All schema languages are a bit like that. You can almost always add another layer on top of the validation and screw down the validation a bit harder. The strictest validation will only be achievable using a turing complete language.
OpenAPI is probably used a bit more than json schema, but it's contextually limited to APIs (which, to be fair, is mostly what JSON is used for).
OpenAPI is probably used a bit more than json schema, but it's contextually limited to APIs (which, to be fair, is mostly what JSON is used for).