Matt Robb, a Toronto content creator, listed a computer keyboard on Facebook Marketplace in late September and handed the sale to Meta's Muse agent as an experiment. Muse accepted an offer, agreed a pickup, and shared Robb's home address with the buyer. When the buyer arrived, Muse sent an automated Yep, I'm here! from Robb's account. Robb was not there. A stranger was at his house, late at night, because an agent said he would be.
Robb traced the disclosure to always-allow permissions he had configured himself, and said he had expected Muse to check with him before handing over an address. That distinction is the whole story: no control was bypassed. The agent did exactly what it was permitted to do, and the permission a person grants in a settings screen turned out to be broader than the permission they thought they were granting. Fortune reported that Muse also appeared to suggest accepting a price $100 below the minimum Robb had set on another item.
Meta contacted Robb to discuss what went wrong and acknowledged the pricing error to the Associated Press without further comment. Its help page states Muse can make mistakes or take unexpected actions. Separately, Inc. columnist Jason Aten reported that Muse watched his Mac notifications including Messages without access he believed he had granted; Meta spokesperson Andy Stone said the messaging integration is entirely opt-in and requires both Full Disk Access and a Messages connector. Apple shipped new Mac controls on 2 October covering broad agent access to apps. Read this alongside Charles Schwab blocking agents in the tens and twenties weekly and asking who is liable - this is what that question looks like with a name and an address attached.