diff --git a/src/dify_plugin/entities/model/provider.py b/src/dify_plugin/entities/model/provider.py
index 1ae3ee39..d465ffef 100644
--- a/src/dify_plugin/entities/model/provider.py
+++ b/src/dify_plugin/entities/model/provider.py
@@ -65,10 +65,13 @@ class FormOption(BaseModel):
     value: str
     show_on: list[FormShowOnObject] = Field(default_factory=list)
 
-    def __init__(self, **data: object) -> None:
-        super().__init__(**data)
-        if not self.label:
-            self.label = I18nObject(en_us=self.value)
+    @model_validator(mode="before")
+    @classmethod
+    def validate_label(cls, data: dict) -> dict:
+        if isinstance(data, dict) and not data.get("label") and "value" in data:
+            data["label"] = I18nObject(en_US=str(data["value"]))
+
+        return data
 
 
 @docs(
diff --git a/src/dify_plugin/entities/model/schema.py b/src/dify_plugin/entities/model/schema.py
index a5b6ce47..4a920cf2 100644
--- a/src/dify_plugin/entities/model/schema.py
+++ b/src/dify_plugin/entities/model/schema.py
@@ -304,7 +304,7 @@ class ProviderModel(BaseModel):
     @classmethod
     def validate_label(cls, data: dict) -> dict:
         if isinstance(data, dict) and not data.get("label"):
-            data["label"] = I18nObject(en_us=data["model"])
+            data["label"] = I18nObject(en_US=data["model"])
 
         return data
 
@@ -369,7 +369,7 @@ def validate_label(cls, data: dict) -> dict:
                     pass
 
             if not data.get("label"):
-                data["label"] = I18nObject(en_us=data["name"])
+                data["label"] = I18nObject(en_US=data["name"])
 
         return data
 
diff --git a/src/dify_plugin/entities/parameters.py b/src/dify_plugin/entities/parameters.py
index 5e1e7006..79253ba5 100644
--- a/src/dify_plugin/entities/parameters.py
+++ b/src/dify_plugin/entities/parameters.py
@@ -17,27 +17,27 @@ class I18nObject(BaseModel):
         validate_by_name=True,
     )
 
-    zh_hans: str | None = Field(default=None, alias="zh_Hans")
-    pt_br: str | None = Field(default=None, alias="pt_BR")
-    ja_jp: str | None = Field(default=None, alias="ja_JP")
-    en_us: str = Field(alias="en_US")
+    zh_Hans: str | None = Field(default=None)  # noqa: N815
+    pt_BR: str | None = Field(default=None)  # noqa: N815
+    ja_JP: str | None = Field(default=None)  # noqa: N815
+    en_US: str  # noqa: N815
 
     @model_validator(mode="after")
     def fill_missing_translations(self) -> "I18nObject":
-        if not self.zh_hans:
-            self.zh_hans = self.en_us
-        if not self.pt_br:
-            self.pt_br = self.en_us
-        if not self.ja_jp:
-            self.ja_jp = self.en_us
+        if not self.zh_Hans:
+            self.zh_Hans = self.en_US
+        if not self.pt_BR:
+            self.pt_BR = self.en_US
+        if not self.ja_JP:
+            self.ja_JP = self.en_US
         return self
 
     def to_dict(self) -> dict:
         return {
-            "zh_Hans": self.zh_hans,
-            "en_US": self.en_us,
-            "pt_BR": self.pt_br,
-            "ja_JP": self.ja_jp,
+            "zh_Hans": self.zh_Hans,
+            "en_US": self.en_US,
+            "pt_BR": self.pt_BR,
+            "ja_JP": self.ja_JP,
         }
 
 
diff --git a/src/dify_plugin/interfaces/model/ai_model.py b/src/dify_plugin/interfaces/model/ai_model.py
index 663ea132..332d0393 100644
--- a/src/dify_plugin/interfaces/model/ai_model.py
+++ b/src/dify_plugin/interfaces/model/ai_model.py
@@ -292,28 +292,28 @@ def _get_customizable_model_schema(
                         parameter_rule.required = default_parameter_rule["required"]
                     if not parameter_rule.help and "help" in default_parameter_rule:
                         parameter_rule.help = I18nObject(
-                            en_us=default_parameter_rule["help"]["en_US"],
+                            en_US=default_parameter_rule["help"]["en_US"],
                         )
                     if (
                         parameter_rule.help
-                        and not parameter_rule.help.en_us
+                        and not parameter_rule.help.en_US
                         and (
                             "help" in default_parameter_rule
                             and "en_US" in default_parameter_rule["help"]
                         )
                     ):
-                        parameter_rule.help.en_us = default_parameter_rule["help"][
+                        parameter_rule.help.en_US = default_parameter_rule["help"][
                             "en_US"
                         ]
                     if (
                         parameter_rule.help
-                        and not parameter_rule.help.zh_hans
+                        and not parameter_rule.help.zh_Hans
                         and (
                             "help" in default_parameter_rule
                             and "zh_Hans" in default_parameter_rule["help"]
                         )
                     ):
-                        parameter_rule.help.zh_hans = default_parameter_rule[
+                        parameter_rule.help.zh_Hans = default_parameter_rule[
                             "help"
                         ].get("zh_Hans", default_parameter_rule["help"]["en_US"])
                 except ValueError:
diff --git a/src/dify_plugin/interfaces/model/openai_compatible/llm.py b/src/dify_plugin/interfaces/model/openai_compatible/llm.py
index 0d811811..ce05dfb1 100644
--- a/src/dify_plugin/interfaces/model/openai_compatible/llm.py
+++ b/src/dify_plugin/interfaces/model/openai_compatible/llm.py
@@ -363,7 +363,7 @@ def get_customizable_model_schema(
 
         entity = AIModelEntity(
             model=model,
-            label=I18nObject(en_us=model),
+            label=I18nObject(en_US=model),
             model_type=ModelType.LLM,
             fetch_from=FetchFrom.CUSTOMIZABLE_MODEL,
             features=features,
@@ -376,16 +376,16 @@ def get_customizable_model_schema(
             parameter_rules=[
                 ParameterRule(
                     name=DefaultParameterName.TEMPERATURE.value,
-                    label=I18nObject(en_us="Temperature", zh_hans="温度"),
+                    label=I18nObject(en_US="Temperature", zh_Hans="温度"),
                     help=I18nObject(
-                        en_us=(
+                        en_US=(
                             "Kernel sampling threshold. Used to determine the "
                             "randomness of the results."
                             "The higher the value, the stronger the randomness."
                             "The higher the possibility of getting different "
                             "answers to the same question."
                         ),
-                        zh_hans=(
+                        zh_Hans=(
                             "核采样阈值。用于决定结果随机性，取值越高随机性越强即"
                             "相同的问题得到的不同答案的可能性越高。"
                         ),
@@ -398,9 +398,9 @@ def get_customizable_model_schema(
                 ),
                 ParameterRule(
                     name=DefaultParameterName.TOP_P.value,
-                    label=I18nObject(en_us="Top P", zh_hans="Top P"),
+                    label=I18nObject(en_US="Top P", zh_Hans="Top P"),
                     help=I18nObject(
-                        en_us=(
+                        en_US=(
                             "The probability threshold of the nucleus sampling "
                             "method during the generation process."
                             "The larger the value is, the higher the randomness "
@@ -408,7 +408,7 @@ def get_customizable_model_schema(
                             "The smaller the value is, the higher the certainty "
                             "of generation will be."
                         ),
-                        zh_hans=(
+                        zh_Hans=(
                             "生成过程中核采样方法概率阈值。取值越大，生成的随机性"
                             "越高；取值越小，生成的确定性越高。"
                         ),
@@ -421,15 +421,15 @@ def get_customizable_model_schema(
                 ),
                 ParameterRule(
                     name=DefaultParameterName.FREQUENCY_PENALTY.value,
-                    label=I18nObject(en_us="Frequency Penalty", zh_hans="频率惩罚"),
+                    label=I18nObject(en_US="Frequency Penalty", zh_Hans="频率惩罚"),
                     help=I18nObject(
-                        en_us=(
+                        en_US=(
                             "For controlling the repetition rate of words used "
                             "by the model."
                             "Increasing this can reduce the repetition of the "
                             "same words in the model's output."
                         ),
-                        zh_hans=(
+                        zh_Hans=(
                             "用于控制模型已使用字词的重复率。 提高此项可以降低模型在"
                             "输出中重复相同字词的重复度。"
                         ),
@@ -441,15 +441,15 @@ def get_customizable_model_schema(
                 ),
                 ParameterRule(
                     name=DefaultParameterName.PRESENCE_PENALTY.value,
-                    label=I18nObject(en_us="Presence Penalty", zh_hans="存在惩罚"),
+                    label=I18nObject(en_US="Presence Penalty", zh_Hans="存在惩罚"),
                     help=I18nObject(
-                        en_us=(
+                        en_US=(
                             "Used to control the repetition rate when "
                             "generating models."
                             "Increasing this can reduce the repetition rate "
                             "of model generation."
                         ),
-                        zh_hans="用于控制模型生成时的重复度。提高此项可以降低模型生成的重复度。",
+                        zh_Hans="用于控制模型生成时的重复度。提高此项可以降低模型生成的重复度。",
                     ),
                     type=ParameterType.FLOAT,
                     default=float(credentials.get("presence_penalty", 0)),
@@ -458,10 +458,10 @@ def get_customizable_model_schema(
                 ),
                 ParameterRule(
                     name=DefaultParameterName.MAX_TOKENS.value,
-                    label=I18nObject(en_us="Max Tokens", zh_hans="最大标记"),
+                    label=I18nObject(en_US="Max Tokens", zh_Hans="最大标记"),
                     help=I18nObject(
-                        en_us="Maximum length of tokens for the model response.",
-                        zh_hans="模型回答的tokens的最大长度。",
+                        en_US="Maximum length of tokens for the model response.",
+                        zh_Hans="模型回答的tokens的最大长度。",
                     ),
                     type=ParameterType.INT,
                     default=512,
diff --git a/src/dify_plugin/interfaces/model/openai_compatible/rerank.py b/src/dify_plugin/interfaces/model/openai_compatible/rerank.py
index 40ae8e73..76ad1b59 100644
--- a/src/dify_plugin/interfaces/model/openai_compatible/rerank.py
+++ b/src/dify_plugin/interfaces/model/openai_compatible/rerank.py
@@ -176,7 +176,7 @@ def get_customizable_model_schema(
         del credentials
         return AIModelEntity(
             model=model,
-            label=I18nObject(en_us=model),
+            label=I18nObject(en_US=model),
             model_type=ModelType.RERANK,
             fetch_from=FetchFrom.CUSTOMIZABLE_MODEL,
             model_properties={},
diff --git a/src/dify_plugin/interfaces/model/openai_compatible/text_embedding.py b/src/dify_plugin/interfaces/model/openai_compatible/text_embedding.py
index 21b2e046..032c9b97 100644
--- a/src/dify_plugin/interfaces/model/openai_compatible/text_embedding.py
+++ b/src/dify_plugin/interfaces/model/openai_compatible/text_embedding.py
@@ -217,7 +217,7 @@ def get_customizable_model_schema(
         """
         return AIModelEntity(
             model=model,
-            label=I18nObject(en_us=model),
+            label=I18nObject(en_US=model),
             model_type=ModelType.TEXT_EMBEDDING,
             fetch_from=FetchFrom.CUSTOMIZABLE_MODEL,
             model_properties={
diff --git a/src/dify_plugin/interfaces/model/openai_compatible/tts.py b/src/dify_plugin/interfaces/model/openai_compatible/tts.py
index b61608c1..eed873bf 100644
--- a/src/dify_plugin/interfaces/model/openai_compatible/tts.py
+++ b/src/dify_plugin/interfaces/model/openai_compatible/tts.py
@@ -152,7 +152,7 @@ def get_customizable_model_schema(
 
         return AIModelEntity(
             model=model,
-            label=I18nObject(en_us=model),
+            label=I18nObject(en_US=model),
             fetch_from=FetchFrom.CUSTOMIZABLE_MODEL,
             model_type=ModelType.TTS,
             model_properties={
diff --git a/tests/entities/models/test_provider.py b/tests/entities/models/test_provider.py
new file mode 100644
index 00000000..042d2a37
--- /dev/null
+++ b/tests/entities/models/test_provider.py
@@ -0,0 +1,9 @@
+from dify_plugin.entities.model.provider import FormOption
+
+
+def test_form_option_uses_value_as_default_label() -> None:
+    option = FormOption(value="gpt-4")
+
+    assert option.label.en_US == "gpt-4"
+    assert option.label.zh_Hans == "gpt-4"
+    assert option.value == "gpt-4"
diff --git a/tests/entities/test_parameters.py b/tests/entities/test_parameters.py
new file mode 100644
index 00000000..7c940d76
--- /dev/null
+++ b/tests/entities/test_parameters.py
@@ -0,0 +1,48 @@
+import pytest
+from pydantic import ValidationError
+
+from dify_plugin.entities import I18nObject
+
+
+def test_i18n_object_uses_legacy_python_attribute_names() -> None:
+    i18n = I18nObject.model_validate({
+        "en_US": "English",
+        "zh_Hans": "简体中文",
+        "pt_BR": "Português",
+        "ja_JP": "日本語",
+    })
+
+    assert i18n.en_US == "English"
+    assert i18n.zh_Hans == "简体中文"
+    assert i18n.pt_BR == "Português"
+    assert i18n.ja_JP == "日本語"
+    assert i18n.model_dump() == {
+        "en_US": "English",
+        "zh_Hans": "简体中文",
+        "pt_BR": "Português",
+        "ja_JP": "日本語",
+    }
+
+
+def test_i18n_object_fills_missing_translations_from_english() -> None:
+    i18n = I18nObject(en_US="English")
+
+    assert i18n.en_US == "English"
+    assert i18n.zh_Hans == "English"
+    assert i18n.pt_BR == "English"
+    assert i18n.ja_JP == "English"
+
+    assert i18n.to_dict() == {
+        "en_US": "English",
+        "zh_Hans": "English",
+        "pt_BR": "English",
+        "ja_JP": "English",
+    }
+
+
+def test_i18n_object_does_not_accept_new_python_attribute_names() -> None:
+    with pytest.raises(AttributeError):
+        _ = I18nObject(en_US="English").en_us
+
+    with pytest.raises(ValidationError):
+        I18nObject(en_us="English")
diff --git a/tests/interfaces/model/test_construct_model_provider.py b/tests/interfaces/model/test_construct_model_provider.py
index 943d2c61..810dde27 100644
--- a/tests/interfaces/model/test_construct_model_provider.py
+++ b/tests/interfaces/model/test_construct_model_provider.py
@@ -19,7 +19,7 @@ def validate_provider_credentials(self, credentials: dict) -> None:
 
     provider_schema = ProviderEntity(
         provider="test",
-        label=I18nObject(en_us="test"),
+        label=I18nObject(en_US="test"),
         supported_model_types=[ModelType.LLM],
         configurate_methods=[],
     )
diff --git a/tests/interfaces/model/test_model_registry_get_model.py b/tests/interfaces/model/test_model_registry_get_model.py
index 4b2aef36..58e716ca 100644
--- a/tests/interfaces/model/test_model_registry_get_model.py
+++ b/tests/interfaces/model/test_model_registry_get_model.py
@@ -42,7 +42,7 @@ def test_model_provider_get_model_instance_delegates_to_factory() -> None:
 
     provider_schema = ProviderEntity(
         provider="test",
-        label=I18nObject(en_us="test"),
+        label=I18nObject(en_US="test"),
         supported_model_types=[ModelType.LLM],
         configurate_methods=[],
     )
@@ -60,7 +60,7 @@ def test_model_provider_get_model_instance_get_multiple_instances() -> None:
     provider = MockModelProvider(
         provider_schemas=ProviderEntity(
             provider="test",
-            label=I18nObject(en_us="test"),
+            label=I18nObject(en_US="test"),
             supported_model_types=[ModelType.LLM],
             configurate_methods=[],
         ),
diff --git a/tests/interfaces/model/utils.py b/tests/interfaces/model/utils.py
index d4f191f8..3f42e743 100644
--- a/tests/interfaces/model/utils.py
+++ b/tests/interfaces/model/utils.py
@@ -14,7 +14,7 @@ def prepare_model_factory(models: Mapping[ModelType, type[AIModel]]) -> ModelFac
     return ModelFactory(
         ModelProviderConfiguration(
             provider="test",
-            label=I18nObject(en_us="test"),
+            label=I18nObject(en_US="test"),
             supported_model_types=list(models.keys()),
             configurate_methods=[],
             extra=ModelProviderConfigurationExtra(
diff --git a/tests/interfaces/tool/test_costruct_tool.py b/tests/interfaces/tool/test_costruct_tool.py
index 28b2621e..fd623d62 100644
--- a/tests/interfaces/tool/test_costruct_tool.py
+++ b/tests/interfaces/tool/test_costruct_tool.py
@@ -81,7 +81,7 @@ def _invoke(
 
         def _fetch_parameter_options(self, parameter: str) -> list[ParameterOption]:
             del parameter
-            return [ParameterOption(value="test", label=I18nObject(en_us="test"))]
+            return [ParameterOption(value="test", label=I18nObject(en_US="test"))]
 
     session = Session(
         session_id="test",
@@ -95,5 +95,5 @@ def _fetch_parameter_options(self, parameter: str) -> list[ParameterOption]:
         session=session,
     )
     assert tool.fetch_parameter_options("test") == [
-        ParameterOption(value="test", label=I18nObject(en_us="test"))
+        ParameterOption(value="test", label=I18nObject(en_US="test"))
     ]
diff --git a/tests/test_model_polling.py b/tests/test_model_polling.py
index 67abc58c..788c7481 100644
--- a/tests/test_model_polling.py
+++ b/tests/test_model_polling.py
@@ -70,7 +70,7 @@ def prompt_messages(self) -> list[UserPromptMessage]:
     def model_entity(self) -> AIModelEntity:
         return AIModelEntity(
             model=self.model,
-            label=I18nObject(en_us=self.model),
+            label=I18nObject(en_US=self.model),
             model_type=ModelType.LLM,
             features=[ModelFeature.POLLING],
             fetch_from=FetchFrom.PREDEFINED_MODEL,
diff --git a/tests/test_model_registry_get_model.py b/tests/test_model_registry_get_model.py
index 111a167b..cee177e4 100644
--- a/tests/test_model_registry_get_model.py
+++ b/tests/test_model_registry_get_model.py
@@ -147,7 +147,7 @@ def mock_resolve_plugin_cls(self: PluginRegistration) -> None:
         # add MockLLM to models_mapping
         provider_configuration = ModelProviderConfiguration(
             provider="test",
-            label=I18nObject(zh_hans="test", en_us="test"),
+            label=I18nObject(zh_Hans="test", en_US="test"),
             models={},
             supported_model_types=[ModelType.LLM],
             extra=ModelProviderConfigurationExtra(
@@ -165,7 +165,7 @@ def mock_resolve_plugin_cls(self: PluginRegistration) -> None:
                 MockModelProvider(
                     provider_schemas=ProviderEntity(
                         provider="test",
-                        label=I18nObject(zh_hans="test", en_us="test"),
+                        label=I18nObject(zh_Hans="test", en_US="test"),
                         supported_model_types=[ModelType.LLM],
                         configurate_methods=[],
                     ),
diff --git a/tests/test_trigger_factory.py b/tests/test_trigger_factory.py
index e2489854..3a100446 100644
--- a/tests/test_trigger_factory.py
+++ b/tests/test_trigger_factory.py
@@ -105,8 +105,8 @@ def _fetch_parameter_options(
         del credentials
         del parameter
         return [
-            ParameterOption(value="option1", label=I18nObject(en_us="Option 1")),
-            ParameterOption(value="option2", label=I18nObject(en_us="Option 2")),
+            ParameterOption(value="option1", label=I18nObject(en_US="Option 1")),
+            ParameterOption(value="option2", label=I18nObject(en_US="Option 2")),
         ]
 
 
@@ -140,8 +140,8 @@ def test_trigger_factory_register_and_get_provider() -> None:
         identity=TriggerProviderIdentity(
             author="test",
             name="test_provider",
-            label=I18nObject(en_us="Test Provider"),
-            description=I18nObject(en_us="Test Provider Description"),
+            label=I18nObject(en_US="Test Provider"),
+            description=I18nObject(en_US="Test Provider Description"),
         ),
         subscription_constructor=TriggerSubscriptionConstructorConfiguration(
             parameters=[],
@@ -162,16 +162,16 @@ def test_trigger_factory_register_and_get_provider() -> None:
         identity=EventIdentity(
             author="test",
             name="test_event",
-            label=I18nObject(en_us="Test Event"),
+            label=I18nObject(en_US="Test Event"),
         ),
         parameters=[
             EventParameter(
                 name="test_param",
-                label=I18nObject(en_us="Test Parameter"),
+                label=I18nObject(en_US="Test Parameter"),
                 type=EventParameter.EventParameterType.STRING,
             ),
         ],
-        description=I18nObject(en_us="Human description"),
+        description=I18nObject(en_US="Human description"),
         extra=EventConfigurationExtra(
             python=EventConfigurationExtra.Python(source="test_event.py"),
         ),
@@ -214,8 +214,8 @@ def test_trigger_factory_subscription_constructor() -> None:
         identity=TriggerProviderIdentity(
             author="test",
             name="test_provider",
-            label=I18nObject(en_us="Test Provider"),
-            description=I18nObject(en_us="Test Provider Description"),
+            label=I18nObject(en_US="Test Provider"),
+            description=I18nObject(en_US="Test Provider Description"),
         ),
         subscription_constructor=TriggerSubscriptionConstructorConfiguration(
             parameters=[],
@@ -262,8 +262,8 @@ def test_trigger_factory_trigger_events() -> None:
         identity=TriggerProviderIdentity(
             author="test",
             name="test_provider",
-            label=I18nObject(en_us="Test Provider"),
-            description=I18nObject(en_us="Test Provider Description"),
+            label=I18nObject(en_US="Test Provider"),
+            description=I18nObject(en_US="Test Provider Description"),
         ),
         extra=TriggerProviderConfigurationExtra(
             python=TriggerProviderConfigurationExtra.Python(source="test_provider.py"),
@@ -274,10 +274,10 @@ def test_trigger_factory_trigger_events() -> None:
         identity=EventIdentity(
             author="test",
             name="test_event",
-            label=I18nObject(en_us="Test Event"),
+            label=I18nObject(en_US="Test Event"),
         ),
         parameters=[],
-        description=I18nObject(en_us="Human description"),
+        description=I18nObject(en_US="Human description"),
         extra=EventConfigurationExtra(
             python=EventConfigurationExtra.Python(source="test_event.py"),
         ),
@@ -343,8 +343,8 @@ def test_trigger_factory_error_handling() -> None:
         identity=TriggerProviderIdentity(
             author="test",
             name="test_provider",
-            label=I18nObject(en_us="Test Provider"),
-            description=I18nObject(en_us="Test Provider Description"),
+            label=I18nObject(en_US="Test Provider"),
+            description=I18nObject(en_US="Test Provider Description"),
         ),
         extra=TriggerProviderConfigurationExtra(
             python=TriggerProviderConfigurationExtra.Python(source="test_provider.py"),