diff --git a/ament_index_python/ament_index_python/cli.py b/ament_index_python/ament_index_python/cli.py
index 4fa8f67..775eeea 100644
--- a/ament_index_python/ament_index_python/cli.py
+++ b/ament_index_python/ament_index_python/cli.py
@@ -27,11 +27,11 @@ def main(argv: List[str] = sys.argv[1:]) -> Optional[str]:
     arg = parser.add_argument(
         'resource_type', nargs='?', metavar='TYPE',
         help='The type of the resource')
-    arg.completer = resource_type_completer
+    arg.completer = resource_type_completer  # type: ignore[attr-defined]
     arg = parser.add_argument(
         'resource_name', nargs='?', metavar='NAME',
         help='The name of the resource')
-    arg.completer = resource_name_completer
+    arg.completer = resource_name_completer  # type: ignore[attr-defined]
 
     try:
         from argcomplete import autocomplete
diff --git a/ament_index_python/package.xml b/ament_index_python/package.xml
index bc15f95..dc2646e 100644
--- a/ament_index_python/package.xml
+++ b/ament_index_python/package.xml
@@ -18,6 +18,7 @@
   <test_depend>ament_copyright</test_depend>
   <test_depend>ament_flake8</test_depend>
   <test_depend>ament_pep257</test_depend>
+  <test_depend>ament_mypy</test_depend>
   <test_depend>python3-pytest</test_depend>
 
   <export>
diff --git a/ament_index_python/py.typed b/ament_index_python/py.typed
new file mode 100644
index 0000000..e69de29
diff --git a/ament_index_python/test/test_mypy.py b/ament_index_python/test/test_mypy.py
new file mode 100644
index 0000000..e4f0247
--- /dev/null
+++ b/ament_index_python/test/test_mypy.py
@@ -0,0 +1,20 @@
+# Copyright 2024 Open Source Robotics Foundation, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ament_mypy.main import main
+
+
+def test_mypy() -> None:
+    rc = main(argv=['--exclude', 'test'])
+    assert rc == 0, 'Found code style errors / warnings'
\ No newline at end of file