What you're actually saying is that when you use the standard language bindings for a protobuf parser, the type safety is as built in as your language. JSON ha

What you're actually saying is that when you use the standard language bindings for a protobuf parser, the type safety is as built in as your language. JSON has a limited set of types. There is object, array, string, number, boolean, and null. That's it. JSON Schema adds to that by providing definitions of types that build on those basic JSON types.