diff --git a/dcos/cli/config.py b/dcos/cli/config.py
index 1602c9d..3465730 100644
--- a/dcos/cli/config.py
+++ b/dcos/cli/config.py
@@ -46,6 +46,12 @@ def main():
 
 
 def _save_config_file(config_path, toml_config):
+    """Save dictionary as TOML file
+
+    :param config_path: Path to configuration file.
+    :type config_path: str or unicode
+    """
+
     serial = toml.dumps(toml_config)
     with open(config_path, 'w') as config_file:
         config_file.write(serial)
diff --git a/dcos/cli/dcos.py b/dcos/cli/dcos.py
index 5e3d894..a1b07e0 100644
--- a/dcos/cli/dcos.py
+++ b/dcos/cli/dcos.py
@@ -44,6 +44,13 @@ def main():
 
 
 def _list_external_subcommands(dcos_path):
+    """List external subcommands
+
+    :param dcos_path: Path to the directory where the dcos cli is installed
+    :type dcos_path: str
+    :returns: List of subcommands
+    :rtype: list of str
+    """
     prefix = 'dcos-'
 
     return [filename[len(prefix):]
@@ -59,6 +66,13 @@ def _list_external_subcommands(dcos_path):
 
 
 def _external_command_documentation(commands):
+    """Gather sub-command summary
+
+    :param commands: List of subcommand
+    :type comands: list of str
+    :returns: Returns a list of subcommand and their summary
+    :rtype: list of (str, str)
+    """
     def info(commnand):
         return subprocess.check_output(
             ['dcos-{}'.format(command), command, 'info'])
@@ -67,6 +81,12 @@ def _external_command_documentation(commands):
 
 
 def _is_valid_configuration():
+    """Validates running environment
+
+    :returns: True if the environment is configure correctly, False otherwise.
+    :rtype: bool
+    """
+
     dcos_path = os.environ.get(constants.DCOS_PATH_ENV)
     if dcos_path is None:
         msg = 'Environment variable {!r} not set to the DCOS CLI path.'
diff --git a/dcos/cli/marathon.py b/dcos/cli/marathon.py
index 95b1ca9..a001edd 100644
--- a/dcos/cli/marathon.py
+++ b/dcos/cli/marathon.py
@@ -35,11 +35,26 @@ def main():
 
 
 def _info():
+    """Print marathon cli information
+
+    :returns: Process status
+    :rtype: int
+    """
+
     print('Deploy and manage containers for Mesos')
     return 0
 
 
 def _start(app_resource_path, config):
+    """Starts an application with Marathon
+
+    :param app_resource_path: Path to the application resource
+    :type app_resource_path: str
+    :param config: Configuration dictionary
+    :type config: config.Toml
+    :returns: Process status
+    :rtype: int
+    """
     client = marathon.Client(config['marathon.host'], config['marathon.port'])
 
     with open(app_resource_path) as app_resource_file:
diff --git a/dcos/config.py b/dcos/config.py
index ddff133..cfab411 100644
--- a/dcos/config.py
+++ b/dcos/config.py
@@ -10,12 +10,21 @@ class Toml(collections.MutableMapping):
     def __init__(self, dictionary):
         """Constructs interface for managing configurations
 
-        :config_path: (string) Path to the TOML configuration file
-
+        :param dictionary: Configuration dictionary
+        :type dictionary: dict
         """
+
         self._dictionary = dictionary
 
     def __getitem__(self, path):
+        """Get the value for a path
+
+        :param path: Path to the value. E.g. 'path.to.value'
+        :type path: str
+        :returns: Value stored at the given path
+        :rtype: double, int, str, list or dict
+        """
+
         config = self._dictionary
 
         for section in path.split('.'):
@@ -27,12 +36,32 @@ class Toml(collections.MutableMapping):
             return config
 
     def __iter__(self):
+        """Returns iterator
+
+        :returns: Dictionary iterator
+        :rtype: iterator
+        """
+
         return iter(self._dictionary)
 
     def __len__(self):
+        """Length of the toml configuration
+
+        :returns: The length of the dictionary
+        :rtype: int
+        """
+
         return len(self._dictionary)
 
     def __setitem__(self, path, value):
+        """Set the path to a value
+
+        :param path: Path to set
+        :type path: str
+        :param value: Value to store
+        :type value: double, int, str, list or dict
+        """
+
         config = self._dictionary
 
         sections = path.split('.')
@@ -42,6 +71,11 @@ class Toml(collections.MutableMapping):
         config[sections[-1]] = value
 
     def __delitem__(self, path):
+        """Delete value stored at path
+
+        :param path: Path to delete
+        :type path: str
+        """
         config = self._dictionary
 
         sections = path.split('.')
@@ -52,5 +86,13 @@ class Toml(collections.MutableMapping):
 
     @classmethod
     def load_from_path(class_, path):
+        """Loads a TOML file from the path
+
+        :param path: Path to the TOML file
+        :type path: str
+        :returns: Dictionary for the configuration file
+        :rtype: Toml
+        """
+
         with open(path) as config_file:
             return Toml(toml.loads(config_file.read()))
diff --git a/dcos/errors.py b/dcos/errors.py
index e62e742..c8df35e 100644
--- a/dcos/errors.py
+++ b/dcos/errors.py
@@ -5,4 +5,10 @@ class Error(object):
 
     @abc.abstractmethod
     def error(self):
+        """Creates an error message
+
+        :returns: The error message
+        :rtype: str
+        """
+
         raise NotImplementedError
diff --git a/dcos/marathon.py b/dcos/marathon.py
index f089bff..6113084 100644
--- a/dcos/marathon.py
+++ b/dcos/marathon.py
@@ -9,15 +9,25 @@ class Client(object):
     def __init__(self, host, port):
         """Constructs interface for talking Marathon.
 
-        :param host: (string) Host for the Marathon server.
-        :param port: (int) Port for the Marathon server.
-
+        :param host: Host for the Marathon server.
+        :type host: str
+        :param port: Port for the Marathon server.
+        :type port: int
         """
+
         self._url_pattern = "http://{host}:{port}/{path}"
         self._host = host
         self._port = port
 
     def _create_url(self, path):
+        """Creates the url from the provided path
+
+        :param path: Url path
+        :type path: str
+        :return: Constructed url
+        :rtype: str
+        """
+
         return self._url_pattern.format(
             host=self._host,
             port=self._port,
@@ -26,9 +36,12 @@ class Client(object):
     def start_app(self, app_resource):
         """Create and start a new application
 
-        :param app_resource: (dict) Application resource
-
+        :param app_resource: Application resource
+        :type app_resource: dict, bytes, or file
+        :returns: Status of trying to start the application
+        :rtype: (bool, Error)
         """
+
         url = self._create_url('v2/apps')
         response = requests.post(url, data=app_resource)
 
@@ -44,7 +57,19 @@ class Client(object):
 
 class Error(errors.Error):
     def __init__(self, message):
+        """Constructs error for Marathon calls
+
+        :param message: Error message
+        :type message: str
+        """
+
         self._message = message
 
     def error(self):
+        """Return error message
+
+        :returns: The error message
+        :rtype: str
+        """
+
         return self._message
diff --git a/dcos/options.py b/dcos/options.py
index 3a60d26..2c762ae 100644
--- a/dcos/options.py
+++ b/dcos/options.py
@@ -1,4 +1,14 @@
 def extend_usage_docopt(doc, command_summaries):
+    """Extends usage information with sub-command summaries
+
+    :param doc: Usage documentation
+    :type doc: str
+    :param command_summaries: Commands and their summaries
+    :type command_summaries: list of (str, str)
+    :returns: Usage documetation with the sub-command summaries
+    :rtype: str
+    """
+
     doc += '\nThe dcos commands are:'
     for command, summary in command_summaries:
         doc += '\n\t{:15}\t{}'.format(command, summary.strip())