diff --git a/docs/source/conf.py b/docs/source/conf.py
index 0a9ac82..81910a3 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -53,6 +53,7 @@
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
+    'sphinxcontrib.openapi',
     'sphinx.ext.graphviz'
 ]