Meta has released a Mac app for Muse, its personal AI agent. Muse first launched in early September on iPhone, Android, the web and WhatsApp, and this update extends it to the Mac desktop itself, widening its reach from mobile and browser tasks to everyday computer work.
Working in the Background, Across Multiple Apps at Once
The Mac version of Muse connects to native macOS apps including Files, Mail, Messages, Calendar and Notes. It can tidy up folders, fill in forms using information it already has on hand, and put together a summary of the day's activity across several apps at once. A notable feature is that it keeps working in the background even after the app window is closed. Give it a task such as "organize that folder" or "summarize today's emails," and Muse continues the work while you do something else, reporting back once it is done.
The system runs on Muse Spark, a model Meta describes as built specifically for real-world agentic work. The architecture carried over from Muse's initial launch earlier in September remains in place on Mac: every session runs inside a dedicated cloud virtual machine called Muse Secure VM, and a separate agent named Sentinel monitors outbound network activity from within that same machine. For higher-stakes actions, such as deleting a file or sending a message, Sentinel requires explicit approval from the user before anything is executed.
Full Disk Access Is Opt-In, With Limits by Default
Broad access to the Mac itself is the obvious concern with an agent like this, and Meta has kept it limited by default. Full Disk Access is opt-in and can be granted or revoked at any time from Settings, and a public bug bounty program is in place for security researchers who find vulnerabilities. The Mac app is currently a free release for users in the United States, capped at 100 million tokens of usage per week. Meta has not open-sourced Muse; it remains a hosted, Meta-run consumer service.
Rival AI agents that take direct action on a user's computer are moving just as fast. Instinct, valued at around 10 billion dollars, and the conversational agent Poke have both been expanding their own feature sets. In the same week as the Mac launch, Muse and Instinct each rolled out voice-calling capabilities. As AI agents shift from simply answering questions to actually carrying out tasks, the desktop has become the next battleground companies are racing to claim.
Summary
Meta has released a Mac app for its Muse AI agent, extending it beyond mobile and the web so it can act across Files, Mail, Calendar and other native macOS apps. The safety design introduced at Muse's initial launch — isolation inside a virtual machine and oversight from the Sentinel agent — carries over intact, while the scope of what Muse can do has grown considerably. As competitors push into the same territory, further feature expansion and wider regional availability, including Japan, will be worth watching.
