Introducing Muse Spark Open, The Most Capable US Open‑Weight Model to Date

Meta released Muse Spark Open, an open-weight multimodal model with 816B total parameters (42B active) and a 1M-token context window, optimized for coding and agentic tasks.

The model weights are available for download on platforms including Hugging Face, Amazon SageMaker AI, and Google Cloud Model Garden, and it can run on two Apple M5 Ultra Mac Studios using the MLX framework.

Meta released the weights under the Muse Model License with limited commercial terms.