title: How to add usage hints for our custom methods and properties in Xcode?
body: <p><img src="https://i.stack.imgur.com/oXl7a.png" alt="Code completion with usage hints at the bottom"></p>
  
  <p>In the attached image Xcode is showing usage hints (two lines at the bottom) for its classes. Similarly, is that possible to have my own hints for my custom class methods and properties?</p>