json doesn't have ints, it has Numbers, which are ieee754 floats. if you want to precisely store the full range of a 64 bit int (anything larger than 2^53 -1) then string is indeed the correct type
json doesn’t have ints, it has Numbers, which are ieee754 floats.
No. numbers in JSON have arbitrary precision. The standard only specifies that implementations may impose restrictions on the allowed values.
This specification allows implementations to set limits on the range
and precision of numbers accepted. Since software that implements
IEEE 754 binary64 (double precision) numbers [IEEE754] is generally
available and widely used, good interoperability can be achieved by
implementations that expect no more precision or range than these
provide, in the sense that implementations will approximate JSON
numbers within the expected precision. A JSON number such as 1E400
or 3.141592653589793238462643383279 may indicate potential
interoperability problems, since it suggests that the software that
created it expects receiving software to have greater capabilities
for numeric magnitude and precision than is widely available.