Meta launches Muse Code AI agent for large code bases

Meta launched a beta version of Muse Code, an AI coding agent that tackles complex tasks across large software repositories, on August 5, 2026.

The tool can plan changes, write code and validate results, said Meta CEO Mark Zuckerberg. It handles large projects by spawning sub-agents that work in parallel in isolated worktrees, never touching the user’s working copy.

In testing, Muse Code built six features for a game simultaneously with no collisions.

Powered by the previously released Muse Spark model, the agent installs with a single command. The release aims to position Meta more competitively and affordably against rival assistants like OpenAI’s Codex and Anthropic’s Claude Code.

Alexandr Wang, Meta’s AI chief who leads Meta Superintelligence Labs, told The Wall Street Journal that for many workflows and use cases, Muse Code “can be an incredibly good option, especially from a cost perspective.”

The launch follows Meta’s June 2026 entry into the enterprise AI market with an agent for customer service and support, part of the company’s broader effort to grow its AI presence beyond its advertising business.