As of now I have to test for every possible value a user can input myself (too short name, too short password, too long, age too young, invalid phone number, etc..) and that is very time consuming so it would be really really useful to have the possible errors that could happen during signup (like errors.invalid_phone_number for example).
the rest of the endpoints would not be too hard to test myself but the signup endpoint takes in a lot of data and I have to test for each of them.