diff --git a/plug-in-development/index.html b/plug-in-development/index.html
index 4733c3f..c19b214 100644
--- a/plug-in-development/index.html
+++ b/plug-in-development/index.html
@@ -257,6 +257,15 @@
                       Plug-ins that can operate when the <code>"test"</code> task gets invoked should implement that interface.
                   </td>
               </tr>
+              <tr>
+                  <td><code><a href="https://github.com/cbeust/kobalt/blob/master/src/main/kotlin/com/beust/kobalt/api/ITestSourceDirectoryContributor.kt">
+                      ITestSourceDirectoryContributor</a></code></td>
+                  <td><a href="https://github.com/cbeust/kobalt/blob/master/src/main/kotlin/com/beust/kobalt/api/IPluginActor.kt"><code>IContributor</code></a>
+                  </td>
+                  <td>
+                      Plug-ins that add test source directories.
+                  </td>
+              </tr>
           </table>
 
 <h2 class="section" id="example">Example</h2>