diff --git a/Source/OpenTK/Graphics/ColorFormat.cs b/Source/OpenTK/Graphics/ColorFormat.cs
index 9298b4e4..583109e3 100644
--- a/Source/OpenTK/Graphics/ColorFormat.cs
+++ b/Source/OpenTK/Graphics/ColorFormat.cs
@@ -185,6 +185,10 @@ namespace OpenTK.Graphics
             return Red ^ Green ^ Blue ^ Alpha;
         }
 
+        /// <summary>
+        /// Returns a <see cref="System.String"/> that describes this instance.
+        /// </summary>
+        /// <returns>A <see cref="System.String"/> that describes this instance.</returns>
         public override string ToString()
         {
             return string.Format("{0} ({1})", BitsPerPixel, (IsIndexed ? " indexed" : Red.ToString() + Green.ToString() + Blue.ToString() + Alpha.ToString()));