diff --git a/tools/propose_projects_yaml_update.sh b/tools/propose_projects_yaml_update.sh
index b0ea381d95..a369e77b9e 100755
--- a/tools/propose_projects_yaml_update.sh
+++ b/tools/propose_projects_yaml_update.sh
@@ -52,7 +52,7 @@ else
 fi
 
 git review -s
-python tools/normalize_projects_yaml.py
+tox -e normalize-projects-yaml
 
 if ! git diff --stat --exit-code HEAD ; then
     # Commit and review
diff --git a/tox.ini b/tox.ini
index 4e5cfb213d..ecedcd27c4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -133,3 +133,9 @@ deps =
 commands =
   python tools/add-projects-to-main.py
   git diff-files --quiet
+
+[testenv:normalize-projects-yaml]
+deps =
+  ruamel.yaml
+commands =
+  {toxinidir}/tools/normalize_projects_yaml.py