diff --git a/api/core/app/apps/advanced_chat/app_generator.py b/api/core/app/apps/advanced_chat/app_generator.py
index 5a1e5973cd46ea..e7c9ebe09749de 100644
--- a/api/core/app/apps/advanced_chat/app_generator.py
+++ b/api/core/app/apps/advanced_chat/app_generator.py
@@ -4,7 +4,7 @@
 import threading
 import uuid
 from collections.abc import Generator
-from typing import Union
+from typing import Literal, Union, overload
 
 from flask import Flask, current_app
 from pydantic import ValidationError
@@ -39,6 +39,26 @@
 
 
 class AdvancedChatAppGenerator(MessageBasedAppGenerator):
+    @overload
+    def generate(
+        self, app_model: App,
+        workflow: Workflow,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[True] = True,
+    ) -> Generator[str, None, None]: ...
+
+    @overload
+    def generate(
+        self, app_model: App,
+        workflow: Workflow,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[False] = False,
+    ) -> dict: ...
+
     def generate(
         self, app_model: App,
         workflow: Workflow,
diff --git a/api/core/app/apps/agent_chat/app_generator.py b/api/core/app/apps/agent_chat/app_generator.py
index 53780bdfb003b2..daf37f4a50dd31 100644
--- a/api/core/app/apps/agent_chat/app_generator.py
+++ b/api/core/app/apps/agent_chat/app_generator.py
@@ -3,7 +3,7 @@
 import threading
 import uuid
 from collections.abc import Generator
-from typing import Any, Union
+from typing import Any, Literal, Union, overload
 
 from flask import Flask, current_app
 from pydantic import ValidationError
@@ -28,6 +28,24 @@
 
 
 class AgentChatAppGenerator(MessageBasedAppGenerator):
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[True] = True,
+    ) -> Generator[dict, None, None]: ...
+
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[False] = False,
+    ) -> dict: ...
+
     def generate(self, app_model: App,
                  user: Union[Account, EndUser],
                  args: Any,
diff --git a/api/core/app/apps/chat/app_generator.py b/api/core/app/apps/chat/app_generator.py
index 5b896e28455340..ab15928b744b61 100644
--- a/api/core/app/apps/chat/app_generator.py
+++ b/api/core/app/apps/chat/app_generator.py
@@ -3,7 +3,7 @@
 import threading
 import uuid
 from collections.abc import Generator
-from typing import Any, Union
+from typing import Any, Literal, Union, overload
 
 from flask import Flask, current_app
 from pydantic import ValidationError
@@ -28,13 +28,31 @@
 
 
 class ChatAppGenerator(MessageBasedAppGenerator):
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: Any,
+        invoke_from: InvokeFrom,
+        stream: Literal[True] = True,
+    ) -> Generator[str, None, None]: ...
+
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: Any,
+        invoke_from: InvokeFrom,
+        stream: Literal[False] = False,
+    ) -> dict: ...
+
     def generate(
         self, app_model: App,
         user: Union[Account, EndUser],
         args: Any,
         invoke_from: InvokeFrom,
         stream: bool = True,
-    ) -> Union[dict, Generator[dict, None, None]]:
+    ) -> Union[dict, Generator[str, None, None]]:
         """
         Generate App response.
 
diff --git a/api/core/app/apps/completion/app_generator.py b/api/core/app/apps/completion/app_generator.py
index c4e1caf65a9679..c0b13b40fdb0d6 100644
--- a/api/core/app/apps/completion/app_generator.py
+++ b/api/core/app/apps/completion/app_generator.py
@@ -3,7 +3,7 @@
 import threading
 import uuid
 from collections.abc import Generator
-from typing import Any, Union
+from typing import Any, Literal, Union, overload
 
 from flask import Flask, current_app
 from pydantic import ValidationError
@@ -30,12 +30,30 @@
 
 
 class CompletionAppGenerator(MessageBasedAppGenerator):
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[True] = True,
+    ) -> Generator[str, None, None]: ...
+
+    @overload
+    def generate(
+        self, app_model: App,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[False] = False,
+    ) -> dict: ...
+
     def generate(self, app_model: App,
                  user: Union[Account, EndUser],
                  args: Any,
                  invoke_from: InvokeFrom,
                  stream: bool = True) \
-            -> Union[dict, Generator[dict, None, None]]:
+            -> Union[dict, Generator[str, None, None]]:
         """
         Generate App response.
 
@@ -203,7 +221,7 @@ def generate_more_like_this(self, app_model: App,
                                 user: Union[Account, EndUser],
                                 invoke_from: InvokeFrom,
                                 stream: bool = True) \
-            -> Union[dict, Generator[dict, None, None]]:
+            -> Union[dict, Generator[str, None, None]]:
         """
         Generate App response.
 
diff --git a/api/core/app/apps/workflow/app_generator.py b/api/core/app/apps/workflow/app_generator.py
index df40aec154a856..26bb6c0f4f70b8 100644
--- a/api/core/app/apps/workflow/app_generator.py
+++ b/api/core/app/apps/workflow/app_generator.py
@@ -4,7 +4,7 @@
 import threading
 import uuid
 from collections.abc import Generator
-from typing import Union
+from typing import Literal, Union, overload
 
 from flask import Flask, current_app
 from pydantic import ValidationError
@@ -32,6 +32,26 @@
 
 
 class WorkflowAppGenerator(BaseAppGenerator):
+    @overload
+    def generate(
+        self, app_model: App,
+        workflow: Workflow,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[True] = True,
+    ) -> Generator[str, None, None]: ...
+
+    @overload
+    def generate(
+        self, app_model: App,
+        workflow: Workflow,
+        user: Union[Account, EndUser],
+        args: dict,
+        invoke_from: InvokeFrom,
+        stream: Literal[False] = False,
+    ) -> dict: ...
+
     def generate(
         self, app_model: App,
         workflow: Workflow,
@@ -107,7 +127,7 @@ def _generate(
         application_generate_entity: WorkflowAppGenerateEntity,
         invoke_from: InvokeFrom,
         stream: bool = True,
-    ) -> Union[dict, Generator[dict, None, None]]:
+    ) -> Union[dict, Generator[str, None, None]]:
         """
         Generate App response.