Windows Monitor - Restart Required Script

<#
This resource is provided as a convenience for Level users. We cannot 
guarantee it will work in all environments. Please test before deploying 
to your production environment. We welcome contributions to our community 
library

Level Library
https://level.io/library/script-windows-monitor-restart-required
#>

function Get-PendingRebootStatus {

    $rebootRequired = $false

    # 1. Windows Update Agent (best signal)
    try {
        $sysInfo = New-Object -ComObject "Microsoft.Update.SystemInfo"
        if ($sysInfo.RebootRequired) {
            return $true
        }
    } catch {
        # COM not available; continue with others
    }

    # 2. Component Based Servicing
    if (Test-Path 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Component Based Servicing\RebootPending') {
        return $true
    }

    # 3. Windows Update's own reboot-required flag
    if (Test-Path 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\RebootRequired') {
        return $true
    }

    # 4. Pending file operations (drivers, installers, AV)
    try {
        $pendingOps = (Get-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager' -ErrorAction SilentlyContinue).PendingFileRenameOperations
        if ($pendingOps) {
            return $true
        }
    } catch {}

    # 5. Computer rename pending
    try {
        $active = (Get-ItemProperty 'HKLM:\SYSTEM\CurrentControlSet\Control\ComputerName\ActiveComputerName').ComputerName
        $pending = (Get-ItemProperty 'HKLM:\SYSTEM\CurrentControlSet\Control\ComputerName\ComputerName').ComputerName
        if ($active -ne $pending) {
            return $true
        }
    } catch {}

    return $rebootRequired
}

if (Get-PendingRebootStatus) {
    Write-Output "ALERT: Reboot Required"
} else {
    Write-Output "No reboot is required."
}