Run an external program
In the Execute external program ("ScriptOptions") section, you can specify that a program (script) is executed after creating the new user.
"ScriptOptions" : {
"IsHiddenFromRequester": false,
"IsScriptEnabledDefault": true,
"DisplayName": "Create a welcome package",
"Path": "\\\\srv-8man\\scripts\\WelcomePackage.ps1",
"CommandLineParameters": "{CommonName} {samaccountname} {DomainName}"
},