You can add new APIs in 3 different places:
1. Add External API
If you use an external API, a new file will be created and your functions will be placed within that file.
Use this option if the functions you are creating will be used by more than one Custom Panel.
2. Add Internal API
If you use an internal API, the functions will be created within this Custom Panel, in an \"api\" tag. The functions will be accessible to all scripts in this panel.
Use this option if the functions you are creating will be used by multiple scripts within one Custom Panel
3. Add Function
If you use a function, that functions will be created within this script. It will only be accessible within this script.
Use this option if the functions you are creating will only be used by this script.