Get information about actions in Automator on Mac
Each action in the Automator app has its own description that tells you what it does.
In the Automator app on your Mac, click the action in the Library. A description of the selected action appears in the bottom-left corner of the Automator window.
The description may contain the action’s required input, output and result. Although some actions require no input or output, others have very specific input requirements such as a specific type of file from a previous action. For example, an action that requires a graphic file for input can only follow an action in the workflow that has a graphic file as output.