diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 4db74d3..3c05512 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,10 +1,15 @@
 Release History
 ===============
 
-0.8.1 (not yet released)
-------------------------
+0.8.1 (2017-05-16)
+------------------
 * it is now possible to specify the encoding (UTF-8 or UTF-32LE) of the message
-  to hide/reveal through the command line.
+  to hide/reveal through the command line;
+* the help of the command line now displays the available choices for the
+  arguments, if it is necessary (list of available encodings, list of available
+  generators);
+* tests expected results lies now in a dedicated folder;
+* a script has been added in order to get proper exit code check for mypy.
 
 0.8 (2017-05-06)
 ----------------
diff --git a/bin/stegano-lsb b/bin/stegano-lsb
index 0cd010e..8370e61 100755
--- a/bin/stegano-lsb
+++ b/bin/stegano-lsb
@@ -20,8 +20,9 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>
 
 __author__ = "Cedric Bonhomme"
-__version__ = "$Revision: 0.6 $"
+__version__ = "$Revision: 0.7 $"
 __date__ = "$Date: 2016/08/04 $"
+__revision__ = "$Date: 2017/05/16 $"
 __license__ = "GPLv3"
 
 try:
@@ -40,7 +41,8 @@ parser_hide = subparsers.add_parser('hide', help='hide help')
 # Original image
 parser_hide.add_argument("-i", "--input", dest="input_image_file",
                 required=True, help="Input image file.")
-parser_hide.add_argument("-e", "--encoding", dest="encoding", default="UTF-8",
+parser_hide.add_argument("-e", "--encoding", dest="encoding",
+                choices=tools.ENCODINGS.keys(),
                 help="Specify the encoding of the message to hide." +
                 " UTF-8 (default) or UTF-32LE.")
 
@@ -61,7 +63,8 @@ parser_hide.add_argument("-o", "--output", dest="output_image_file",
 parser_reveal = subparsers.add_parser('reveal', help='reveal help')
 parser_reveal.add_argument("-i", "--input", dest="input_image_file",
                 required=True, help="Input image file.")
-parser_reveal.add_argument("-e", "--encoding", dest="encoding", default="UTF-8",
+parser_reveal.add_argument("-e", "--encoding", dest="encoding",
+                choices=tools.ENCODINGS.keys(),
                 help="Specify the encoding of the message to reveal." +
                 " UTF-8 (default) or UTF-32LE.")
 parser_reveal.add_argument("-o", dest="secret_binary",
diff --git a/bin/stegano-lsb-set b/bin/stegano-lsb-set
index 24eb453..c1c3f1f 100755
--- a/bin/stegano-lsb-set
+++ b/bin/stegano-lsb-set
@@ -20,11 +20,12 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>
 
 __author__ = "Cedric Bonhomme"
-__version__ = "$Revision: 0.6 $"
+__version__ = "$Revision: 0.7 $"
 __date__ = "$Date: 2016/03/18 $"
-__revision__ = "$Date: 2016/08/04 $"
+__revision__ = "$Date: 2017/05/16 $"
 __license__ = "GPLv3"
 
+import inspect
 import crayons
 
 try:
@@ -44,9 +45,15 @@ parser_hide = subparsers.add_parser('hide', help='hide help')
 # Original image
 parser_hide.add_argument("-i", "--input", dest="input_image_file",
                 required=True, help="Input image file.")
+parser_hide.add_argument("-e", "--encoding", dest="encoding",
+                choices=tools.ENCODINGS.keys(),
+                help="Specify the encoding of the message to hide." +
+                " UTF-8 (default) or UTF-32LE.")
 
 # Generator
 parser_hide.add_argument("-g", "--generator", dest="generator_function",
+                choices=[generator[0] for generator in \
+                            inspect.getmembers(generators, inspect.isfunction)],
                 required=True, help="Generator")
 
 group_secret = parser_hide.add_mutually_exclusive_group(required=True)
@@ -66,7 +73,13 @@ parser_hide.add_argument("-o", "--output", dest="output_image_file",
 parser_reveal = subparsers.add_parser('reveal', help='reveal help')
 parser_reveal.add_argument("-i", "--input", dest="input_image_file",
                 required=True, help="Input image file.")
+parser_reveal.add_argument("-e", "--encoding", dest="encoding",
+                choices=tools.ENCODINGS.keys(),
+                help="Specify the encoding of the message to reveal." +
+                " UTF-8 (default) or UTF-32LE.")
 parser_reveal.add_argument("-g", "--generator", dest="generator_function",
+                choices=[generator[0] for generator in \
+                            inspect.getmembers(generators, inspect.isfunction)],
                 required=True, help="Generator")
 parser_reveal.add_argument("-o", dest="secret_binary",
                 help="Output for the binary secret (Text or any binary file).")
@@ -119,7 +132,6 @@ elif arguments.command == 'reveal':
         print(secret)
 
 elif arguments.command == 'list-generators':
-    import inspect
     all_generators = inspect.getmembers(generators, inspect.isfunction)
     for generator in all_generators:
         print('Generator id:')