diff --git a/doc/source/index.rst b/doc/source/index.rst
index aeae34f1..78b2375c 100644
--- a/doc/source/index.rst
+++ b/doc/source/index.rst
@@ -5,6 +5,15 @@
 The glance_store library supports the creation, deletion and gather of data
 assets from/to a set of several, different, storage technologies.
 
+.. warning::
+   This library has been extracted from the Glance source code for the
+   specific use of the Glance and Glare projects.
+
+   The API it exposes is not stable, has some shortcomings, and is not a
+   general purpose interface. We would eventually like to change this, but for
+   now using this library outside of Glance or Glare will not be supported by
+   the core team.
+
 .. toctree::
    :maxdepth: 1
 
@@ -16,4 +25,3 @@ assets from/to a set of several, different, storage technologies.
 * :ref:`genindex`
 * :ref:`modindex`
 * :ref:`search`
-