diff --git a/docs.json b/docs.json
index d07abf1f..33b9ec04 100644
--- a/docs.json
+++ b/docs.json
@@ -7,6 +7,8 @@
         "lib/include.js",
         "lib/model-builder.js",
         "lib/relations.js",
+        "lib/observer.js",
+        "lib/transaction.js",
         "lib/validations.js"
     ],
     "codeSectionDepth": 4,
diff --git a/lib/observer.js b/lib/observer.js
index b260e7d6..5588ad56 100644
--- a/lib/observer.js
+++ b/lib/observer.js
@@ -3,6 +3,12 @@ var utils = require('./utils');
 
 module.exports = ObserverMixin;
 
+/**
+ * ObserverMixin class.  Use to add observe/notifyObserversOf APIs to other
+ * classes.
+ *
+ * @class ObserverMixin
+ */
 function ObserverMixin() {
 }
 
diff --git a/lib/transaction.js b/lib/transaction.js
index 8999851f..862d9e4f 100644
--- a/lib/transaction.js
+++ b/lib/transaction.js
@@ -8,6 +8,11 @@ var Transaction = require('loopback-connector').Transaction;
 
 module.exports = TransactionMixin;
 
+/**
+ * TransactionMixin class.  Use to add transaction APIs to a model class.
+ *
+ * @class TransactionMixin
+ */
 function TransactionMixin() {
 }
 
@@ -169,4 +174,6 @@ if (Transaction) {
   };
 }
 
+TransactionMixin.Transaction = Transaction;
+