The functional detail
In the WWDC 2026 overview published by Analytics Insight, it emerges that Messages and Mail in iOS 27 receive AI suggestion icons: the on-device model analyses the text of the conversation or email, recognises actionable entities (a meeting time, a delivery address, a reply deadline), and presents them inline with a tap-to-action icon. The user adds the appointment to Calendar or creates the Reminder with one tap, without going through Siri and without manually copying text.
Difference from Smart Reply
Suggestion icons are not suggested replies to the message (already covered as Smart Reply), but actions on the content of the message itself. It's a subtle but important distinction: Smart Reply suggests what to write in response; suggestion icons suggest what to do with the information in the message. Both systems coexist in the same app.
Potential limitations
Accuracy depends on the model's ability to distinguish contexts: an email saying 'see you at 3pm' works well, but a thread with multiple times and recipients could generate ambiguous suggestions. Apple has not communicated details on how the system handles ambiguity or how users can flag false positives.