diff --git a/sop-java/src/main/java/sop/enums/SignAs.java b/sop-java/src/main/java/sop/enums/SignAs.java
index fcd79f4..f7f3671 100644
--- a/sop-java/src/main/java/sop/enums/SignAs.java
+++ b/sop-java/src/main/java/sop/enums/SignAs.java
@@ -5,6 +5,13 @@
 package sop.enums;
 
 public enum SignAs {
+    /**
+     * Signature is made over the binary message.
+     */
     Binary,
+
+    /**
+     * Signature is made over the message in text mode.
+     */
     Text
 }