assistant. It accepts voice, text, and image inputs, and features two reasoning modes: Contemplating mode for deep parallel multi-agent reasoning on complex problems, and Instant mode for fast everyday interactions. The model excels at visual reasoning, coding from visual specifications, and health analytics — scoring #1 globally on HealthBench Hard — and powers Meta AI across Facebook, Instagram, WhatsApp, and Messenger.