Keep Azure Powershell Cmdlts up to date with Portal Functionality
There are several things that you can do the in Management Portals that you are unable to do via powershell script. Such as setting Alerts, Backups for Websites, Automated Backups for SQL DB ,etc. These are crucial for anyone want to migrate a large set of DB's or websites over to Azure -- being able to automate these items instead of having to manually do in the portal.
MGC Mike commented
This is crucial. Right now if you run the following:
$URI = "https://management.core.windows.net/$subID/services/monitoring/alertrules"
$Rules = Invoke-RestMethod -Uri $URI -Method $method -Headers $headers -CertificateThumbprint $mgmtCertThumb -ErrorAction Stop
Write-Output $Rules | ConvertTo-Json
The JSON returned is different than that stated in the docs at https://msdn.microsoft.com/en-us/library/azure/dn510378.aspx
So the documentation is out of date from the cmdlets and REST API functionality, which is out of sync with the structure of the data on which they act.