1. at_server_spec
2. verbs
3. Update
4. usage method

Update class

1. Constructors
2. Update
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. dependsOn
8. name
9. noSuchMethod
10. requiresAuth
11. syntax
12. toString
13. usage
14. Operators
15. operator ==

@override
String usage() {
  return 'e.g update:@alice:location@bob sanfrancisco';
}