You can use Get-NaHelp or Get-NcHelp to see which APIs are used:
PS C:\> Get-NaHelp -Category aggr | select name, api | ft -AutoSize
Name Api
---- ---
Add-NaAggr {aggr-add}
Confirm-NaAggrSpareLow {aggr-check-spare-low}
Get-NaAggr {aggr-list-info}
Get-NaAggrFilerInfo {aggr-get-filer-info}
Get-NaAggrMediaScrub {aggr-mediascrub-list-info}
Get-NaAggrOption {aggr-options-list-info}
Get-NaAggrScrub {aggr-scrub-list-info}
Get-NaAggrSpace {aggr-space-list-info}
Get-NaAggrVerify {aggr-verify-list-info}
New-NaAggr {aggr-create}
New-NaAggrMirror {aggr-mirror}
Remove-NaAggr {aggr-destroy}
Rename-NaAggr {aggr-rename}
Resume-NaAggrScrub {aggr-scrub-resume}
Resume-NaAggrVerify {aggr-verify-resume}
Set-NaAggr {aggr-online, aggr-offline, aggr-restrict}
Set-NaAggrOption {aggr-set-option}
Set-NaAggrRaidType {aggr-modify-raid-type}
Split-NaAggrMirror {aggr-split}
Start-NaAggrScrub {aggr-scrub-start}
Start-NaAggrVerify {aggr-verify-start}
Stop-NaAggrScrub {aggr-scrub-stop}
Stop-NaAggrVerify {aggr-verify-stop}
Suspend-NaAggrScrub {aggr-scrub-suspend}
Suspend-NaAggrVerify {aggr-verify-suspend}