Hello,
I’m looking to create an app that will generate JSON for a structure that will then be transformed into web page blocks. For ex.: image, text, carousel etc.
So I need to teach which blocks can be used, which attributes they have, and in which cases they should be used. The context is too long. Also, I have plans to provide a lot of examples.
Maybe anyone can give me some hints or resources about what approach to select for this use case?
Welcome to the community!
Our company happens to be building the exact same thing 
(although probably for a different market)
There are quite a number of engineering challenges there, but I would say the core tenet here would be to divide and conquer.
While I don’t think it’s wholly impossible with custom GPTs, you’ll likely need to develop a number of tools while still doing a lot of handholding to help it along. 
Why not just use Markdown and then use a formatter? I use this exact strategy with my AstroJS sites to run autonomous blogs.
Ideally you would have your “raw” content as JSON and then write a script to convert it to markdown.
This is exactly how I have my pipeline and it works great. From writing the content, to filling images and citations
You can use JSON Schema to define block structures and attributes. For rendering, consider using a component-based framework like React or Vue to dynamically generate blocks. A UI builder for drag-and-drop functionality could also help. Check out resources like JSON Schema and tutorials on React/Vue components for guidance.