The plug-in spy aims to provide a simple tool to introspect Eclipse in terms of what a plug-in developer would find useful. Simply hit ALT+SHIFT+F1 on what you're looking at, and Plug-in Spy will be presented to you with relevant information. This tool is part of the Eclipse Incubator project. For a complete description of Eclipse incubation please read this.
Note, the Plug-in Spy has graduated and will be in the Eclipse 3.4 release.
Bugs and Feature RequestsWe use the Eclipse Bugzilla System for tracking issues with the Plug-in Spy Incubator project.
Accessing Source CodeSince Plug-in Spy has graduated from incubation, it's located in the org.eclipse.pde.runtime plug-in in CVS.