Theme extension App Block activation

[gagarwal]

Hi,

I am writing a theme app extension which has some app blocks and I want to activate them on certain areas like above “Add to Cart” button in product template automatically. While I read that we can a provide a deep link to merchant to add the app block in theme editor to a section and save, I also see that apps automatically activate the app block without needing merchant to do anything. But I cant find any clear documentation or articles around it. Would somebody here know how that is done? Can you please share? Many thanks in advance.