You need to look to solve the problem of NO WFA Provided commands in the following order:
1. Look for a Posh cmdlet and create your own WFA commands using those. This will almost certianly solve your problem. Powershell cmdlets for almost everything that is possible to do with a cluster/array is provided. See the documentation on this at WFA->Help->Support Links -> Powershell cmdlets Help.
See my code example provided here for the specific case of creating a security login account: WFA Input Type of 'password' issues
2. If at all there is no Powershell cmdlet available for a task, you can create WFA commands using SDK and ZAPIs. They are bundled for Posh and Perl languages.
3. Invoking direct InvokeWfaCluster-CLI is okay but not what I would recommend to use. Not that this will not work, or will create any unwanted issues. It will be fine mostly excapt it may end up askign for User-Inputs. Also the command output unlike ZAPI or Posh cmdlets is returned in string format and those are compatively difficult to parse and loop through or be useful in creating advanced level commands. One liners its fine. You'll start to face this as you develope more commands.
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