Meta debuts proprietary frontier model Muse Spark after Zuckerberg’s $14.3 billion Scale AI deal, but engineers still favor Claude

Mark Zuckerberg put $14.3 billion into Scale AI, bringing in Alexandr Wang as Meta’s Chief AI Officer and delivering Muse Spark, the company’s first proprietary frontier AI model. Meta has kept Muse Spark closed, citing biosafety risks, and is positioning it inside Facebook, Instagram and other products rather than as an open developer platform. Even so, the model is seen as trailing rivals such as Claude and Gemini, and Meta has yet to rebuild developer confidence. The company remains heavily dependent on advertising and is testing subscriptions, while its shares are down 18% over the past 12 months.