While creating metric alert and setting up the frequency in the trigger page if more than one time needs to be added then the user has to use ‘,’ between each time (Refer Pic:1). The format to use ‘,’ is not mentioned in documentation nor written in trigger page.
So, we should add this format in documentation and create an ‘i’ button which will show the format when user hover-over to it.
Or we can have a placeholder text as ‘comma separated values’ just like we have in variables of dashboards (Refer pic:2)
Another approach can be we should show the ‘+’ button just like we are using in auto-run page (Refer pic:3)