diff --git a/script/tool/CHANGELOG.md b/script/tool/CHANGELOG.md
index a346ac093c..021259083a 100644
--- a/script/tool/CHANGELOG.md
+++ b/script/tool/CHANGELOG.md
@@ -1,5 +1,6 @@
-## NEXT
+## 13.1
 
+* Updates `version-check` to recognize Pigeon's platform test structure.
 * Pins `package:git` dependency to `2.0.x` until `dart >=2.18.0` becomes our
   oldest legacy.
 * Updates test mocks.
diff --git a/script/tool/lib/src/common/package_state_utils.dart b/script/tool/lib/src/common/package_state_utils.dart
index 5aabd75a4d..464dac6c18 100644
--- a/script/tool/lib/src/common/package_state_utils.dart
+++ b/script/tool/lib/src/common/package_state_utils.dart
@@ -110,7 +110,9 @@ bool _isTestChange(List<String> pathComponents) {
       pathComponents.contains('integration_test') ||
       pathComponents.contains('androidTest') ||
       pathComponents.contains('RunnerTests') ||
-      pathComponents.contains('RunnerUITests');
+      pathComponents.contains('RunnerUITests') ||
+      // Pigeon's custom platform tests.
+      pathComponents.first == 'platform_tests';
 }
 
 // True if the given file is an example file other than the one that will be
diff --git a/script/tool/pubspec.yaml b/script/tool/pubspec.yaml
index e450a1114e..2879ff1250 100644
--- a/script/tool/pubspec.yaml
+++ b/script/tool/pubspec.yaml
@@ -1,7 +1,7 @@
 name: flutter_plugin_tools
 description: Productivity utils for flutter/plugins and flutter/packages
 repository: https://github.com/flutter/plugins/tree/main/script/tool
-version: 0.13.0
+version: 0.13.1
 
 dependencies:
   args: ^2.1.0
diff --git a/script/tool/test/common/package_state_utils_test.dart b/script/tool/test/common/package_state_utils_test.dart
index c9ae5ba4c7..86029cdf73 100644
--- a/script/tool/test/common/package_state_utils_test.dart
+++ b/script/tool/test/common/package_state_utils_test.dart
@@ -80,6 +80,9 @@ void main() {
         'packages/a_plugin/example/macos/Runner.xcodeproj/project.pbxproj',
         'packages/a_plugin/example/windows/CMakeLists.txt',
         'packages/a_plugin/example/pubspec.yaml',
+        // Pigeon platform tests, which have an unusual structure.
+        'packages/a_plugin/platform_tests/shared_test_plugin_code/lib/integration_tests.dart',
+        'packages/a_plugin/platform_tests/test_plugin/windows/test_plugin.cpp',
       ];
 
       final PackageChangeState state = await checkPackageChangeState(package,