Need help creating custom actions in codeBeamer

I am  currently working on a project in codebeamer and I need to create some custom actions. I am new to this and could use some guidance on which APIs or methods to use some sample code to get started. I am struggling to find the logic for existing actions within the codebase or documentation. Can anyone help me 

on where I can find the logic for existing actions and  how they are implemented?

Thank you for your time!

Regards,

DK.