diff --git a/org.fortiss.tooling.base.ui/html/developer/.ratings b/org.fortiss.tooling.base.ui/html/developer/.ratings
index 2936766b23ecd9b6c0fa605b9a838b708ac6342b..4e32de0754d56c9a1ba7eb80795de857620d8cfd 100644
--- a/org.fortiss.tooling.base.ui/html/developer/.ratings
+++ b/org.fortiss.tooling.base.ui/html/developer/.ratings
@@ -1 +1 @@
-documentation.html 537e8465aeba8ae2710474486b811f59a3dbd45c RED
+documentation.html 2588c92dc58129eb36ca852901128599f9140ffa YELLOW
diff --git a/org.fortiss.tooling.base.ui/html/developer/documentation.html b/org.fortiss.tooling.base.ui/html/developer/documentation.html
index 537e8465aeba8ae2710474486b811f59a3dbd45c..2588c92dc58129eb36ca852901128599f9140ffa 100644
--- a/org.fortiss.tooling.base.ui/html/developer/documentation.html
+++ b/org.fortiss.tooling.base.ui/html/developer/documentation.html
@@ -1,4 +1,30 @@
 <html><body>
 <H1>Developer Documentation for <I>org.fortiss.tooling.base.ui</I></H1>
-<P>// TODO
+<p>This plugin provides a base implementation for graphical editors using the GEF framework
+(to be replaced with a JavaFX based implementation).</p>
+
+<p>It contains the following main packages:
+<ul>
+<li><code>annotation</code>:
+GUI support of annotation framework.
+<ul>
+<li><code>editingsupport</code>: contains editing support to edit annotations into the generic table-based annotation view.</li> 
+<li><code>labelprovider</code>: contains label providers support to display annotations in the generic table-based annotation view.</li> 
+<li><code>view</code>: provides abstract base classes and a generic table-based view part to display and edit annotations.</li> 
+</ul>
+</li>
+<li><code>databinding</code>: Eclipse data binding support.</li>
+<li><code>dialog</code>: Basic dialog classes.</li>
+<li><code>dnd</code>: JFace and GEF-based drag'n'drop.</li>
+<li><code>editor</code>: various (model) editors</li>
+<li><code>editpart</code>: GEF edit part base classes.</li>
+<li><code>fieldassist</code>: Auto-completion support.</li>
+<li><code>javafx</code>: JavaFX-based UI support (under development).</li>
+<li><code>layout</code>: Diagram layout configurations, including automatic layout.</li>
+<li><code>utils</code>: Utility classes.</li>
+<li><code>viewers</code>: Editor editing support and label providers.</li>
+
+</ul>
+
+</p>
 </body></html>