To use the PHP API, you must include keyworddesk-customer-api.php After that you can create an instance of KeyworddeskApi
$keyworddeskApi = new KeyworddeskApi($username,$password);
If you have an instance just do this:
$keyword = $keyworddeskApi->getKeywordData(array('hund'),array('suggestedBid','googleInTitleCount','googleResultCount','searchVolume'));