Include Assembly Version Information in .NET Documentation – Innovasys Support

You can use the built in Metadata elements to add the version number of the content you are documenting:

%%AssemblyVersion%%
%%AssemblyFileVersion%%

These meta data elements can be added in any content for the assembly in order to output the version information.

Documentation for those elements, along with many others, can be found in the Document! X online help:

Let me know if you need any further information at all.