The NMDC project at SourceForge http://nmdc.sourceforge.net/ intend to document the NMDC protocl as well a pooling all relevant NMDC information.
The base document http://nmdc.sourceforge.net/NMDC.html describes commands and everything else that is protocol specific. The SVN contains mirrors to other sites that also document the protocol, but the base document should have all the necessary information. If the document do not, please comment what is missing and where available information is.
Please note that the document uses literal “<” and “>”, so things like "$MyINFO " will not appear, they will simply be “$MyInfo nick”.