Is it possible to create an Agent Pool in TFS 2018 programatically, preferably via PowerShell? I cannot find anything like that in REST API.
I don't know why it's not well-documented, but this just worked for me against VSTS:
$token = 'myPAT'
$base64AuthInfo = [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes((":{0}" -f $token)))
$uri = 'https:///_apis/distributedtask/pools?api-version=4.1-preview.1'
$result = Invoke-RestMethod -Uri $uri -Method Post -ContentType "application/json" -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)} `
-Body (ConvertTo-Json @{name = 'foo'; autoProvision = $true})
I just looked at the REST API used in the web portal to create an agent pool and copied it; if the API version isn't the same in TFS 2018 as it is in VSTS, you can do the same thing to find the correct version to use.