If you are developer and you want your application to be scriptable, writing an AppleScript dictionary is fast and easy with Sdef Editor.
Sdef Editor can create and edit sdef xml files. Sdef file format is the native Mac OS X AppleScript Terminology format in Mac OS X.4 and later, but it can also be exported as Cocoa Terminology (.scriptSuite and .scriptTerminology files) or “aete” resource file for older Mac OS X versions.