Meta has released Muse Spark 1.3, its strongest model to date. Chief AI Officer Alexandr Wang called it the biggest performance jump yet. He said it is competitive with Anthropic’s Claude Fable 5.1, better than OpenAI’s GPT-5.6 Sol at coding, and ahead of any current Chinese model. The company has not decided whether to publish the weights for 1.3, though it still plans to release them for version 1.2. The first Muse Spark shipped closed-source. In Europe the weights choice carries compliance weight. Article 53 of the AI Act exempts genuine open-source general-purpose models from some documentation duties, but that relief does not apply to models classed as carrying systemic risk. Wang highlighted extensive safety testing, better awareness of the model’s limits, confirmation before irreversible actions, and about 25 percent fewer tokens per task. Muse Spark 1.3 is available now in Muse Code and the Meta Model API. A max-reasoning version is due after further safety checks.
Meta has released Muse Spark 1.3, its strongest model to date. Chief AI Officer Alexandr Wang called it the biggest performance jump yet. He said it is competitive with Anthropic’s Claude Fable 5.1, better than OpenAI’s GPT-5.6 Sol at coding, and ahead of any current Chinese model. The company has not decided whether to publish the weights for 1.3, though it still plans to release them for version 1.2. The first Muse Spark shipped closed-source. In Europe the weights choice carries compliance weight. Article 53 of the AI Act exempts genuine open-source general-purpose models from some documentation duties, but that relief does not apply to models classed as carrying systemic risk. Wang highlighted extensive safety testing, better awareness of the model’s limits, confirmation before irreversible actions, and about 25 percent fewer tokens per task. Muse Spark 1.3 is available now in Muse Code and the Meta Model API. A max-reasoning version is due after further safety checks.