WordPress at a glance
action is not described

user_new_form action-hook . WP 3.7.0

Fires at the end of the new user form.

Passes a contextual string to make both types of new user forms uniquely targetable. Contexts are 'add-existing-user' (Multisite), and 'add-new-user' (single site and network admin).

Usage

add_action( 'user_new_form', 'action_function_name_6949' );
function action_function_name_6949( $type ){
	// action...
}
$type(string)
A contextual string specifying which type of new user form the hook follows.

Where the hook is called

In file: /wp-admin/user-new.php
user_new_form
wp-admin/user-new.php 384
do_action( 'user_new_form', 'add-existing-user' );
wp-admin/user-new.php 511
do_action( 'user_new_form', 'add-new-user' );

Where the hook is used (in WP core)

Does not used.