How can we verify purchase code in my product

I want to sell my plugin and theme on Envato. I want to verify purchased code. Do I have to verify purchase code using API or Envanto will verify on my Behalf.

Thank You,
Accrete Team

As far as I know, there is no official way from Envato but there is a script that I use to verify purchase codes which is made using the Envato API:

I’m new here, but I thought purchase code verification is done through the API.