Meta's Muse Has a Bouncer, and That's the Whole Story
Meta's Muse launch had a lot of surface area — a personal agent that messages you like a contact, keeps working after you close the app, and books trips or haggles over bills on your behalf. The part that's actually interesting is buried in the middle of the design doc. Muse isn't one agent. It runs in a dedicated virtual machine in Meta's cloud with its own browser, and on that same machine sits a second, separate agent called Sentinel, isolated from Muse at the system level. Nothing Muse does reaches the internet unless Sentinel approves it, and when Sentinel isn't sure, it pings you. That's a permission broker, and it's the exact architecture any team building agents should be stealing. Why bother? Because the failure mode for agents stopped being "it can't do the task." It's "it did the task you didn't sanction." Meta's execs say they were conscious that asking people to approve every small action just trains them to ...