Create Container with Parent in Powershell

I can't seem to get a script of mine working, can someone help me figure this out?  I'm still pretty new to using the API and I maybe touch PowerShell twice a year, so this is kinda new territory for me.  Whenever I try to run it, it asks me for the EntityName, so I already know it doesn't work like it does in my head.

Here's the script:

param(

[string]$parentID,

[string]$name,

[int]$statCalc)

#Credentials should be passed from outside in a variable called $cred.

# Connect to SWIS

$hostname = "localhost"

$swis = Connect-Swis -Credential $cred -host $hostname

# Define Properties

$newContainerProps = @{

    parentID = $parentID;

    Name = $name;

statusCalculator = $statCalc;

    # === default values ===

    frequency = 60;

    owner = 'CORE'

    Description = 'Active-Passive Pair of Service Monitors'

    pollingEnabled = 'TRUE'

}

#Create the Container

Invoke-SwisVerb $swis -Verb createContainerWithParent -Arguments $newContainerProps