diff --git a/ui_automator/ui_automator.py b/ui_automator/ui_automator.py
index aacd2df..550b94b 100644
--- a/ui_automator/ui_automator.py
+++ b/ui_automator/ui_automator.py
@@ -26,7 +26,7 @@
 import os
 import re
 import time
-from typing import Any
+from typing import Any, Sequence
 import unittest
 
 from absl import app
@@ -568,8 +568,8 @@
         print(f.read())
 
 
-# TODO(google-home-testsuite-dev+ui-automator): Type of argv should be Sequence[str].
-def _main(argv) -> None:
+def _main(argv: Sequence[str]) -> None:
+  """Main function to run the UI Automator."""
   if argv and len(argv) > 1:
     raise app.UsageError(f'Too many command-line arguments: {argv!r}')