Returning feature class from Python toolbox

I am trying to return a feature class (my sample data is a polygon fc) from a Python toolbox and cannot find any information about what I have to set to get it to work. This runs successfully and gives me a record count of 917 but in ArcCatalog in the results window out: <empty> (and the icon looks like a table not a polygon feature class).

import arcpy



class Toolbox(object):
    def __init__(self):
        self.label='BasicOutput'
        self.alias='BasicOutput'
        self.description='BasicOutput'
        self.summary=self.description

        # List of tool classes associated with this toolbox
        self.tools=[BasicOutput]


class BasicOutput(object):
    def __init__(self):
        """Define the tool (tool name is the name of the class)."""
        self.label='BasicOutput'
        self.description='BasicOutput'
        self.summary=self.description


    def getParameterInfo(self):
        ps=[
            arcpy.Parameter(
                displayName='out',
                name='out',
                datatype='GPFeatureRecordSetLayer',
                parameterType='Derived',
                direction='Output'),
            ]
        return ps


    def updateParameters(self,parameters): return
    def updateMessages(self,parameters): return


    def execute(self,parameters,messages):
        fs=arcpy.FeatureSet()
        fs.load(r'D:\customApps\PaddockGRASP\BasicOutput.gdb/Cadastre')
        arcpy.AddMessage('record count: %s'%arcpy.GetCount_management(fs))
        parameters[0].value=fs

I will then be publishing it as a GP service in ArcGis server, but can't even get it working in ArcCatalog! Using ArcGis 10.2.1.