diff --git a/websocket-sharp/Server/WebSocketSessionManager.cs b/websocket-sharp/Server/WebSocketSessionManager.cs
index fac22909..b18c8a27 100644
--- a/websocket-sharp/Server/WebSocketSessionManager.cs
+++ b/websocket-sharp/Server/WebSocketSessionManager.cs
@@ -1196,26 +1196,82 @@ namespace WebSocketSharp.Server
     }
 
     /// <summary>
-    /// Sends binary data from the specified <see cref="Stream"/> asynchronously to
-    /// the client on the session with the specified <paramref name="id"/>.
+    /// Sends the data from <paramref name="stream"/> asynchronously to
+    /// the client using the specified session.
     /// </summary>
     /// <remarks>
-    /// This method doesn't wait for the send to be complete.
+    ///   <para>
+    ///   The data is sent as the binary data.
+    ///   </para>
+    ///   <para>
+    ///   This method does not wait for the send to be complete.
+    ///   </para>
     /// </remarks>
     /// <param name="stream">
-    /// A <see cref="Stream"/> from which contains the binary data to send.
+    /// A <see cref="Stream"/> instance from which to read the data to send.
     /// </param>
     /// <param name="length">
-    /// An <see cref="int"/> that represents the number of bytes to send.
+    /// An <see cref="int"/> that specifies the number of bytes to send.
     /// </param>
     /// <param name="id">
-    /// A <see cref="string"/> that represents the ID of the session to find.
+    /// A <see cref="string"/> that represents the ID of the session.
     /// </param>
     /// <param name="completed">
-    /// An <c>Action&lt;bool&gt;</c> delegate that references the method(s) called when
-    /// the send is complete. A <see cref="bool"/> passed to this delegate is <c>true</c>
-    /// if the send is complete successfully.
+    ///   <para>
+    ///   An <c>Action&lt;bool&gt;</c> delegate or <see langword="null"/>
+    ///   if not needed.
+    ///   </para>
+    ///   <para>
+    ///   The delegate invokes the method called when the send is complete.
+    ///   </para>
+    ///   <para>
+    ///   <c>true</c> is passed to the method if the send has done with
+    ///   no error; otherwise, <c>false</c>.
+    ///   </para>
     /// </param>
+    /// <exception cref="ArgumentNullException">
+    ///   <para>
+    ///   <paramref name="id"/> is <see langword="null"/>.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   <paramref name="stream"/> is <see langword="null"/>.
+    ///   </para>
+    /// </exception>
+    /// <exception cref="ArgumentException">
+    ///   <para>
+    ///   <paramref name="id"/> is an empty string.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   The session could not be found.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   <paramref name="stream"/> cannot be read.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   <paramref name="length"/> is less than 1.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   No data could be read from <paramref name="stream"/>.
+    ///   </para>
+    /// </exception>
+    /// <exception cref="InvalidOperationException">
+    /// The current state of the WebSocket connection is not Open.
+    /// </exception>
     public void SendToAsync (
       Stream stream, int length, string id, Action<bool> completed
     )