Magic Compose tool will send up to 20 previous messages to Google's servers, which will generate suggestions to start or reply to a conversation, or to rewrite a drafted message in different styles.
Magic Compose tool have seven different styles that rephrases the text in: Chill, Excited, Formal, Lyrical, Remix, Shakespeare, and Short.
– The feature is specifically designed for RCS (Rich Communication Services) within the Messages app