Action return being "converted" to object

Hi

I have a workflow with a few action in it. One of the actions returns and array of strings (link of vmnics). Then in a later scriptable task I am trying to add these vmnics to a vswitch.

In the below snippet NetworkData is my Array of String

var switchSpec = new VcHostVirtualSwitchSpec();
var loabBalPolicy = "loadbalance_srcid"
switchSpec.numPorts = 1024;
switchSpec.mtu = mtu;
switchSpec.bridge = new VcHostVirtualSwitchBondBridge();
switchSpec.bridge.nicDevice = NetworkData;

When I run the workflow I get the below error

Unable to set property 'nicDevice' on object VcHostVirtualSwitchBondBridge : org.mozilla.javascript.NativeString

nicDevice is meant to be an array of string? Do I have to iterate through NetworkData and re-create my array ?

If I output typeof(NetworkData) is state the type as object.