Meta's Muse Spark is its first frontier model and its first without open weights

Meta released Muse Spark, its first frontier model and its first AI model without open weights.

The model is multimodal, supports tool use and visual chain-of-thought, and offers a Contemplating Mode for parallel agents.

Meta rebuilt its pretraining stack and used large-scale RL, saying Muse Spark matches Llama 4 Maverick with far less compute.

Independent tests scored Muse Spark 52 on an Intelligence Index and show strong multimodal and health results, while agentic and coding tasks lag.