So this seems to work, but the call to set token seems a bit clunky.

$service = Keyring_Service_Facebook::init();

echo $service->is_connected() ? ‘true’ : ‘false’;

$token = current($service->get_tokens());

$service->set_token( $token );

$res = $service->request(‘https://graph.facebook.com/me?fields=id,name’);

print_r($res);