Meta releases Muse Spark Open — 816B-parameter open-weight multimodal MoE model
Meta published Muse Spark Open, an open-weight mixture-of-experts (MoE) model with ~816 billion parameters (≈42B active per token) that accepts text, images, audio, and video and supports up to a 1,048,576-token context window. Meta says the model is optimized for agentic coding workflows (reading, writing, debugging code and tool calls); checkpoints are available in BF16 (safetensors, ~1.5 TB) and an NVFP4 4-bit format tuned for NVIDIA Blackwell GPUs.