by Björn Fisseler.
Gabriel,
I logged into our Moodle using the user account that I set up for the webservices. Than I simply accepted the site policy that showed up.
You can find the settings for the site policy here: Administration > Security > Website rights (don't know if that is the correct breadcrumb, 'cause I just translated it; but you can also search for "sitepolicy" within your Moodle).
Btw. I suggest that you really login using the webservice user account and try for yourself if everything works as expected.
Regards