Is there any knowledge base available to check definitions for attributes for project approval ELA

Summary:

Hello Team,

I am creating a rule to check the below criteria for employee timecard:

1. Entry of hours for a day more than 9
2. Project has a billable flag

But i don't see any payload attribute for above ( for recorded hours, i see the header option for total but not for a day wise entry)

I see there are a lot of custom attributes available for the payload, is there any documentation which describer their function so that we can check what all parameters we can use?

Thanks,

Priya