I didn't thought about it yet, but right now when you put =SUM(A1:A10) into cell, and GET (or POST) it via API, you will get the result (sum of the column 1-10)

I didn't thought about it yet, but right now when you put =SUM(A1:A10) into cell, and GET (or POST) it via API, you will get the result (sum of the column 1-10). So, it'll be working with sheets the same way. ex. when you put =Sheet2!A1 and get that via API, you will get the value of A1 cell in Sheet2.