I am currently using Sandcastle, Doxygen, and JavaDoc to generate documentation for code I have written. Is it possible to document XML schemas using these packages? If not, are there any (preferably free!) packages which can do this? I could write the documentation myself as an extra conceptual topic within Doxygen or Sandcastle, but I would rather a tool did it for me!
An example would be (although I am no expert at XML Schema!):
/// <summary>Top Node</summary>
<xs:element name="TopNode">
/// <summary>Child Node</summary>
<xs:element name="ChildNode" type="xs:string"/>
</xs:element>