diff --git a/tox.ini b/tox.ini
index 0528f198..347f1dd4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -75,6 +75,8 @@ commands=
 skip_install=true
 
 [testenv:docs]
-extras=.
+extras=
+    .
+    docs
 commands =
     make check-docs-ci