Muse Spark 1.3 is a multimodal reasoning model from Meta built for long-running agentic, multi-agent, and coding workflows. It is designed to maintain context across extended tasks, reason through conflicting information, and ask for clarification or confirmation when required, while keeping execution concise.  With a 1,048,576-token context window, Muse Spark 1.3 is well suited for large codebases, lengthy documents, complex multi-step workflows, and tasks that require sustained reasoning over many interactions. It supports text, images, video, PDFs and other files as inputs and returns text.