This article explains how to download the SQL Clone Agent service silently over the network.

You can use the following PowerShell commands, configured as necessary to achieve this:

$username = "<username that can access SQL Clone Server>"
$plaintextPassword = "<password for that user>"
$agentInstaller = "<some path>\SQLCloneSingleUserInstaller.exe"
$password = ConvertTo-SecureString $plaintextPassword -AsPlainText -Force
$credentials = New-Object System.Management.Automation.PSCredential ($username, $password)
Invoke-WebRequest -Uri "http://<server machine>:14145/download/agentinstaller" -OutFile $agentInstaller -Credential $credentials

To check $process.ExitCode to see if it was successful run:

$process = Start-Process -FilePath "$AgentInstaller" -ArgumentList ("-s", "SERVICEUSERNAME=$Username", "SERVICEPASSWORD=$Password") -Wait -PassThru

Related article: Installing an Agent to create an Image