The developer guide contains all the information needed to be able to make an extension to the Argus Codewatch Eclipse Plug-in. This can be either a Codecheck or a Quickfix.
The sourceforge.net CVS contains all the sourcefiles of the Argus Codewatch Eclipse Plug-in.
If you are using Eclipse (as you probably do), you can also import one of the following project set files:
Coverage Reports of unit tests for the Argus Codewatch Eclipse plug-in source is generated using Clover and Easymock.