But you can do automatic validation fairly easily with JSON Schema. You don't need to choose a binary format to get validation. The principle benefit is that y

But you can do automatic validation fairly easily with JSON Schema. You don't need to choose a binary format to get validation. The principle benefit is that you can use the schema to define the data format, which means you can pack the data in more tightly (you don't need a byte to say "this is an object" if you know that the input data must be an object at this point). That's a big benefit in certain situations, but if you're using this sort of stuff just to get validation then you're probably better off using JSON Schema and having a wire transfer format that you can read easily without additional tools.