custom field get_userinfo

Method: get_user_meta

It needs ‘user_id’. ‘meta_key’ var is optional.

https://localhost/api/user/get_user_meta/?cookie=COOKIE-HERE&meta_key=KEY-HERE

I thank you, but in my case all must be able to see all the custom fields of every users not only their own, how can I do? thanks

well, for that, you need to write custom endpoint.