diff --git a/main.py b/main.py
index 05d5537..e059e06 100644
--- a/main.py
+++ b/main.py
@@ -23,13 +23,19 @@
 
 def main() -> int:
     parser = argparse.ArgumentParser(description="Run the browser agent with a query.")
-    parser.add_argument(
+    query_group = parser.add_mutually_exclusive_group(required=True)
+    query_group.add_argument(
         "--query",
         type=str,
-        required=True,
         help="The query for the browser agent to execute.",
     )
-
+    query_group.add_argument(
+        "--query_file",
+        type=argparse.FileType("r", encoding="utf-8"),
+        help=(
+            "Path to a file containing the query for the browser agent to execute."
+        ),
+    )
     parser.add_argument(
         "--env",
         type=str,
@@ -56,6 +62,18 @@ def main() -> int:
     )
     args = parser.parse_args()
 
+    if args.query_file:
+        with args.query_file as f:
+            filename = f.name
+            query = f.read()
+        if not query.strip():
+            raise ValueError(
+                f"Query file '{filename}' is empty or contains only whitespace."
+            )
+    else:
+        # This branch is taken if --query is used.
+        query = args.query
+
     if args.env == "playwright":
         env = PlaywrightComputer(
             screen_size=PLAYWRIGHT_SCREEN_SIZE,
@@ -73,7 +91,7 @@ def main() -> int:
     with env as browser_computer:
         agent = BrowserAgent(
             browser_computer=browser_computer,
-            query=args.query,
+            query=query,
             model_name=args.model,
         )
         agent.agent_loop()
diff --git a/test_main.py b/test_main.py
index 4bee9ff..bf38890 100644
--- a/test_main.py
+++ b/test_main.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 
 import unittest
-from unittest.mock import patch, MagicMock
+from unittest.mock import patch, MagicMock, mock_open
 import main
 
 class TestMain(unittest.TestCase):
@@ -27,6 +27,7 @@ def test_main_playwright(self, mock_browser_agent, mock_playwright_computer, moc
         mock_args.initial_url = 'test_url'
         mock_args.highlight_mouse = True
         mock_args.query = 'test_query'
+        mock_args.query_file = None
         mock_args.model = 'test_model'
         mock_args.api_server = None
         mock_args.api_server_key = None
@@ -39,7 +40,11 @@ def test_main_playwright(self, mock_browser_agent, mock_playwright_computer, moc
             initial_url='test_url',
             highlight_mouse=True
         )
-        mock_browser_agent.assert_called_once()
+        mock_browser_agent.assert_called_once_with(
+            browser_computer=mock_playwright_computer.return_value.__enter__.return_value,
+            query='test_query',
+            model_name='test_model',
+        )
         mock_browser_agent.return_value.agent_loop.assert_called_once()
 
     @patch('main.argparse.ArgumentParser')
@@ -49,6 +54,7 @@ def test_main_browserbase(self, mock_browser_agent, mock_browserbase_computer, m
         mock_args = MagicMock()
         mock_args.env = 'browserbase'
         mock_args.query = 'test_query'
+        mock_args.query_file = None
         mock_args.model = 'test_model'
         mock_args.api_server = None
         mock_args.api_server_key = None
@@ -62,8 +68,61 @@ def test_main_browserbase(self, mock_browser_agent, mock_browserbase_computer, m
             screen_size=main.PLAYWRIGHT_SCREEN_SIZE,
             initial_url='test_url'
         )
-        mock_browser_agent.assert_called_once()
+        mock_browser_agent.assert_called_once_with(
+            browser_computer=mock_browserbase_computer.return_value.__enter__.return_value,
+            query='test_query',
+            model_name='test_model',
+        )
         mock_browser_agent.return_value.agent_loop.assert_called_once()
 
+    @patch('main.argparse.ArgumentParser')
+    @patch('main.PlaywrightComputer')
+    @patch('main.BrowserAgent')
+    def test_main_with_query_file(self, mock_browser_agent, mock_playwright_computer, mock_arg_parser):
+        mock_args = MagicMock()
+        mock_args.env = 'playwright'
+        mock_args.initial_url = 'test_url'
+        mock_args.highlight_mouse = False
+        mock_args.query = None
+        # mock_open is used to simulate opening a file
+        m = mock_open(read_data='query from file')
+        # The file object needs a 'name' attribute for the error message
+        m.return_value.name = 'test_query.txt'
+        mock_args.query_file = m()
+        mock_args.model = 'test_model'
+        mock_args.api_server = None
+        mock_args.api_server_key = None
+        mock_arg_parser.return_value.parse_args.return_value = mock_args
+
+        main.main()
+
+        mock_playwright_computer.assert_called_once_with(
+            screen_size=main.PLAYWRIGHT_SCREEN_SIZE,
+            initial_url='test_url',
+            highlight_mouse=False
+        )
+        mock_browser_agent.assert_called_once_with(
+            browser_computer=mock_playwright_computer.return_value.__enter__.return_value,
+            query='query from file',
+            model_name='test_model',
+        )
+        mock_browser_agent.return_value.agent_loop.assert_called_once()
+
+    @patch('main.argparse.ArgumentParser')
+    def test_main_with_empty_query_file(self, mock_arg_parser):
+        mock_args = MagicMock()
+        mock_args.query = None
+        # Simulate an empty file
+        m = mock_open(read_data='  ')
+        m.return_value.name = 'empty.txt'
+        mock_args.query_file = m()
+        mock_arg_parser.return_value.parse_args.return_value = mock_args
+
+        with self.assertRaisesRegex(
+            ValueError, "Query file 'empty.txt' is empty or contains only whitespace."
+        ):
+            main.main()
+
+
 if __name__ == '__main__':
     unittest.main()