diff --git a/scripts/diagnostics/Capture-MclCache.cmd b/scripts/diagnostics/Capture-MclCache.cmd
new file mode 100644
index 0000000..aab8990
--- /dev/null
+++ b/scripts/diagnostics/Capture-MclCache.cmd
@@ -0,0 +1,10 @@
+@echo off
+rem Double-click after a Media Creator Lite run finishes.
+rem Asks pro or ltsc, then runs Capture-MclCache.ps1 from this folder.
+setlocal
+set "LABEL=%~1"
+if "%LABEL%"=="" set /p "LABEL=Which MCL run just finished? Type pro or ltsc and press Enter: "
+if "%LABEL%"=="" set "LABEL=run"
+powershell.exe -NoProfile -ExecutionPolicy Bypass -File "%~dp0Capture-MclCache.ps1" -Label "%LABEL%"
+echo.
+pause
diff --git a/scripts/diagnostics/Capture-MclCache.ps1 b/scripts/diagnostics/Capture-MclCache.ps1
new file mode 100644
index 0000000..4a08ee0
--- /dev/null
+++ b/scripts/diagnostics/Capture-MclCache.ps1
@@ -0,0 +1,134 @@
+<#
+.SYNOPSIS
+    Captures the layout of a Media Creator Lite cache, plus its small
+    control files, so the PXE import can be checked against what the
+    current MCL actually writes.
+
+.DESCRIPTION
+    Run on the PC where Media Creator Lite just FINISHED a run. Run it once
+    after the Windows 11 Pro run and once after the Windows 11 LTSC run,
+    before starting the next MCL run (MCL deletes the cache when it starts).
+
+        .\Capture-MclCache.ps1 -Label pro
+        .\Capture-MclCache.ps1 -Label ltsc
+
+    It writes, under the Desktop:
+        mcl-capture-<label>-<timestamp>\
+            tree.csv      every file: path, size, last write time (UTC)
+            summary.txt   tag files and their contents, file counts, totals
+            files\        copies of the small text files (*.json, *.xml,
+                          *.tag, *.txt, *.ini, *.log, *.cmd, *.ps1, *.bat)
+                          under 5 MB, same relative paths
+        mcl-capture-<label>-<timestamp>.zip
+
+    Nothing large is copied: no WIM, driver, MSU or installer. Text copies
+    have any Azure SAS signature (sig=...) blanked, so the zip carries no
+    storage credential. Read-only on the cache; needs no admin rights.
+
+.PARAMETER Label
+    Short name for this run, for example pro or ltsc.
+
+.PARAMETER Root
+    The Media Creator folder. Default C:\ProgramData\GEAerospace\MediaCreator.
+
+.PARAMETER OutDir
+    Where to write the capture. Default: the current user's Desktop, or
+    this script's folder when there is no Desktop.
+#>
+param(
+    [Parameter(Mandatory = $true)][ValidatePattern('^[A-Za-z0-9_-]{1,20}$')][string]$Label,
+    [string]$Root = "C:\ProgramData\GEAerospace\MediaCreator",
+    [string]$OutDir = [Environment]::GetFolderPath("Desktop")
+)
+$ErrorActionPreference = "Stop"
+if (-not $OutDir) { $OutDir = $PSScriptRoot }   # no Desktop (e.g. run as SYSTEM)
+
+if (-not (Test-Path -LiteralPath $Root -PathType Container)) {
+    Write-Host "Media Creator folder not found: $Root" -ForegroundColor Red
+    exit 1
+}
+$Root = (Resolve-Path -LiteralPath $Root).ProviderPath.TrimEnd('\')
+
+$stamp = Get-Date -Format "yyyyMMdd-HHmmss"
+$dest = Join-Path $OutDir "mcl-capture-$Label-$stamp"
+$filesDir = Join-Path $dest "files"
+New-Item -ItemType Directory -Path $filesDir -Force | Out-Null
+
+$textExt = @(".json", ".xml", ".tag", ".txt", ".ini", ".log", ".cmd", ".ps1", ".bat")
+$maxCopy = 5MB
+# Azure SAS signature in a URL or connection string.
+$sasPattern = '(?i)(sig=)[^&"''\s<]+'
+
+Write-Host "Reading $Root ..."
+$all = @(Get-ChildItem -LiteralPath $Root -Recurse -Force -File -ErrorAction SilentlyContinue)
+
+$rows = foreach ($f in $all) {
+    [pscustomobject]@{
+        Path          = $f.FullName.Substring($Root.Length + 1)
+        Length        = $f.Length
+        LastWriteUtc  = $f.LastWriteTimeUtc.ToString("yyyy-MM-ddTHH:mm:ssZ")
+    }
+}
+$rows | Sort-Object Path | Export-Csv -LiteralPath (Join-Path $dest "tree.csv") -NoTypeInformation -Encoding UTF8
+
+$copied = 0
+$redacted = 0
+$skippedBig = New-Object System.Collections.Generic.List[string]
+foreach ($f in $all) {
+    if ($textExt -notcontains $f.Extension.ToLower()) { continue }
+    $rel = $f.FullName.Substring($Root.Length + 1)
+    if ($f.Length -gt $maxCopy) { $skippedBig.Add("$rel ($($f.Length) bytes)"); continue }
+    $target = Join-Path $filesDir $rel
+    New-Item -ItemType Directory -Path (Split-Path $target -Parent) -Force | Out-Null
+    $bytes = [System.IO.File]::ReadAllBytes($f.FullName)
+    $text = [System.Text.Encoding]::UTF8.GetString($bytes)
+    if ($text -match $sasPattern) {
+        $text = [regex]::Replace($text, $sasPattern, '${1}REDACTED')
+        $bytes = [System.Text.Encoding]::UTF8.GetBytes($text)
+        $redacted++
+    }
+    [System.IO.File]::WriteAllBytes($target, $bytes)
+    $copied++
+}
+
+$tags = @($all | Where-Object { $_.Extension -eq ".tag" })
+$sum = New-Object System.Collections.Generic.List[string]
+$sum.Add("Media Creator Lite cache capture")
+$sum.Add("Label:     $Label")
+$sum.Add("Captured:  $(Get-Date -Format 'yyyy-MM-dd HH:mm:ss zzz')")
+$sum.Add("Computer:  $env:COMPUTERNAME")
+$sum.Add("Root:      $Root")
+$sum.Add("PowerShell $($PSVersionTable.PSVersion)")
+$sum.Add("")
+$sum.Add("Files: $($all.Count), total $([math]::Round((($all | Measure-Object Length -Sum).Sum) / 1GB, 2)) GB")
+$sum.Add("Text files copied: $copied (SAS signatures blanked in $redacted)")
+$sum.Add("")
+$sum.Add("Tag files ($($tags.Count)):")
+foreach ($t in $tags) {
+    $content = (Get-Content -LiteralPath $t.FullName -Raw -ErrorAction SilentlyContinue)
+    if ($content) { $content = $content.Trim() }
+    $sum.Add("  $($t.FullName.Substring($Root.Length + 1))  [$content]  written $($t.LastWriteTime)")
+}
+if ($tags.Count -eq 0) { $sum.Add("  NONE - the MCL run did not finish") }
+$sum.Add("")
+$sum.Add("Top-level folders:")
+foreach ($g in ($rows | Group-Object { ($_.Path -split '\\')[0..1] -join '\' } | Sort-Object Name)) {
+    $gb = [math]::Round((($g.Group | Measure-Object Length -Sum).Sum) / 1GB, 2)
+    $sum.Add("  $($g.Name): $($g.Count) files, $gb GB")
+}
+if ($skippedBig.Count) {
+    $sum.Add("")
+    $sum.Add("Text files over 5 MB, not copied:")
+    foreach ($s in $skippedBig) { $sum.Add("  $s") }
+}
+$sum | Set-Content -LiteralPath (Join-Path $dest "summary.txt") -Encoding UTF8
+
+$zip = "$dest.zip"
+Compress-Archive -Path (Join-Path $dest "*") -DestinationPath $zip -Force
+
+Write-Host ""
+Write-Host "Captured $($all.Count) files ($copied text files copied)." -ForegroundColor Green
+if ($tags.Count -eq 0) {
+    Write-Host "WARNING: no .tag file. MCL did not finish this run." -ForegroundColor Yellow
+}
+Write-Host "Send back: $zip"