For vSphere tagging, most PowerCLI users go for the “Get-Tag”,”Get-TagCategory”, or “Get-TagAssignment” methods.
Depending on the size of your vCenter, inventory count, but more importantly, Tag count, the CisService methods may provide better performance for vSphere Tagging.

To access these APIs, you will need to log in to vcenter with the following string.  (Adjust vcenter/user/pass as needed)
connect-cisserver “vcenter.pcli.me” -username “administrator@vsphere.local” -pass “mypassword”

To start, each method has documentation.  I will say, it’s not extremely easy to read, but its better than leaving us stranded.
I will show you how to pull the command documentation for Tag Categories and you should be able to translate this for other methods.
Pasting the following two lines will show you the “Operations” you can complete within the “tagging.category.”
$allCateMethod = Get-CisService com.vmware.cis.tagging.category
$allCateMethod.Help

From here, you can expand the help.  Lets say you want to create a new Tag Category.  You add on “create” to the help command and it will show you what you need to complete the command.
$allCateMethod.Help.create
$allCateMethod.Help.create.create_spec

Below, I will post the most common methods I use.

# Create a new Tagging Category: (I included all possible options for the specs after the comment hash)
$allCateMethod = Get-CisService com.vmware.cis.tagging.category
$spec = $allCateMethod.Help.create.create_spec
$spec.name = “myFirstCategory”
$spec.description = “”
$spec.cardinality = “MULTIPLE” # “SINGLE” # yes it needs to be all caps….
$spec.associable_types = “virtualmachine”,”vmhost” # Cluster, Datacenter, Datastore, DatastoreCluster, DistributedPortGroup, DistributedSwitch, Folder, ResourcePool, VApp, VirtualPortGroup
$allCateMethod.Create($spec)

# Get all Tag Categories:
$allCateMethod = Get-CisService com.vmware.cis.tagging.category
$allcate = $allcateMethod.list()
$cates = @()
foreach ($cate in $allcate) {
$cates += $allCateMethod.Get($cate)
}
$cates

# Create a new Tag:  (a Tag needs a category so be sure to create one first)
$alltagMethod = Get-CisService com.vmware.cis.tagging.tag
$spec = $alltagMethod.Help.create.create_spec
$spec.name = “myFirstTag”
$spec.description = “”
$spec.category_id = $cates | where {$_.name -eq “myFirstCategory”} | %{$_.id.value}
$alltagMethod.Create($spec)

# Get all Tags:
$alltagMethod = Get-CisService com.vmware.cis.tagging.tag
$alltag = $alltagMethod.list()
$tags = @()
foreach ($tag in $alltag) {
$tags += $alltagMethod.Get($tag)
}
$tags

# From here, you can now Attach, Detach, or Query tags to objects.   To access those objects (like a Virtual Machine) you will need to connect to vcenter with our VIServer connection.
connect-viserver “vcenter.pcli.me” -username “administrator@vsphere.local” -pass “mypassword”

Now we can pull in object IDs and match them with Tag IDs.
# Attach a Tag to a VirtualMachine:
$mytag = $tags | where {$_.name -eq “myFirstTag”}
$vm = Get-VM -Name “myFirstVM”
$tagAssign = Get-CisService -Name com.vmware.cis.tagging.tag_association
$spec = $tagAssign.Help.attach.object_id.Create()
$spec.type = $vm.ExtensionData.MoRef.Type
$spec.id = $vm.ExtensionData.MoRef.Value
$tagAssign.attach($mytag.id.Value, $spec)

# Then to check the Association:
$tagAsso = Get-CisService -Name com.vmware.cis.tagging.tag_association
$tagAsso.list_attached_objects($mytag.id.value)

If you dig deep into the documentation of these methods, you will find ways to Add, Delete, Create, and even Batch assign tags.  I gave you the starting point here.

One extra for the road:
# Quick method to delete a Tag Category:   (Quick note…. Deleting a category WILL delete all of the tags under it and the API call will not prompt you about it.)
$mycateID = $cates |where {$_.name -eq “myFirstCategory”} |%{$_.id.value}
$allCateMethod = Get-CisService com.vmware.cis.tagging.category
$allcateMethod.Delete($mycateID)

Let me know if you have any questions @vmnick0 on twitter.

Here is a quick line of code you can throw in to your existing scripts if you want to do some validation based on the type of vcenter.
As more companies are moving to the vCenter appliance, MS Windows issues go away.   Until that time, it’s good to alert on disk space and CPU usage for the Windows vCenter.

The quick one-liner to check the vCenter OS:
if(($global:DefaultVIServer | %{$_.extensiondata.content.about.ostype}) -match “win”){ $windows}else{$Linux}

Here is a Windows vCenter “CPU and Disk space” check script:

$vcenter = “vcenter.pcli.me”
$localWindowsAccountUser = “user001”
$localWindowsAccountPass = “test”
## if you want to use a domain account then edit the “$pcstring” var below

Connect-VIServer $vcenter

if(($global:DefaultVIServer | %{$_.extensiondata.content.about.ostype}) -match “win”){
$report=@()
$pcstring = $vcenter+”\”+$localWindowsAccountUser
$Credential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $pcstring,(ConvertTo-SecureString -String $localWindowsAccountPass -AsPlainText -Force)
$temp = get-WmiObject win32_logicaldisk -Computername $vcenter -credential $Credential
foreach($b in ($temp | where {$_.drivetype -eq “3”})){
$reportrow = “” | select VMname, DriveLetter, VolumeName,CapacityGB, FreespaceGB,percentFree
$reportrow.vmname = $vcenter
$reportrow.driveletter = $b.DeviceID
$reportrow.VolumeName = $b.VolumeName
$reportrow.capacityGB = “{0:N3}” -f ($b.Size / 1073741824)
$reportrow.freespaceGB = “{0:N3}” -f ($b.FreeSpace / 1073741824)
$reportrow.percentfree = [System.Math]::floor(($b.FreeSpace / $b.Size)*100)
$report += $reportrow
}
$cpucheck = get-WmiObject win32_processor  -Computername $vcenter -credential $Credential | Measure-Object -property LoadPercentage -Average | Select Average
if(([int]($cpucheck.average)) -ge 90){
$smtpServer = “smtp.pcli.me”
$msg = new-object Net.Mail.MailMessage
$smtp = new-object Net.Mail.SmtpClient($smtpServer)
$msg.From = “Script@pcli.me”
$msg.To.Add(“Team@pcli.me”)
$sub = “vCenter HIGH CPU usage found for “+$vcenter
$msg.subject = $sub
$msg.Body = “”
$smtp.Send($msg)
}}
Disconnect-VIServer -Server $global:DefaultVIServers -Force -confirm:$False

#The following is a good starting template if you have a software suite that uses web based rest APIs.
#** Note,  using Powershell version 4 is highly recommended if the API requires HTTPS and/or uses Self Signed Certs.
# Be sure to edit the user,password and URL below.

# This single line helps get around Cert issues that can prevent you from connecting to the server.  Only use this line if you have connectivity or SSL issues.
[System.Net.ServicePointManager]::ServerCertificateValidationCallback = { $true }

#The Vars and code:
$User = “testUsername”
$PWord = ConvertTo-SecureString –String “testPassword” –AsPlainText -Force
$Cred = New-Object –TypeName System.Management.Automation.PSCredential –ArgumentList $User, $PWord

$wc = New-Object System.Net.WebClient
$wc.Headers.Add(“Authorization”, “Basic $( [System.Convert]::ToBase64String([System.Text.Encoding]::UTF8.GetBytes(“$($Cred.UserName.TrimStart(‘\’)):$($Cred.GetNetworkCredential().Password)”)) )”)
$temp = $wc.DownloadString(“https://TheApiServer.com/api/”)
$temp

#From here you can use the $temp var to dig further into the API and then format what output you want.   You can review one of my older posts if you need help creating a report for easy exporting. If the API posts back something usable you can just use one of the many powershell Export- functions.