I am using the API V2 PHP SDK.  I have made successful queries but can't find any formal documentation on the API, only tutorials and examples that do not explore many of the parameters of the various methods.  The source code also lacks any comments about the parameters.

For instance the ZCRMModule class has a method getRecords:

public function getRecords($cvId=null, $sortByField=null, $sortOrder=null, $startIndex=1,$endIndex=200,$headers=null)

but I can't find any explanation of the parameters, except by trying to understand the (uncommented) code.  The examples in the tutorials do not use any parameters.

Any pointers appreciated.