diff --git a/eng/scripts/ChangedFiles-Functions.ps1 b/eng/scripts/ChangedFiles-Functions.ps1
index 0968b252df54..a2c9202db867 100644
--- a/eng/scripts/ChangedFiles-Functions.ps1
+++ b/eng/scripts/ChangedFiles-Functions.ps1
@@ -18,8 +18,8 @@ function Get-ChangedFiles($baseCommitish = "HEAD^", $targetCommitish = "HEAD", $
   return $changedFiles
 }
 
-function Get-ChangedSwaggerFiles() {
-  $changedFiles = Get-ChangedFilesUnderSpecification
+function Get-ChangedSwaggerFiles($changedFiles = (Get-ChangedFiles)) {
+  $changedFiles = Get-ChangedFilesUnderSpecification($changedFiles)
 
   $changedSwaggerFiles = $changedFiles.Where({ 
     $_.EndsWith(".json")
diff --git a/eng/scripts/TypeSpec-Requirement.ps1 b/eng/scripts/TypeSpec-Requirement.ps1
index ee4855316a8b..e7909dc10026 100644
--- a/eng/scripts/TypeSpec-Requirement.ps1
+++ b/eng/scripts/TypeSpec-Requirement.ps1
@@ -1,5 +1,10 @@
 [CmdletBinding()]
 param (
+  [Parameter(Position = 0)]
+  [string] $BaseCommitish = "HEAD^",
+  [Parameter(Position = 1)]
+  [string] $TargetCommitish = "HEAD"
+
 )
 Set-StrictMode -Version 3
 
@@ -9,7 +14,7 @@ Set-StrictMode -Version 3
 $repoPath = Resolve-Path "$PSScriptRoot/../.."
 $pathsWithErrors = @()
 
-$filesToCheck = @(Get-ChangedSwaggerFiles).Where({
+$filesToCheck = (Get-ChangedSwaggerFiles (Get-ChangedFiles $BaseCommitish $TargetCommitish)).Where({
   ($_ -notmatch "/(examples|scenarios|restler|common|common-types)/") -and
   ($_ -match "specification/[^/]+/(data-plane|resource-manager).*?/(preview|stable)/[^/]+/[^/]+\.json$")
 })
@@ -30,15 +35,21 @@ else {
   foreach ($file in $filesToCheck) {
     LogInfo "Checking $file"
 
-    $jsonContent = Get-Content (Join-Path $repoPath $file) | ConvertFrom-Json -AsHashtable
+    try {
+      $jsonContent = Get-Content (Join-Path $repoPath $file) | ConvertFrom-Json -AsHashtable
 
-    if ($null -ne ${jsonContent}?["info"]?["x-typespec-generated"]) {
-      LogInfo "  OpenAPI was generated from TypeSpec (contains '/info/x-typespec-generated')"
-      # Skip further checks, since spec is already using TypeSpec
-      continue
+      if ($null -ne ${jsonContent}?["info"]?["x-typespec-generated"]) {
+        LogInfo "  OpenAPI was generated from TypeSpec (contains '/info/x-typespec-generated')"
+        # Skip further checks, since spec is already using TypeSpec
+        continue
+      }
+      else {
+        LogInfo "  OpenAPI was not generated from TypeSpec (missing '/info/x-typespec-generated')"
+      }
     }
-    else {
-      LogInfo "  OpenAPI was not generated from TypeSpec (missing '/info/x-typespec-generated')"
+    catch {
+      LogWarning "  OpenAPI cannot be parsed as JSON, so assuming not generated from TypeSpec"
+      LogWarning "    $_"
     }
 
     # Extract path between "specification/" and "/(preview|stable)"