diff --git a/documentation/ref-manual/structure.rst b/documentation/ref-manual/structure.rst
index c9c44bc63..ef6523ed8 100644
--- a/documentation/ref-manual/structure.rst
+++ b/documentation/ref-manual/structure.rst
@@ -345,6 +345,15 @@ This configuration file is generated by :doc:`bblock </dev-manual/bblock>` and
 contains the signatures locked by ``bblock``. By default, it does not exist
 and will be created upon the first invocation of ``bblock``.
 
+.. _structure-build-conf-auto.conf:
+
+``build/conf/auto.conf``
+------------------------
+
+This file contains configuration variables that are automatically modified by
+tools such as :oe_git:`bitbake-config-build </bitbake/tree/bin/bitbake-config-build>`.
+This file should not be modified manually.
+
 .. _structure-build-downloads:
 
 ``build/downloads/``