The User API (Javadoc)
The user API (application programming interface) is a collection of Java classes and methods that helps you interact with channels and the message that is being processed. It also provides helper methods for common tasks such as date formatting.
Wherever you are editing JavaScript code in Mirth® Connect, you can view the API by selecting the View User API function in the Other panel, which is available on all Mirth® Connect Administrator views.
You can also right-click/command+click in the text area of any JavaScript Editor, and on the drop-down menu, select View User API.
The Javadoc appears in your default web browser, in which you can select classes to view their method signatures and descriptions.