Then the problem is the schema being under specified. Take the classic pet store example. It says that the I’d is int64. https://petstore3.swagger.io/#/store/placeOrder

If some API is so underspecified that it just says “number” then I’d say the schema is wrong. If your JSON parser has no way of passing numbers as arbitrary length number types (like BigDecimal in Java) then that’s a problem with your parser.

I don’t think the truly truly extreme edge case of things like C not technically being able to simulate a truly infinite tape in a Turing machine is the sort of thing we need to worry about. I’m sure if the JSON object you’re parsing is some astronomically large series of nested objects that specifications might begin to fall apart too (things like the maximum amount of memory any specific processor can have being a finite amount), but that doesn’t mean the format is wrong.

And simply choosing to “use string instead” won’t solve any of these crazy hypotheticals.