diff --git a/tox.ini b/tox.ini
index 389fee2..cd1879e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -108,7 +108,10 @@
 commands = {posargs}
 
 [testenv:docs]
-commands = python setup.py build_sphinx {posargs}
+# The sample config file we generate is included in the sphinxdoc, so build that first.
+commands =
+   oslo-config-generator --config-file tools/config/config-generator.tempest.conf --output-file doc/source/_static/tempest.conf
+   python setup.py build_sphinx {posargs}
 
 [testenv:pep8]
 commands =