Meta's Muse Spark Open arrives in SageMaker JumpStart — 816B total parameters, 42B active per token

Meta's Muse Spark Open, which Amazon describes as a coding-optimized open-weight model, is now available in Amazon SageMaker JumpStart, the machine-learning hub of SageMaker AI, Amazon says. It is a reasoning model that accepts text, images, documents, audio and audio-video as input and returns text. Its architecture is a mixture of experts with 816 billion total parameters, of which 42 billion are active for each token. Keep those two figures straight. A model labelled 816B does not run 816 billion parameters of work on any single token; the active count is 42 billion, roughly a twentieth of the total. Total capacity and per-token cost are different quantities, and for anyone weighing deployment, that gap is the interesting part.