Rewrite and proofread text in any app

Select some text, right-click it, and near the bottom of the menu there is Writing Tools. It can proofread the text, summarise it, or rewrite it in a friendlier, more professional or more concise tone. The result replaces your selection, and you can undo it with ⌘ + Z if you prefer the original.

The part people miss is that this is a system service, not a feature of one app. It works anywhere macOS draws a standard text field: Mail, Notes, Messages, a form in Safari.

⌘ + A selects everything in the field first, which saves dragging across a long message.

It needs a Mac that supports Apple Intelligence, with the feature turned on in System Settings → Apple Intelligence & Siri. Treat rewrites as a draft rather than a result: reread before you send anything.