diff --git a/tests/conftest.py b/tests/conftest.py
index c9df477..3e487f8 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -14,5 +14,5 @@
         ),
     ]
 )
-def anyio_backend(request) -> tuple[str, dict[str, Any]]:
+def anyio_backend(request: pytest.FixtureRequest) -> tuple[str, dict[str, Any]]:
     return request.param