How do batching endpoint query parameters work when searching by internal ID or unique prop. values?

Hi there HS community!I have a question regarding ‘batching’ using hubspot’sAPIs. I’ve come across this at several endpoints:
Examples -
Read a batch of objects by internal ID, or unique property values (Associations)
Read a batch of contacts by internal ID, or unique property values (Contacts)
My question is simple…the documentation doesn’t seem to define these 2 query parameters very well or show how to use them even in their ‘blank examples’ (idProperty // inputs)
Let’s say i want to make a POST request to the contacts endpoint above: idProperty….is this the internal name of a property (example in my screenshot) and inputs what is that? Is that where i’m specifying the value(s) of the idProperty in question or are these not related? An example of any definition or explanation of how to use this would be great! Especially if i want to search by more than one unique value!
Also I’d really like to know the limitations of searching by a unique property value…like can i use any operators? i,e, hs_lastmodifieddate > UNIX milisecond timestamp ?

Hi @Bramos423

Thank you for reaching out.

I want to tag some of our experts here - @Bryantworks @Indra do you have any thoughts for @Bramos423 on this?

Thank you!

best

Tiphaine