diff --git a/tox.ini b/tox.ini
index 0dacf9f2..c50df0eb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -57,6 +57,8 @@ commands =
   sphinx-build -j auto -W -T --keep-going {posargs} docs/ docs/_build/html
 passenv =
   CI
+  GITHUB_BASE_REF
+  GITHUB_REF_NAME
 
 [testenv:docs-clean]
 skip_install = true