@joffreyjaffeux That’s not the same “API” that @Umer_Mirza was asking about. I put “API” in quote because it may not exist?
The User API keys specification RFC talks about the use case of allowing users themselves the ability to request and API key so that a third party developed app may perform actions on their behalf. You would never want to give a third party your site API key because they would have full access.
I would ask this question in User API keys specification but that topic is closed. Does the API that @sam proposed in that post actually exist or not?