Create simple TFS Extension

This is an exercise to learn about creating simple TFS extensions in the absence of clear documentation. I need the following: * C# TFS extension project that will publish a *.vsix file that will publish a TFS extension. * The extension will accept 2 arguments: a key, some text * This extension is used as a build/release step and will result in sending information to a rest API based on those 2 arguments. I would like to know how to do that to better understand how to make more advanced ones. I do not understand the documentation available or rather it is more complicated than my usual MVVM model javascript script designs.