Meta has launched Muse Code in beta, introducing a new terminal coding agent designed to compete with developer tools including Anthropic’s Claude Code and OpenAI Codex. Powered by the newly released Muse Spark 1.2 model, Muse Code can plan software changes, write code and validate its results across large repositories. Muse Spark 1.2 is a coding focused update to Muse Spark 1.1. Meta also trained Muse Spark 1.2 alongside Muse Code to improve how the model works with the agent’s tools, planning system, context management and subagents. During one test, Muse Spark 1.2 used Muse Code to optimize GPU kernels through more than 1,000 tool calls over sessions lasting as long as 24 hours.