API function server_get_php_versions missing system php

The system PHP version (Server PHP Settings) is missing in Output of this function.
It only contains the rows of table "server_php". On the other hand the dropdown of the PHP version in the website GUI contains the system PHP as selectable option as well.

 

How can I get all possible versions by API or at least additionally the default version?

 

for the default something like

Code:

$server = $remote->server_get($session_id, $server_id, $section ='');
$php_version = str_replace('php', '', explode('-', $server['web']['php_fpm_init_script'])[0]);

installed versions

Code:

$installed_versions = $remote->server_get_php_versions($session_id, $server_id, 'php-fpm');

 

Working fine, thx