diff --git a/docs/source/index.rst b/docs/source/index.rst
index c21b83e..d2f9b46 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -37,6 +37,8 @@ API
 ====
 
 .. toctree::
+    :maxdepth: 3
+
     api/components
     api/architectures
     api/multiscale_architectures