Punctuation
diff --git a/tool/grind.dart b/tool/grind.dart
index 27b6dd7..799a6a8 100644
--- a/tool/grind.dart
+++ b/tool/grind.dart
@@ -196,7 +196,7 @@
       'artifacts/*.js gs://compilation_artifacts/$version/');
 }
 
-@Task('Delete, re-download, and reinitialize the Flutter submodule')
+@Task('Delete, re-download, and reinitialize the Flutter submodule.')
 void setupFlutterSubmodule() {
   final flutterDir = Directory('flutter');