I'm trying to insert and name a new worksheet into an existing Google Sheet using java-script in the browser.
When using the Spreadsheets V3 API in Google's OAuth Playground to try to Insert a Worksheet (VIA the "Insert Worksheets" operation), I get an error 415: "Content-Type application/json is not a valid input type."
I've tried using all the default content-types Google provides in a drop-down, and they all result in the above error. I've been unable to find documentation for the Spreadsheets V3 API aside from what's in the OAuth playground.
Does anyone know the correct content type / how to insert a work sheet into a Google Sheet using java-script browser code?
Thanks!
Summary/Solution:
Google Sheets API v4 is the next version of Spreadsheets v3 in the OAuth playground.
The Reference section of the Google Sheets API v4 seems to be missing a lot of API details, but you can find them in the Google Sheets API v4 migration guide.

