Meta is testing a dedicated Mail tab inside its Muse AI agent, a feature that would give the assistant its own page for handling email, according to TestingCatalog, which said it spotted the unreleased interface on September 18. The publication reports it is still unclear whether Muse would get its own address and correspond independently, or whether the tab would simply organize messages Muse already handles through a user’s connected personal accounts, access that today requires selectable read and send permissions, with sending needing separate approval. TestingCatalog views the separate mailbox as the more plausible reading, but it says the leaked design alone does not settle the question.
The discovery follows Muse’s climb to the top of the US App Store chart, per the same report, along with a recent macOS release built with computer-use features. A dedicated inbox would also complement Meta’s planned Shared Agents tool, which would let businesses turn agents into reusable templates, since an agent handling correspondence needs somewhere for its owner to track that activity. Meta hasn’t said when the Mail tab could ship, and TestingCatalog notes the company’s public description of Muse’s email access does not resolve which version is coming.
Per TestingCatalog, which reported spotting the unreleased interface on September 18, 2026.
