I created a C# wrapper for the SenseApi (the one that the Web Client uses) that you can use in your own C# projects. You can find it as a Nuget package (SenseApi) in Visual Studio. You can also find the source code here: GitHub - Frankwin/SenseApiWrapper: Wrapper for the Sense (Energy Monitor) API
Feel free to submit pull requests for any contributions you want to make to the project. I’ll try to continue to update it as best as I can if new things happen with the API.