diff --git a/docs/api/models.rst b/docs/api/models.rst
index a0e4f0b6..8be375ef 100644
--- a/docs/api/models.rst
+++ b/docs/api/models.rst
@@ -1,18 +1,28 @@
-*********************************************
-:mod:`mopidy.models` -- Immutable data models
-*********************************************
+********************
+:mod:`mopidy.models`
+********************
+
+These immutable data models are used for all data transfer within the Mopidy
+backends and between the backends and the MPD frontend. All fields are optional
+and immutable. In other words, they can only be set through the class
+constructor during instance creation.
+
+
+Data model relations
+====================
+
+.. digraph:: model_relations
+
+    Playlist -> Track [ label="has 0..n" ]
+    Track -> Album [ label="has 0..1" ]
+    Track -> Artist [ label="has 0..n" ]
+    Album -> Artist [ label="has 0..n" ]
+
+
+Data model API
+==============
 
 .. automodule:: mopidy.models
     :synopsis: Immutable data models.
     :members:
     :undoc-members:
-
-Model relations
-===============
-
-.. digraph:: model_relations
-
-    Playlist -> Track [ label="has multiple" ]
-    Track -> Album [ label="has one" ]
-    Track -> Artist [ label="has multiple" ]
-    Album -> Artist [ label="has multiple" ]