my external server app is connected to Zoho CRM via standard REST (happy to see v3 btw!) and the connection is secured / auth'd via OAuth as suggested by the docs.

recently I learned that one could authorise external calls to CRM custom functions via custom API key rather than OAuth, i. e. by setting auth_type=apikey: https://www.zoho.com/crm/developer/docs/functions/serverless-fn-apikey.html

while suspecting what the answer might be, I wonder if there is a way to access CRM REST endpoints  (e. g. GET contact) without OAuth? OAuth is rather cumbersome for server to server communication as one has to manage refresh tokens etc.