diff --git a/tiramisu/api.py b/tiramisu/api.py
index bbc2ba6..521176d 100644
--- a/tiramisu/api.py
+++ b/tiramisu/api.py
@@ -83,7 +83,7 @@ def display_count():
 class CommonTiramisu(object):
     allow_optiondescription = True
 
-    def get_option(self):
+    def _get_option(self):
         option = self.config_bag.option
         if option is None:
             option = self.subconfig.cfgimpl_get_description().impl_getchild(self.name,
@@ -119,7 +119,7 @@ class CommonTiramisuOption(CommonTiramisu):
             self._unrestraint_not_allowed(self.config_bag.force_unrestraint)
 
     def _test_slave_index(self):
-        option = self.get_option()
+        option = self._get_option()
         if not option.impl_is_optiondescription() and self.index is None and \
                 option.impl_is_master_slaves('slave'):
             raise APIError('index must be set with a slave option')
@@ -155,63 +155,96 @@ class TiramisuOptionOption(CommonTiramisuOption):
     slave_need_index = False
 
     @count
-    def ismulti(self):
+    def get(self):
+        return self._get_option()
+
+    @count
+    def _ismulti(self):
         """test if option could have multi value"""
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_is_multi()
     
     @count
-    def issubmulti(self):
+    def _issubmulti(self):
         """test if option could have submulti value"""
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_is_submulti()
 
     @count
     def ismasterslaves(self):
         """test if option is a master or a slave"""
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_is_master_slaves()
 
     @count
-    def ismaster(self):
+    def _ismaster(self):
         """test if option is a master"""
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_is_master_slaves('master')
 
     @count
-    def isslave(self):
+    def _isslave(self):
         """test if option is a slave"""
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_is_master_slaves('slave')
 
     @count
-    def getname(self):
-        option = self.get_option()
+    def name(self):
+        option = self._get_option()
         return option.impl_getname()
 
     @count
-    def getdoc(self):
-        option = self.get_option()
+    def doc(self):
+        option = self._get_option()
         return option.impl_get_display_name()
 
     @count
-    def default(self):
-        option = self.get_option()
+    def _default(self):
+        option = self._get_option()
         return option.impl_getdefault()
 
     @count
-    def defaultmulti(self):
-        option = self.get_option()
+    def _defaultmulti(self):
+        option = self._get_option()
         return option.impl_getdefault_multi()
 
     @count
     def has_dependency(self, self_is_dep=True):
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_has_dependency(self_is_dep)
 
+    @count
+    def _consistencies(self):
+        option = self._get_option()
+        return option.get_consistencies()
+
+    @count
+    def _callbacks(self):
+        option = self._get_option()
+        return option.impl_get_callback()
+
+    @count
+    def requires(self):
+        option = self._get_option()
+        return option.impl_getrequires()
+
+    def __getattr__(self, name):
+        if not self._get_option().impl_is_optiondescription() and name != 'get_option':
+            subkey = '_' + name
+            if subkey in dir(self):
+                func = getattr(self, subkey)
+                if callable(func):
+                    return func
+        raise APIError(_('{} is unknown').format(name))
+
+    def isoptiondescription(self):
+        return self._get_option().impl_is_optiondescription()
+
+
 
 class TiramisuOptionOwner(CommonTiramisuOption):
     """manager option's owner"""
+    allow_unrestraint = True
 
     def __init__(self,
                  name,
@@ -230,7 +263,7 @@ class TiramisuOptionOwner(CommonTiramisuOption):
     @count
     def get(self):
         """get owner for a specified option"""
-        self.get_option()
+        self._get_option()
         return self.values.getowner(self.path,
                                     self.index,
                                     self.config_bag)
@@ -238,7 +271,7 @@ class TiramisuOptionOwner(CommonTiramisuOption):
     @count
     def isdefault(self):
         """is option has defaut value"""
-        self.get_option()
+        self._get_option()
         return self.values.is_default_owner(self.path,
                                             self.index,
                                             self.config_bag)
@@ -246,7 +279,7 @@ class TiramisuOptionOwner(CommonTiramisuOption):
     @count
     def set(self, owner):
         """get owner for a specified option"""
-        self.get_option()
+        self._get_option()
         if TIRAMISU_VERSION == 2:
             if owner in ['default', 'forced', 'meta']:
                 raise ConfigError()
@@ -263,7 +296,6 @@ class TiramisuOptionOwner(CommonTiramisuOption):
 
 class TiramisuOptionProperty(CommonTiramisuOption):
     """manager option's property"""
-    #allow_unrestraint = True
     allow_optiondescription = True
     allow_unrestraint = True
     slave_need_index = False
@@ -283,7 +315,7 @@ class TiramisuOptionProperty(CommonTiramisuOption):
 
     @count
     def get(self):
-        self.get_option()
+        self._get_option()
         self._test_slave_index()
         properties = self.settings.getproperties(self.path,
                                                  self.index,
@@ -295,14 +327,14 @@ class TiramisuOptionProperty(CommonTiramisuOption):
     @count
     def add(self, prop):
         #FIXME not index !!
-        self.get_option()
+        self._get_option()
         self.settings.addproperty(self.path,
                                   prop,
                                   self.config_bag)
 
     @count
     def pop(self, prop):
-        self.get_option()
+        self._get_option()
         self.settings.popproperty(self.path,
                                   prop,
                                   self.config_bag)
@@ -311,7 +343,7 @@ class TiramisuOptionProperty(CommonTiramisuOption):
     def reset(self):
         """reset all personalised properties
         """
-        self.get_option()
+        self._get_option()
         self.settings.reset(opt=self.config_bag.option,
                             path=self.path)
 
@@ -341,14 +373,14 @@ class TiramisuOptionPermissive(CommonTiramisuOption):
         if TIRAMISU_VERSION == 2:
             args = [self.setting_properties, self.path]
         else:
-            args = [self.get_option(), self.path]
+            args = [self._get_option(), self.path]
         return self.settings.getpermissive(*args)
 
     @count
     def set(self, permissives):
         if TIRAMISU_VERSION == 2:
             permissive = tuple(permissives)
-        self.settings.setpermissive(opt=self.get_option(),
+        self.settings.setpermissive(opt=self._get_option(),
                                     path=self.path,
                                     permissives=permissives)
 
@@ -360,21 +392,23 @@ class TiramisuOptionPermissive(CommonTiramisuOption):
 
 
 class TiramisuOptionInformation(CommonTiramisuOption):
+    allow_unrestraint = True
     allow_optiondescription = True
 
     @count
     def get(self, name, default=undefined):
-        option = self.get_option()
+        option = self._get_option()
         return option.impl_get_information(name, default)
 
 
 class TiramisuOptionValue(CommonTiramisuOption):
     """manager option's value"""
     slave_need_index = False
+    allow_unrestraint = True
 
     @count
     def get(self):
-        self.get_option()
+        self._get_option()
         self._test_slave_index()
         settings = self.config_bag.config.cfgimpl_get_settings()
         value = self.subconfig.getattr(self.name,
@@ -387,7 +421,7 @@ class TiramisuOptionValue(CommonTiramisuOption):
     @count
     def set(self, value):
         """set a value for a specified option"""
-        self.get_option()
+        self._get_option()
         self._test_slave_index()
         values = self.config_bag.config.cfgimpl_get_values()
         if isinstance(value, list):
@@ -410,7 +444,7 @@ class TiramisuOptionValue(CommonTiramisuOption):
     def _pop(self, index):
         """pop value for a specified master values
         """
-        self.get_option()
+        self._get_option()
         self.config_bag.config.delattr(self.path,
                                        index,
                                        self.config_bag)
@@ -418,7 +452,7 @@ class TiramisuOptionValue(CommonTiramisuOption):
     @count
     def reset(self):
         """reset value for a value"""
-        self.get_option()
+        self._get_option()
         self._test_slave_index()
         self.config_bag.config.delattr(self.path,
                                        self.index,
@@ -426,7 +460,7 @@ class TiramisuOptionValue(CommonTiramisuOption):
 
     @count
     def _len(self):
-        self.get_option()
+        self._get_option()
         subconfig_path = self.path.rsplit('.', 1)[0]
         subconfig = self.config.getattr(subconfig_path,
                                         None,
@@ -434,11 +468,11 @@ class TiramisuOptionValue(CommonTiramisuOption):
         return subconfig.cfgimpl_get_length()
 
     def __getattr__(self, name):
-        if name == 'list' and isinstance(self.get_option(), ChoiceOption):
+        if name == 'list' and isinstance(self._get_option(), ChoiceOption):
             return self._list
-        elif name == 'pop' and self.get_option().impl_is_master_slaves('master'):
+        elif name == 'pop' and self._get_option().impl_is_master_slaves('master'):
             return self._pop
-        elif name == 'len' and self.get_option().impl_is_master_slaves('slave'):
+        elif name == 'len' and self._get_option().impl_is_master_slaves('slave'):
             return self._len
         raise APIError(_('{} is unknown').format(name))
 
@@ -491,11 +525,11 @@ class TiramisuOption(CommonTiramisu):
                                            self.config_bag)
         elif subfunc == 'help':
             return self._help()
-        elif subfunc == 'make_dict' and self.get_option().impl_is_optiondescription():
+        elif subfunc == 'make_dict' and self._get_option().impl_is_optiondescription():
             return self._make_dict
-        elif subfunc == 'list' and self.get_option().impl_is_optiondescription():
+        elif subfunc == 'list' and self._get_option().impl_is_optiondescription():
             return self._list
-        elif subfunc == 'group_type' and self.get_option().impl_is_optiondescription():
+        elif subfunc == 'group_type' and self._get_option().impl_is_optiondescription():
             return self._group_type
         else:
             raise APIError(_('please specify a valid sub function ({})').format(subfunc))
@@ -516,7 +550,7 @@ class TiramisuOption(CommonTiramisu):
 
     @count
     def group_type(self):
-        return self.get_option().impl_get_group_type()
+        return self._get_option().impl_get_group_type()
 
     @count
     def _list(self, type='all', group_type=None):
@@ -682,11 +716,11 @@ class TiramisuContextOption(TiramisuContext):
                                            type_=type,
                                            config_bag=self.config_bag)
 
-    @count
-    def get(self, path):
-        return self.config_bag.config.unwrap_from_path(path,
-                                                       None,
-                                                       self.config_bag)
+    #@count
+    #def get(self, path):
+    #    return self.config_bag.config.unwrap_from_path(path,
+    #                                                   None,
+    #                                                   self.config_bag)
 
     @count
     def make_dict(self,
@@ -732,6 +766,8 @@ class TiramisuDispatcherConfig(TiramisuContextConfig):
 
 class TiramisuDispatcherOption(TiramisuContextOption):
     def __call__(self, path, index=None):
+        if path is None:
+            return self
         config_bag = self.config_bag.copy()
         validate = not config_bag.force_unrestraint
         #config_bag.validate = validate
diff --git a/tiramisu/config.py b/tiramisu/config.py
index 406f94f..5e77201 100644
--- a/tiramisu/config.py
+++ b/tiramisu/config.py
@@ -238,13 +238,14 @@ class SubConfig(object):
             nconfig_bag.option = opt
             name = opt.impl_getname()
             subpath = self._get_subpath(name)
-            try:
-                context.cfgimpl_get_settings().validate_properties(subpath,
-                                                                   None,
-                                                                   nconfig_bag)
-                yield name
-            except PropertiesOptionError:
-                pass
+            if nconfig_bag.setting_properties is not None:
+                try:
+                    context.cfgimpl_get_settings().validate_properties(subpath,
+                                                                       None,
+                                                                       nconfig_bag)
+                except PropertiesOptionError:
+                    continue
+            yield name
 
     # ______________________________________________________________________
 
diff --git a/tiramisu/option/masterslave.py b/tiramisu/option/masterslave.py
index d6e97bb..a09437f 100644
--- a/tiramisu/option/masterslave.py
+++ b/tiramisu/option/masterslave.py
@@ -175,5 +175,5 @@ class MasterSlaves(OptionDescription):
                 raise SlaveError(_('cannot reduce length of the master "{}"'
                                    '').format(option.impl_get_display_name()))
 
-    def is_masterslaves(self):
+    def impl_is_master_slaves(self):
         return True
diff --git a/tiramisu/option/option.py b/tiramisu/option/option.py
index cd16fc7..c962e1d 100644
--- a/tiramisu/option/option.py
+++ b/tiramisu/option/option.py
@@ -484,7 +484,7 @@ class Option(OnlyOption):
                 consistencies = descr._cache_consistencies.get(option)
         else:
             # is no context, get consistencies in option
-            consistencies = option._get_consistencies()
+            consistencies = option.get_consistencies()
         if consistencies is not None:
             for cons_id, func, all_cons_opts, params in consistencies:
                 warnings_only = params.get('warnings_only', False)
@@ -759,7 +759,7 @@ class Option(OnlyOption):
     def _del_consistency(self):
         self._consistencies.pop(-1)
 
-    def _get_consistencies(self):
+    def get_consistencies(self):
         return getattr(self, '_consistencies', STATIC_TUPLE)
 
     def _has_consistencies(self, context):
diff --git a/tiramisu/option/optiondescription.py b/tiramisu/option/optiondescription.py
index 00f97cd..9881576 100644
--- a/tiramisu/option/optiondescription.py
+++ b/tiramisu/option/optiondescription.py
@@ -76,7 +76,7 @@ class CacheOptionDescription(BaseOption):
                 is_multi = option.impl_is_multi()
                 if not option.impl_is_symlinkoption() and 'force_store_value' in option.impl_getproperties():
                     force_store_values.append((subpath, option))
-                for cons_id, func, all_cons_opts, params in option._get_consistencies():
+                for cons_id, func, all_cons_opts, params in option.get_consistencies():
                     option._valid_consistencies(all_cons_opts[1:], init=False)
                     if func not in ALLOWED_CONST_LIST and is_multi:
                         is_masterslaves = option.impl_is_master_slaves()
@@ -473,7 +473,7 @@ class OptionDescription(OptionDescriptionWalk):
         # the group_type is useful for filtering OptionDescriptions in a config
         self._group_type = groups.default
 
-    def is_masterslaves(self):
+    def impl_is_master_slaves(self):
         return False
 
     def impl_getdoc(self):
diff --git a/tiramisu/option/symlinkoption.py b/tiramisu/option/symlinkoption.py
index 02b729a..bad6ece 100644
--- a/tiramisu/option/symlinkoption.py
+++ b/tiramisu/option/symlinkoption.py
@@ -42,7 +42,8 @@ class SymLinkOption(OnlyOption):
                     name):
         return getattr(self._opt, name)
 
-    def impl_has_dependency(self, self_is_dep=True):
+    def impl_has_dependency(self,
+                            self_is_dep=True):
         """If self_is_dep is True, it has dependency (self._opt), so return True
         if self_is_dep is False, cannot has validation or callback, so return False
         """
@@ -78,10 +79,11 @@ class SymLinkOption(OnlyOption):
     #def _is_subdyn(self):
     #    return getattr(self._opt, '_subdyn', None) is not None
 
-    def _get_consistencies(self):
+    def get_consistencies(self):
         return ()
 
-    def _has_consistencies(self, context):
+    def _has_consistencies(self,
+                           context):
         return option._opt._has_consistencies(context)
 
 
diff --git a/tiramisu/value.py b/tiramisu/value.py
index 29b5229..0d05d1d 100644
--- a/tiramisu/value.py
+++ b/tiramisu/value.py
@@ -705,7 +705,7 @@ class Values(object):
         config_bag.force_permissive = True
         config_bag.display_warnings = False
         def _mandatory_warnings(description, currpath, config):
-            is_masterslaves = description.is_masterslaves()
+            is_masterslaves = description.impl_is_master_slaves()
             lenmaster = None
             optmaster = None
             pathmaster = None