I am working with Sandcastle for a while now and I am also used to find xml inline comments in the .Net Source Reference. They usually match exactly the descriptions found on msdn. 

**Since .Net 4.6 and .Net Core it seems like Microsoft creates their comments differently.**   
(Cannot find them in the .Net Source Reference anymore)  

**An example:**  

<https://msdn.microsoft.com/de-de/library/system.string.padright(v=vs.110).aspx>  

This method has a comment in msdn but I am not able to find it in the source:   

<http://referencesource.microsoft.com/#mscorlib/system/string.cs,56cb688f4f1dc9e4>

I am wondering how they are doing it right now with .Net 4.6 and how they will/are doing it with .NET Core. **Can anyone confirm and explain this to me?**

EDIT:
Since .Net Core is Open Source we should be able to figure this out. But I cannot find any information about it.  

EDIT2: Since .Net Core is Open Source I think we should have access or at least be able to get access to their internal "secret" documentation tool. How else can we further develop the .Net Core and write documentation. **Does anyone know that tool or where to find it?**