diff --git a/tests/test_leadership.py b/tests/test_leadership.py
index e70a110..229d0fd 100644
--- a/tests/test_leadership.py
+++ b/tests/test_leadership.py
@@ -788,6 +788,19 @@ def test_values_with_leader_and_followers_leader_pop():
 #    assert not list_sessions()
 
 
+def test_values_with_leader_and_followers_leader_pop_default_value():
+    ip_admin_eth0 = StrOption('ip_admin_eth0', "ip réseau autorisé", default=["192.168.230.145", "192.168.230.146"], multi=True, properties=('notunique',))
+    netmask_admin_eth0 = StrOption('netmask_admin_eth0', "masque du sous-réseau", default_multi="255.255.255.0", multi=True)
+    interface1 = Leadership('ip_admin_eth0', '', [ip_admin_eth0, netmask_admin_eth0])
+    od1 = OptionDescription('toto', '', [interface1])
+    cfg = Config(od1)
+    cfg.property.read_write()
+    cfg.option('ip_admin_eth0.ip_admin_eth0').value.pop(0)
+    compare(cfg.value.exportation(), {'ip_admin_eth0.ip_admin_eth0': {None: [['192.168.230.146'], 'user']}})
+    assert cfg.option('ip_admin_eth0.ip_admin_eth0').value.get() == ["192.168.230.146"]
+    assert cfg.option('ip_admin_eth0.netmask_admin_eth0', 0).value.get() == '255.255.255.0'
+
+
 def test_follower_unique():
     ip_admin_eth0 = StrOption('ip_admin_eth0', "ip réseau autorisé", multi=True)
     netmask_admin_eth0 = StrOption('netmask_admin_eth0', "masque du sous-réseau", multi=True, properties=('unique',))
diff --git a/tests/test_option_callback.py b/tests/test_option_callback.py
index da37b60..f54c186 100644
--- a/tests/test_option_callback.py
+++ b/tests/test_option_callback.py
@@ -945,7 +945,7 @@ def test_consistency_leader_and_followers_leader_mandatory_transitive():
     try:
         cfg.option('val1.val2', 0).value.get()
     except PropertiesOptionError as error:
-        assert str(error) == str(_('cannot access to {0} {1} because has {2} {3}').format('option', '"val2"', _('property'), '"disabled"'))
+        assert str(error) == str(_('cannot access to {0} {1} at index "{2}" because has {3} {4}').format('option', '"val2"', 0, _('property'), '"disabled"'))
     else:
         raise Exception('must raises')
     assert list(cfg.value.mandatory()) == []
diff --git a/tiramisu/api.py b/tiramisu/api.py
index 2da429b..03e744f 100644
--- a/tiramisu/api.py
+++ b/tiramisu/api.py
@@ -271,9 +271,18 @@ class _TiramisuOptionWalk:
 
 class _TiramisuOptionOptionDescription:
     """Manage option"""
+
     _validate_properties = False
 
-    @option_type(["optiondescription", "option", "with_or_without_index", "symlink", "allow_dynoption"])
+    @option_type(
+        [
+            "optiondescription",
+            "option",
+            "with_or_without_index",
+            "symlink",
+            "allow_dynoption",
+        ]
+    )
     def get(self):
         """Get Tiramisu option"""
         return self._subconfig.option
@@ -291,11 +300,14 @@ class _TiramisuOptionOptionDescription:
     @option_type(["optiondescription", "option", "with_or_without_index", "symlink"])
     def description(
         self,
+        with_quote: bool = False,
         uncalculated: bool = False,
     ):
         """Get option description"""
         if not uncalculated:
-            return self._subconfig.option.impl_get_display_name(self._subconfig)
+            return self._subconfig.option.impl_get_display_name(
+                self._subconfig, with_quote=with_quote
+            )
         return self._subconfig.option._get_information(
             self._subconfig,
             "doc",
@@ -354,7 +366,7 @@ class _TiramisuOptionOptionDescription:
         if option.impl_is_optiondescription():
             return "optiondescription"
         if only_self and option.impl_is_symlinkoption():
-            return 'symlink'
+            return "symlink"
         return option.get_type()
 
     @option_type(["option", "symlink", "with_or_without_index"])
@@ -808,11 +820,7 @@ class TiramisuOptionValue(CommonTiramisuOption, _TiramisuODGet):
             and option.impl_is_leader()
             and len(value) < self._subconfig.parent.get_length_leadership()
         ):
-            raise LeadershipError(
-                _("cannot reduce length of the leader {}" "").format(
-                    option.impl_get_display_name(self._subconfig, with_quote=True)
-                )
-            )
+            raise LeadershipError(self._subconfig, "leadership-reduce")
         values = self._config_bag.context.get_values()
         return values.set_value(self._subconfig, value)
 
diff --git a/tiramisu/autolib.py b/tiramisu/autolib.py
index 3a448cf..f31b5c5 100644
--- a/tiramisu/autolib.py
+++ b/tiramisu/autolib.py
@@ -22,7 +22,15 @@ from typing import Any, Optional, Union, Callable, Dict, List
 from itertools import chain
 import weakref
 
-from .error import PropertiesOptionError, ConfigError, LeadershipError, ValueWarning, CancelParam, display_list, errors
+from .error import (
+    PropertiesOptionError,
+    ConfigError,
+    LeadershipError,
+    ValueWarning,
+    CancelParam,
+    display_list,
+    errors,
+)
 from .i18n import _
 from .setting import undefined, ConfigBag
 from .function import FUNCTION_WAITING_FOR_DICT, FUNCTION_WAITING_FOR_ERROR
@@ -149,11 +157,15 @@ class ParamDynOption(ParamOption):
         )
         if not isinstance(identifiers, list):
             raise Exception(
-                _("identifiers in ParamDynOption must be a list, not {0}").format(identifiers)
+                _("identifiers in ParamDynOption must be a list, not {0}").format(
+                    identifiers
+                )
             )
         if not isinstance(optional, bool):
             raise Exception(
-                _("optional in ParamDynOption must be a boolean, not {0}").format(optional)
+                _("optional in ParamDynOption must be a boolean, not {0}").format(
+                    optional
+                )
             )
         self.identifiers = identifiers
         self.optional = optional
@@ -204,7 +216,9 @@ class ParamInformation(Param):
 
     def set_option(self, option: "Option" = None) -> None:
         if not hasattr(self, "self_option"):
-            raise ConfigError(_("cannot add option in information after creating config"))
+            raise ConfigError(
+                _("cannot add option in information after creating config")
+            )
         if self.option:
             raise ConfigError(_("cannot redefine option in information"))
         if not option.impl_is_optiondescription():
@@ -464,7 +478,9 @@ def manager_callback(
                     ["configerror"],
                     config_bag.context.get_settings(),
                 )
-            errors.raise_carry_out_calculation_error(subconfig, _("unable to get value for calculating {0}, {1}"), err)
+            errors.raise_carry_out_calculation_error(
+                subconfig, _("unable to get value for calculating {0}, {1}"), err
+            )
         return value
 
     def get_option_bag(
@@ -496,7 +512,12 @@ def manager_callback(
             # raise PropertiesOptionError (which is catched) because must not add value None in carry_out_calculation
             if param.notraisepropertyerror or param.raisepropertyerror:
                 raise err from err
-            errors.raise_carry_out_calculation_error(subconfig, _("unable to carry out a calculation for {0}, {1}"), err, option=option)
+            errors.raise_carry_out_calculation_error(
+                subconfig,
+                _("unable to carry out a calculation for {0}, {1}"),
+                err,
+                option=option,
+            )
         except ValueError as err:
             display_name = option.impl_get_display_name(subconfig, with_quote=True)
             raise ValueError(
@@ -512,7 +533,12 @@ def manager_callback(
                     ["configerror"],
                     config_bag.context.get_settings(),
                 )
-            errors.raise_carry_out_calculation_error(subconfig, _("unable to get value for calculating {0}, {1}"), err, option=option)
+            errors.raise_carry_out_calculation_error(
+                subconfig,
+                _("unable to get value for calculating {0}, {1}"),
+                err,
+                option=option,
+            )
         return subsubconfig
 
     if isinstance(param, ParamValue):
@@ -532,7 +558,13 @@ def manager_callback(
                     search_name = search_option.impl_get_display_name(
                         None, with_quote=True
                     )
-                    errors.raise_carry_out_calculation_error(subconfig, _("cannot find information for {0}, {1} is a dynamic option"), None, option=option, extra_keys=[search_name])
+                    errors.raise_carry_out_calculation_error(
+                        subconfig,
+                        _("cannot find information for {0}, {1} is a dynamic option"),
+                        None,
+                        option=option,
+                        extra_keys=[search_name],
+                    )
             else:
                 isubconfig = get_option_bag(
                     config_bag,
@@ -551,7 +583,12 @@ def manager_callback(
                 param.default_value,
             )
         except ValueError as err:
-            errors.raise_carry_out_calculation_error(subconfig, _("unable to get value for calculating {0}, {1}"), err, option=option)
+            errors.raise_carry_out_calculation_error(
+                subconfig,
+                _("unable to get value for calculating {0}, {1}"),
+                err,
+                option=option,
+            )
 
     if isinstance(param, ParamIndex):
         return index
@@ -561,7 +598,14 @@ def manager_callback(
             not option.impl_is_optiondescription()
             or not option.impl_is_dynoptiondescription()
         ):
-            errors.raise_carry_out_calculation_error(subconfig, _("option {0} is not a dynoptiondescription or in a dynoptiondescription"), None, option=option)
+            errors.raise_carry_out_calculation_error(
+                subconfig,
+                _(
+                    "option {0} is not a dynoptiondescription or in a dynoptiondescription"
+                ),
+                None,
+                option=option,
+            )
         if subconfig.identifiers is None:
             # if uncalculated
             return
@@ -637,18 +681,36 @@ def manager_callback(
                                     )
                                 except AttributeError as err:
                                     if parent.path:
-                                        child_path = parent.path + '.' + name
+                                        child_path = parent.path + "." + name
                                     else:
                                         child_path = name
                                     if param.optional:
-                                        raise CancelParam(callbk_option.impl_getpath(), child_path)
+                                        raise CancelParam(
+                                            callbk_option.impl_getpath(), child_path
+                                        )
 
                                     identifiers = doption.get_identifiers(parent)
                                     if not identifiers:
-                                        errors.raise_carry_out_calculation_error(subconfig, _('cannot calculate arguments for {0}, {1} with identifier "{2}", there is no identifiers'), err, extra_keys=[identifier])
+                                        errors.raise_carry_out_calculation_error(
+                                            subconfig,
+                                            _(
+                                                'cannot calculate arguments for {0}, {1} with identifier "{2}", there is no identifiers'
+                                            ),
+                                            err,
+                                            extra_keys=[identifier],
+                                        )
                                     else:
-                                        identifiers_list = display_list(identifiers, add_quote=True)
-                                        errors.raise_carry_out_calculation_error(subconfig, _('cannot calculate arguments for {0}, {1} with identifier "{2}", list of valid identifiers: {3}'), err, extra_keys=[identifier, identifiers_list])
+                                        identifiers_list = display_list(
+                                            identifiers, add_quote=True
+                                        )
+                                        errors.raise_carry_out_calculation_error(
+                                            subconfig,
+                                            _(
+                                                'cannot calculate arguments for {0}, {1} with identifier "{2}", list of valid identifiers: {3}'
+                                            ),
+                                            err,
+                                            extra_keys=[identifier, identifiers_list],
+                                        )
                                 new_parents.append(
                                     parent.get_child(
                                         doption,
@@ -752,7 +814,12 @@ def carry_out_calculation(
         and option.impl_is_follower()
         and index is None
     ):
-        errors.raise_carry_out_calculation_error(subconfig, _("the follower {0} must have index in carry_out_calculation!"), None, option=option)
+        errors.raise_carry_out_calculation_error(
+            subconfig,
+            _("the follower {0} must have index in carry_out_calculation!"),
+            None,
+            option=option,
+        )
 
     def fake_items(iterator):
         return ((None, i) for i in iterator)
@@ -822,33 +889,14 @@ def carry_out_calculation(
         and option.impl_is_follower()
         and not option.impl_is_submulti()
     ):
-        if args or kwargs:
-            raise LeadershipError(
-                _(
-                    'the "{}" function with positional arguments "{}" '
-                    'and keyword arguments "{}" must not return '
-                    'a list ("{}") for the follower option {}'
-                    ""
-                ).format(
-                    callback.__name__,
-                    args,
-                    kwargs,
-                    ret,
-                    option.impl_get_display_name(subconfig, with_quote=True),
-                )
-            )
-        else:
-            raise LeadershipError(
-                _(
-                    'the "{}" function must not return a list ("{}") '
-                    "for the follower option {}"
-                    ""
-                ).format(
-                    callback.__name__,
-                    ret,
-                    option.impl_get_display_name(subconfig, with_quote=True),
-                )
-            )
+        raise LeadershipError(
+            subconfig,
+            "leadership-follower-callback-list",
+            callback=callback.__name__,
+            args=args,
+            kwargs=kwargs,
+            ret=ret,
+        )
     return ret
 
 
@@ -884,11 +932,14 @@ def calculate(
             'unexpected error "{1}" in function "{2}" with arguments "{3}" and "{4}" '
             "for option {0}"
         )
-        extra_keys = [callback.__name__,
-                      args,
-                      kwargs,
-                      ]
+        extra_keys = [
+            callback.__name__,
+            args,
+            kwargs,
+        ]
     else:
         msg = _('unexpected error "{1}" in function "{2}" for option {0}')
         extra_keys = [callback.__name__]
-    errors.raise_carry_out_calculation_error(subconfig, msg, error, extra_keys=extra_keys)
+    errors.raise_carry_out_calculation_error(
+        subconfig, msg, error, extra_keys=extra_keys
+    )
diff --git a/tiramisu/config.py b/tiramisu/config.py
index 54dbe56..219609b 100644
--- a/tiramisu/config.py
+++ b/tiramisu/config.py
@@ -228,7 +228,7 @@ class SubConfig:
         *,
         true_path: Optional[str] = None,
         # for python 3.9 properties: Union[list[str], undefined] = undefined,
-        properties = undefined,
+        properties=undefined,
         validate_properties: bool = True,
     ) -> None:
         self.index = index
@@ -417,13 +417,7 @@ class SubConfig:
             length = self.get_length_leadership()
             if index >= length:
                 raise LeadershipError(
-                    _(
-                        'index "{0}" is greater than the leadership length "{1}" for option {2}'
-                    ).format(
-                        index,
-                        length,
-                        option.impl_get_display_name(subsubconfig, with_quote=True),
-                    )
+                    subsubconfig, "leadership-greater", index=index, length=length
                 )
         return subsubconfig
 
@@ -869,9 +863,10 @@ class _Config(CCache):
                         subconfig, with_quote=True
                     )
                     raise LeadershipError(
-                        _(
-                            "the follower option {0} has greater length ({1}) than the leader length ({2})"
-                        ).format(option_name, follower_len, length)
+                        subconfig,
+                        "leadership-follower-greater",
+                        index=follower_len,
+                        length=length,
                     )
             self.get_settings().validate_mandatory(
                 subconfig,
diff --git a/tiramisu/error.py b/tiramisu/error.py
index 76c0933..3be49d1 100644
--- a/tiramisu/error.py
+++ b/tiramisu/error.py
@@ -18,6 +18,23 @@
 import weakref
 from .i18n import _
 
+from typing import Literal, Union
+
+
+TiramisuErrorCode = Literal[
+    "option-dynamic",
+    "option-not-found",
+    "property-frozen",
+    "property-error",
+    "property-mandatory",
+    "leadership-group_type",
+    "leadership-wrong_property",
+    "leadership-force_default_on_freeze",
+    "leadership-greater",
+    "leadership-follower-greater",
+    "leadership-follower-callback-list",
+]
+
 
 def display_list(
     lst,
@@ -69,6 +86,8 @@ class PropertiesOptionError(AttributeError):
         orig_opt=None,
         help_properties=None,
     ):
+        if orig_opt:
+            raise Exception("a la")
         if opt_type:
             self._opt_type = opt_type
             self._name = name
@@ -87,10 +106,23 @@ class PropertiesOptionError(AttributeError):
         self.help_properties = help_properties
         self._settings = settings
         self.msg = None
+        if not self.help_properties:
+            self.help_properties = self.proptype
+        properties = list(self.help_properties)
+        if properties == ["frozen"]:
+            self.code = "property-frozen"
+        elif properties == ["mandatory"]:
+            self.code = "property-mandatory"
+        else:
+            self.code = "property-error"
         super().__init__(None)
 
-    def set_orig_opt(self, opt):
-        self._orig_opt = opt
+    def display_properties(self, force_property=False, add_quote=True):
+        if force_property:
+            properties = self.proptype
+        else:
+            properties = self.help_properties
+        return display_list(list(properties), add_quote=add_quote)
 
     def __str__(self):
         # this part is a bit slow, so only execute when display
@@ -98,47 +130,81 @@ class PropertiesOptionError(AttributeError):
             return self.msg
         if self._settings is None:
             return "error"
-        if self.help_properties:
-            properties = list(self.help_properties)
-        else:
-            properties = list(self.proptype)
-        only_one = len(properties) == 1
-        properties_msg = display_list(properties, add_quote=True)
-        if only_one:
-            prop_msg = _("property")
-        else:
-            prop_msg = _("properties")
-        if properties == ["frozen"]:
-            if self._orig_opt:
-                msg = _('cannot modify the {0} {1} because "{2}" has {3} {4}')
-            else:
-                msg = _("cannot modify the {0} {1} because has {2} {3}")
-        elif properties == ["mandatory"]:
-            if self._orig_opt:
-                msg = _("cannot access to {0} {1} because \"{2}\" hasn't value")
-            else:
-                msg = _("{0} {1} is mandatory but hasn't value")
-        else:
-            if self._orig_opt:
-                msg = _('cannot access to {0} {1} because "{2}" has {3} {4}')
-            else:
-                msg = _("cannot access to {0} {1} because has {2} {3}")
+        arguments = [self._opt_type]
         if self._orig_opt:
-            # FIXME _orig_opt ?
-            self.msg = msg.format(
-                self._opt_type,
-                self._orig_opt.impl_get_display_name(subconfig, with_quote=True),
-                self._name,
-                prop_msg,
-                properties_msg,
+            arguments.append(
+                self._orig_opt.impl_get_display_name(subconfig, with_quote=True)
             )
+        arguments.append(self._name)
+        index = self._subconfig.index
+        if index is not None:
+            arguments.append(index)
+        if self.code == "property-frozen":
+            if index is not None:
+                if self._orig_opt:
+                    msg = _(
+                        'cannot modify the {0} {1} at index "{2}" because {3} is frozen'
+                    )
+                else:
+                    msg = _(
+                        'cannot modify the {0} {1} at index "{2}" because is frozen'
+                    )
+            else:
+                if self._orig_opt:
+                    msg = _("cannot modify the {0} {1} because {2} is frozen")
+                else:
+                    msg = _("cannot modify the {0} {1} because is frozen")
+        elif self.code == "property-mandatory":
+            if index is not None:
+                if self._orig_opt:
+                    msg = _(
+                        'cannot access to {0} {1} at index "{2}" because {2} hasn\'t value'
+                    )
+                else:
+                    msg = _('{0} {1} at index "{2}" is mandatory but hasn\'t value')
+            else:
+                if self._orig_opt:
+                    msg = _("cannot access to {0} {1} because {2} hasn't value")
+                else:
+                    msg = _("{0} {1} is mandatory but hasn't value")
         else:
-            self.msg = msg.format(self._opt_type, self._name, prop_msg, properties_msg)
+            if index is not None:
+                if self._orig_opt:
+                    msg = _(
+                        'cannot access to {0} {1} at index "{2}" because {3} has {4} {5}'
+                    )
+                else:
+                    msg = _(
+                        'cannot access to {0} {1} at index "{2}" because has {3} {4}'
+                    )
+            else:
+                if self._orig_opt:
+                    msg = _("cannot access to {0} {1} because {2} has {3} {4}")
+                else:
+                    msg = _("cannot access to {0} {1} because has {2} {3}")
+            only_one = len(self.help_properties) == 1
+            if only_one:
+                arguments.append(_("property"))
+            else:
+                arguments.append(_("properties"))
+            arguments.append(self.display_properties())
+        self.msg = msg.format(*arguments)
         del self._opt_type, self._name
         del self._settings, self._orig_opt
         return self.msg
 
 
+class AttributeOptionError(AttributeError):
+    def __init__(self, path: str, code: TiramisuErrorCode) -> None:
+        self.path = path
+        self.code = code
+
+    def __str__(self) -> str:
+        if self.code == "option-dynamic":
+            return _('cannot access to "{0}" it\'s a dynamic option').format(self.path)
+        return _('"{0}" is not an option').format(self.path)
+
+
 # ____________________________________________________________
 # Exceptions for a Config
 class ConfigError(Exception):
@@ -163,8 +229,74 @@ class ConflictError(Exception):
 # ____________________________________________________________
 # miscellaneous exceptions
 class LeadershipError(Exception):
-    "problem with a leadership's value length"
-    pass
+    def __init__(
+        self,
+        subconfig: Union[str, "SubConfig"],
+        code,
+        *,
+        prop=None,
+        index=None,
+        length=None,
+        callback=None,
+        args=None,
+        kwargs=None,
+        ret=None,
+    ):
+        if isinstance(subconfig, str):
+            self.path = self.display_name = subconfig
+        else:
+            self.path = subconfig.path
+            option = subconfig.option
+            self.display_name = option.impl_get_display_name(subconfig, with_quote=True)
+        self.code = code
+        if prop:
+            self.prop = prop
+        if index:
+            self.index = index
+        if length:
+            self.length = length
+        if callback:
+            self.callback = callback
+        if args:
+            self.args = args
+        if kwargs:
+            self.kwargs = kwargs
+        if ret:
+            self.ret = ret
+
+    def __str__(self):
+        if self.code == "leadership-group_type":
+            return _('cannot set "group_type" attribute for the Leadership {0}').format(
+                self.display_name
+            )
+        if self.code == "leadership-wrong_property":
+            return _('the leader {0} cannot have "{1}" property').format(
+                self.display_name, self.prop
+            )
+        if self.code == "leadership-force_default_on_freeze":
+            return _(
+                'the leader {0} cannot have "force_default_on_freeze" or "force_metaconfig_on_freeze" property without "frozen"'
+            ).format(self.display_name)
+        if self.code == "leadership-reduce":
+            return _("cannot reduce length of the leader {0}").format(self.display_name)
+        if self.code == "leadership-greater":
+            return _(
+                'index "{0}" is greater than the leadership length "{1}" for option {2}'
+            ).format(self.index, self.length, self.display_name)
+        if self.code == "leadership-follower-greater":
+            return _(
+                "the follower option {0} has greater length ({1}) than the leader length ({2})"
+            ).format(self.display_name, self.index, self.length)
+        if self.code == "leadership-follower-callback-list":
+            if self.args or self.kwargs:
+                return _(
+                    'the "{0}" function with positional arguments "{1}" and keyword arguments "{2}" must not return a list ("{3}") for the follower option {4}'
+                ).format(
+                    self.callback, self.args, self.kwargs, self.ret, self.display_name
+                )
+            return _(
+                'the "{0}" function must not return a list ("{1}") for the follower option {2}'
+            ).format(self.callback, self.ret, self.display_name)
 
 
 class ConstError(TypeError):
@@ -186,7 +318,9 @@ class _CommonError:
         try:
             msg = self.prefix
         except AttributeError:
-            self.prefix = self.tmpl.format(self.val, _(self.display_type), self.name, self.index)
+            self.prefix = self.tmpl.format(
+                self.val, _(self.display_type), self.name, self.index
+            )
             msg = self.prefix
         if self.err_msg:
             if msg:
@@ -203,12 +337,16 @@ class ValueWarning(_CommonError, UserWarning):
 
     def __init__(self, **kwargs):
         if ValueWarning.tmpl is None:
-            if kwargs.get('index') is None:
-                ValueWarning.tmpl = _('attention, "{0}" could be an invalid {1} for {2}')
+            if kwargs.get("index") is None:
+                ValueWarning.tmpl = _(
+                    'attention, "{0}" could be an invalid {1} for {2}'
+                )
             else:
-                ValueWarning.tmpl = _('attention, "{0}" could be an invalid {1} for {2} at index "{3}"')
-        if list(kwargs) == ['msg']:
-            self.msg = kwargs['msg']
+                ValueWarning.tmpl = _(
+                    'attention, "{0}" could be an invalid {1} for {2} at index "{3}"'
+                )
+        if list(kwargs) == ["msg"]:
+            self.msg = kwargs["msg"]
         else:
             super().__init__(**kwargs)
             self.msg = None
@@ -224,7 +362,7 @@ class ValueOptionError(_CommonError, ValueError):
 
     def __init__(self, **kwargs):
         if ValueOptionError.tmpl is None:
-            if kwargs.get('index') is None:
+            if kwargs.get("index") is None:
                 self.tmpl = _('"{0}" is an invalid {1} for {2}')
             else:
                 self.tmpl = _('"{0}" is an invalid {1} for {2} at index "{3}"')
@@ -258,12 +396,12 @@ class CancelParam(Exception):
 
 class Errors:
     @staticmethod
-    def raise_carry_out_calculation_error(subconfig, message, original_error, option=None, extra_keys=[]):
+    def raise_carry_out_calculation_error(
+        subconfig, message, original_error, option=None, extra_keys=[]
+    ):
         if option is None:
             option = subconfig.option
-        display_name = option.impl_get_display_name(
-            subconfig, with_quote=True
-        )
+        display_name = option.impl_get_display_name(subconfig, with_quote=True)
         if original_error:
             raise ConfigError(
                 message.format(display_name, original_error, *extra_keys)
diff --git a/tiramisu/option/domainnameoption.py b/tiramisu/option/domainnameoption.py
index b08895b..1c25df0 100644
--- a/tiramisu/option/domainnameoption.py
+++ b/tiramisu/option/domainnameoption.py
@@ -176,9 +176,7 @@ class DomainnameOption(StrOption):
             try:
                 socket.gethostbyname(value)
             except socket.gaierror as err:
-                raise ValueError(
-                    _("DNS resolution failed").format(value)
-                ) from err
+                raise ValueError(_("DNS resolution failed").format(value)) from err
             except Exception as err:
                 raise ValueError(
                     _("error resolving DNS: {1}").format(value, err)
diff --git a/tiramisu/option/filenameoption.py b/tiramisu/option/filenameoption.py
index ac9189a..5db0875 100644
--- a/tiramisu/option/filenameoption.py
+++ b/tiramisu/option/filenameoption.py
@@ -74,9 +74,12 @@ class FilenameOption(StrOption):
             if not found and "directory" in types and file.is_dir():
                 found = True
             if not found:
-                translated_types = [{"file": _("file"), "directory": _("directory")}.get(typ) for typ in types]
+                translated_types = [
+                    {"file": _("file"), "directory": _("directory")}.get(typ)
+                    for typ in types
+                ]
                 raise ValueError(
-                    _('cannot find this {0}').format(
+                    _("cannot find this {0}").format(
                         display_list(translated_types, separator="or"), value
                     )
                 )
diff --git a/tiramisu/option/intoption.py b/tiramisu/option/intoption.py
index 5c8a4fc..514e11d 100644
--- a/tiramisu/option/intoption.py
+++ b/tiramisu/option/intoption.py
@@ -43,7 +43,7 @@ class IntOption(Option):
         value: int,
     ) -> None:
         if not isinstance(value, int):
-            raise ValueError(_('which is not an integer'))
+            raise ValueError(_("which is not an integer"))
 
     def second_level_validation(self, value, warnings_only):
         min_number = self.impl_get_extra("min_number")
diff --git a/tiramisu/option/leadership.py b/tiramisu/option/leadership.py
index 829eb3f..1a4b11e 100644
--- a/tiramisu/option/leadership.py
+++ b/tiramisu/option/leadership.py
@@ -51,9 +51,7 @@ class Leadership(OptionDescription):
         **kwargs,
     ) -> None:
         if "group_type" in kwargs:
-            raise LeadershipError(
-                _('cannot set "group_type" attribute for a Leadership')
-            )
+            raise LeadershipError(name, "leadership-group_type")
         super().__init__(
             name,
             doc,
@@ -85,9 +83,7 @@ class Leadership(OptionDescription):
                 if prop not in ALLOWED_LEADER_PROPERTIES and not isinstance(
                     prop, Calculation
                 ):
-                    raise LeadershipError(
-                        _('leader cannot have "{}" property').format(prop)
-                    )
+                    raise LeadershipError(name, "leadership-wrong_property", prop=prop)
 
     def _check_child_is_valid(
         self,
diff --git a/tiramisu/option/option.py b/tiramisu/option/option.py
index b8e9b75..e7ed6e1 100644
--- a/tiramisu/option/option.py
+++ b/tiramisu/option/option.py
@@ -259,7 +259,7 @@ class Option(BaseOption):
         *,
         check_error: bool = True,
         loaded: bool = False,
-        self_properties: frozenset=frozenset(),
+        self_properties: frozenset = frozenset(),
     ) -> bool:
         """Return True if value is really valid
         If not validate or invalid return it returns False
@@ -269,8 +269,11 @@ class Option(BaseOption):
                 config_properties = subconfig.config_bag.properties
                 self_properties = subconfig.properties
             else:
-                config_properties = {'validator'}
-            if "validator" not in config_properties or "validator" not in self_properties:
+                config_properties = {"validator"}
+            if (
+                "validator" not in config_properties
+                or "validator" not in self_properties
+            ):
                 return False
         if subconfig:
             force_index = subconfig.index
@@ -443,11 +446,21 @@ class Option(BaseOption):
                 or "demoting_error_warning" not in subconfig.config_bag.properties
             ):
                 raise ValueOptionError(
-                    subconfig=subconfig, val=val, display_type=_(self.get_type()), opt=self, err_msg=str(err), index=err_index
+                    subconfig=subconfig,
+                    val=val,
+                    display_type=_(self.get_type()),
+                    opt=self,
+                    err_msg=str(err),
+                    index=err_index,
                 ) from err
             warnings.warn_explicit(
                 ValueErrorWarning(
-                    subconfig=subconfig, val=val, display_type=_(self.get_type()), opt=self, err_msg=str(err), index=err_index
+                    subconfig=subconfig,
+                    val=val,
+                    display_type=_(self.get_type()),
+                    opt=self,
+                    err_msg=str(err),
+                    index=err_index,
                 ),
                 ValueErrorWarning,
                 self.__class__.__name__,
diff --git a/tiramisu/option/optiondescription.py b/tiramisu/option/optiondescription.py
index c086050..b67c5e2 100644
--- a/tiramisu/option/optiondescription.py
+++ b/tiramisu/option/optiondescription.py
@@ -29,7 +29,7 @@ from ..setting import ConfigBag, groups, undefined, owners, Undefined
 from .baseoption import BaseOption
 
 # from .syndynoption import SubDynOptionDescription, SynDynOptionDescription
-from ..error import ConfigError, ConflictError
+from ..error import ConfigError, ConflictError, AttributeOptionError
 
 
 class CacheOptionDescription(BaseOption):
@@ -242,12 +242,10 @@ class OptionDescriptionWalk(CacheOptionDescription):
             ]  # pylint: disable=no-member
             if option.impl_is_dynoptiondescription() and not allow_dynoption:
                 if parent.path:
-                    path = parent.path + '.' + name
+                    path = parent.path + "." + name
                 else:
                     path = name
-                raise AttributeError(
-                    _('cannot access to "{0}" it\'s a dynamic option').format(path)
-                )
+                raise AttributeOptionError(path, "option-dynamic")
             return option
 
     def get_child(
@@ -279,14 +277,10 @@ class OptionDescriptionWalk(CacheOptionDescription):
                     return child
                 return identifier, child
         if parent.path is None:
-            raise AttributeError(
-                _('cannot find "{0}"').format(name)
-            )
-        raise AttributeError(
-            _('cannot find "{0}" in "{1}"').format(
-                name, parent.path
-            )
-        )
+            path = name
+        else:
+            path = parent.path + "." + name
+        raise AttributeOptionError(path, "option-not-found")
 
     def get_children(self) -> List[BaseOption]:
         """get children"""
diff --git a/tiramisu/option/stroption.py b/tiramisu/option/stroption.py
index b8a9a22..ce68bcc 100644
--- a/tiramisu/option/stroption.py
+++ b/tiramisu/option/stroption.py
@@ -38,7 +38,7 @@ class StrOption(Option):
     ) -> None:
         """validation"""
         if not isinstance(value, str):
-            raise ValueError(_('which is not a string'))
+            raise ValueError(_("which is not a string"))
 
 
 class RegexpOption(StrOption):
diff --git a/tiramisu/option/urloption.py b/tiramisu/option/urloption.py
index 41636af..f8ad82a 100644
--- a/tiramisu/option/urloption.py
+++ b/tiramisu/option/urloption.py
@@ -56,23 +56,23 @@ class URLOption(StrOption):
         # pylint: disable=too-many-arguments,too-many-locals,redefined-builtin
         extra = {}
         extra["_domainname"] = DomainnameOption(
-                name,
-                doc,
-                allow_ip=allow_ip,
-                type=type,
-                allow_without_dot=allow_without_dot,
-                _extra=extra,
-            )
-        extra["_port"] =  PortOption(
-                name,
-                doc,
-                allow_range=allow_range,
-                allow_zero=allow_zero,
-                allow_wellknown=allow_wellknown,
-                allow_registred=allow_registred,
-                allow_private=allow_private,
-                _extra=extra,
-            )
+            name,
+            doc,
+            allow_ip=allow_ip,
+            type=type,
+            allow_without_dot=allow_without_dot,
+            _extra=extra,
+        )
+        extra["_port"] = PortOption(
+            name,
+            doc,
+            allow_range=allow_range,
+            allow_zero=allow_zero,
+            allow_wellknown=allow_wellknown,
+            allow_registred=allow_registred,
+            allow_private=allow_private,
+            _extra=extra,
+        )
         super().__init__(
             name,
             doc,
diff --git a/tiramisu/setting.py b/tiramisu/setting.py
index d69a3a1..1c163b8 100644
--- a/tiramisu/setting.py
+++ b/tiramisu/setting.py
@@ -476,7 +476,7 @@ class Settings:
                         and new_prop not in ALLOWED_LEADER_PROPERTIES
                     ):
                         raise LeadershipError(
-                            _('leader cannot have "{new_prop}" property')
+                            subconfig, "leadership-wrong_property", prop=new_prop
                         )
                     props.add(new_prop)
             props -= self.getpermissives(subconfig)
@@ -564,19 +564,15 @@ class Settings:
             not_allowed_properties = properties - ALLOWED_LEADER_PROPERTIES
             if not_allowed_properties:
                 raise LeadershipError(
-                    _('leader cannot have "{0}" property').format(
-                        display_list(not_allowed_properties)
-                    )
+                    subconfig,
+                    "leadership-wrong_property",
+                    prop=display_list(not_allowed_properties),
                 )
             if (
                 "force_default_on_freeze" in properties
                 or "force_metaconfig_on_freeze" in properties
             ) and "frozen" not in properties:
-                raise LeadershipError(
-                    _(
-                        'a leader ({0}) cannot have "force_default_on_freeze" or "force_metaconfig_on_freeze" property without "frozen"'
-                    ).format(opt.impl_get_display_name())
-                )
+                raise LeadershipError(subconfig, "leadership-force_default_on_freeze")
         self._properties.setdefault(subconfig.path, {})[subconfig.index] = properties
         # values too because of follower values could have a PropertiesOptionError has value
         subconfig.config_bag.context.reset_cache(subconfig)
diff --git a/tiramisu/value.py b/tiramisu/value.py
index 26cc612..9ded876 100644
--- a/tiramisu/value.py
+++ b/tiramisu/value.py
@@ -295,9 +295,9 @@ class Values:
                 owners.forced,
             )
         validator = (
-            "validator" in setting_properties and
-            "validator" in self_properties and
-            "demoting_error_warning" not in setting_properties
+            "validator" in setting_properties
+            and "validator" in self_properties
+            and "demoting_error_warning" not in setting_properties
         )
         if validator and not has_calculation:
             cache = subconfig.config_bag.context.get_values_cache()
@@ -306,7 +306,11 @@ class Values:
                 value,
                 validated=validator,
             )
-        elif "validator" in setting_properties and "validator" in self_properties and has_calculation:
+        elif (
+            "validator" in setting_properties
+            and "validator" in self_properties
+            and has_calculation
+        ):
             cache = subconfig.config_bag.context.get_values_cache()
             cache.delcache(subconfig.path)
 
@@ -592,7 +596,12 @@ class Values:
         self_properties = subconfig.properties
         context = config_bag.context
         setting_properties = config_bag.properties
-        if validate and hasvalue and "validator" in setting_properties and "validator" in self_properties:
+        if (
+            validate
+            and hasvalue
+            and "validator" in setting_properties
+            and "validator" in self_properties
+        ):
             fake_context = context.gen_fake_context()
             fake_config_bag = config_bag.copy()
             fake_config_bag.remove_validation()