Stencil is an Xcode plugin that provides the ability to create custom file templates and use them in your project to create new files. It’s intended to save you time while making it easy to extend a project in the future: for you, next week; for your current colleagues; and especially for people that might inherit a project from you in the future.
Once you’ve used Stencil to create a custom template, you can create new files based on this template. The new files can include Objective-C headers and implementation files, interface builder files (.xib and .storyboard), as well as Swift source files.
It really adds benefit when there’s a particular class that you commonly subclass, especially if the new subclass requires an interface builder counterpart.
Of course you would want to document your project to explain that you have defined custom templates, which can be used with the Stencil plugin. But if one of your co-workers doesn’t have the plugin, then it doesn’t matter. No harm done, it just means they won’t reap the benefits. And you can spend longer on your tea break, while they’re spending longer doing things manually!