diff --git a/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_channel_service_routes.py b/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_channel_service_routes.py
index 3c7e5bcb..4aad06ef 100644
--- a/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_channel_service_routes.py
+++ b/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_channel_service_routes.py
@@ -3,7 +3,7 @@
 
 """Channel service route definitions (framework-agnostic logic)."""
 
-from typing import Type
+from typing import Type, TypeVar
 
 from microsoft_agents.activity import (
     AgentsModel,
@@ -16,6 +16,8 @@
 
 from ._http_request_protocol import HttpRequestProtocol
 
+AgentsModelT = TypeVar("AgentsModelT", bound=AgentsModel)
+
 
 class ChannelServiceRoutes:
     """Defines the Channel Service API routes and their handlers.
@@ -36,8 +38,8 @@ def __init__(self, handler: ChannelApiHandlerProtocol, base_url: str = ""):
 
     @staticmethod
     async def deserialize_from_body(
-        request: HttpRequestProtocol, target_model: Type[AgentsModel]
-    ) -> AgentsModel:
+        request: HttpRequestProtocol, target_model: Type[AgentsModelT]
+    ) -> AgentsModelT:
         """Deserialize request body to target model."""
         content_type = request.headers.get("Content-Type", "")
         if "application/json" not in content_type:
@@ -47,7 +49,9 @@ async def deserialize_from_body(
         return target_model.model_validate(body)
 
     @staticmethod
-    def serialize_model(model_or_list: AgentsModel | list[AgentsModel]) -> dict:
+    def serialize_model(
+        model_or_list: AgentsModelT | list[AgentsModelT],
+    ) -> dict | list[dict]:
         """Serialize model or list of models to JSON-compatible dict."""
         if isinstance(model_or_list, AgentsModel):
             return model_or_list.model_dump(
@@ -60,7 +64,9 @@ def serialize_model(model_or_list: AgentsModel | list[AgentsModel]) -> dict:
             ]
 
     # Route handler methods
-    async def send_to_conversation(self, request: HttpRequestProtocol) -> dict:
+    async def send_to_conversation(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle POST /v3/conversations/{conversation_id}/activities."""
         activity = await self.deserialize_from_body(request, Activity)
         conversation_id = request.get_path_param("conversation_id")
@@ -71,7 +77,9 @@ async def send_to_conversation(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def reply_to_activity(self, request: HttpRequestProtocol) -> dict:
+    async def reply_to_activity(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle POST /v3/conversations/{conversation_id}/activities/{activity_id}."""
         activity = await self.deserialize_from_body(request, Activity)
         conversation_id = request.get_path_param("conversation_id")
@@ -84,7 +92,7 @@ async def reply_to_activity(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def update_activity(self, request: HttpRequestProtocol) -> dict:
+    async def update_activity(self, request: HttpRequestProtocol) -> dict | list[dict]:
         """Handle PUT /v3/conversations/{conversation_id}/activities/{activity_id}."""
         activity = await self.deserialize_from_body(request, Activity)
         conversation_id = request.get_path_param("conversation_id")
@@ -107,7 +115,9 @@ async def delete_activity(self, request: HttpRequestProtocol) -> None:
             activity_id,
         )
 
-    async def get_activity_members(self, request: HttpRequestProtocol) -> dict:
+    async def get_activity_members(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle GET /v3/conversations/{conversation_id}/activities/{activity_id}/members."""
         conversation_id = request.get_path_param("conversation_id")
         activity_id = request.get_path_param("activity_id")
@@ -118,7 +128,9 @@ async def get_activity_members(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def create_conversation(self, request: HttpRequestProtocol) -> dict:
+    async def create_conversation(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle POST /."""
         conversation_parameters = await self.deserialize_from_body(
             request, ConversationParameters
@@ -128,7 +140,9 @@ async def create_conversation(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def get_conversations(self, request: HttpRequestProtocol) -> dict:
+    async def get_conversations(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle GET /."""
         # TODO: continuation token? conversation_id?
         result = await self.handler.on_get_conversations(
@@ -136,7 +150,9 @@ async def get_conversations(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def get_conversation_members(self, request: HttpRequestProtocol) -> dict:
+    async def get_conversation_members(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle GET /v3/conversations/{conversation_id}/members."""
         conversation_id = request.get_path_param("conversation_id")
         result = await self.handler.on_get_conversation_members(
@@ -145,7 +161,9 @@ async def get_conversation_members(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def get_conversation_member(self, request: HttpRequestProtocol) -> dict:
+    async def get_conversation_member(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle GET /v3/conversations/{conversation_id}/members/{member_id}."""
         conversation_id = request.get_path_param("conversation_id")
         member_id = request.get_path_param("member_id")
@@ -158,7 +176,7 @@ async def get_conversation_member(self, request: HttpRequestProtocol) -> dict:
 
     async def get_conversation_paged_members(
         self, request: HttpRequestProtocol
-    ) -> dict:
+    ) -> dict | list[dict]:
         """Handle GET /v3/conversations/{conversation_id}/pagedmembers."""
         conversation_id = request.get_path_param("conversation_id")
         # TODO: continuation token? page size?
@@ -168,18 +186,19 @@ async def get_conversation_paged_members(
         )
         return self.serialize_model(result)
 
-    async def delete_conversation_member(self, request: HttpRequestProtocol) -> dict:
+    async def delete_conversation_member(self, request: HttpRequestProtocol) -> None:
         """Handle DELETE /v3/conversations/{conversation_id}/members/{member_id}."""
         conversation_id = request.get_path_param("conversation_id")
         member_id = request.get_path_param("member_id")
-        result = await self.handler.on_delete_conversation_member(
+        await self.handler.on_delete_conversation_member(
             request.get_claims_identity(),
             conversation_id,
             member_id,
         )
-        return self.serialize_model(result)
 
-    async def send_conversation_history(self, request: HttpRequestProtocol) -> dict:
+    async def send_conversation_history(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle POST /v3/conversations/{conversation_id}/activities/history."""
         conversation_id = request.get_path_param("conversation_id")
         transcript = await self.deserialize_from_body(request, Transcript)
@@ -190,7 +209,9 @@ async def send_conversation_history(self, request: HttpRequestProtocol) -> dict:
         )
         return self.serialize_model(result)
 
-    async def upload_attachment(self, request: HttpRequestProtocol) -> dict:
+    async def upload_attachment(
+        self, request: HttpRequestProtocol
+    ) -> dict | list[dict]:
         """Handle POST /v3/conversations/{conversation_id}/attachments."""
         conversation_id = request.get_path_param("conversation_id")
         attachment_data = await self.deserialize_from_body(request, AttachmentData)
diff --git a/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_http_response.py b/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_http_response.py
index 955ff2ad..efe68657 100644
--- a/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_http_response.py
+++ b/libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/http/_http_response.py
@@ -28,7 +28,7 @@ def ok(body: Any = None) -> HttpResponse:
     @staticmethod
     def accepted() -> HttpResponse:
         """Create 202 Accepted response."""
-        return HttpResponse(status_code=202)
+        return HttpResponse(status_code=202, content_type=None)
 
     @staticmethod
     def json(body: Any, status_code: int = 200) -> HttpResponse: