diff --git a/tox.ini b/tox.ini
index 8277e9dd..e9d9b564 100644
--- a/tox.ini
+++ b/tox.ini
@@ -36,7 +36,7 @@ commands = python setup.py testr --coverage --testr-args='{posargs}'
 
 [testenv:debug]
 
-commands = oslo_debug_helper {posargs}
+commands = oslo_debug_helper -t keystonemiddleware/tests {posargs}
 
 [flake8]
 # D100: Missing docstring in public module