Postman test script for json schema validation failing for some custom format types in json schema

Postman Schema validation using the following method is failing with validation error in tests. The schema is part of pre-request script which saves the schema object as a collection variable.

pm.test("Validate response schema", function () {"create_key_schema"));

Similar way this also occurs for another type “uint8”. Is it like, jsonSchema validation in postman is inclined only for Javascript based backend APIs?

Details (like screenshots):


Error Observed: