Looks just fine to me :) ... but more importantly this is consistent with other occurrences in the tutorial. The `@` gives an immediate visual cue that this is an attribute name or attribute type.

This is also **consistent** with other documentation: e.g., [Chapter 2 of Dart: Up and Running](https://www.dartlang.org/docs/dart-up-and-running/contents/ch02.html) refers to

> You can use the `@override` annotation to indicate ...

rather than just "You can use the `override` annotation to indicate ...".