[Vuejs]-Validation with Joi in Axios call not giving correct response

So after many hours of debugging and playing around, I realized that the err object that I catch is an object whose structure I didn’t know. Specifically, it has a response component. err.response.data got me what I want.
I would still like to know if anyone has any ideas how could I find something like this out, I didn’t see anything that pointed me in this direction in the documentation and I guess the logging wasn’t what I expected.