diff --git a/python/docs/src/conf.py b/python/docs/src/conf.py
index aa730556b..f0e1a7a63 100644
--- a/python/docs/src/conf.py
+++ b/python/docs/src/conf.py
@@ -18,7 +18,8 @@ extensions = [
     "sphinx.ext.autosummary",
     "sphinx.ext.napoleon",
     "sphinxcontrib.apidoc",
-    "myst_parser"
+    "myst_parser",
+    "sphinx.ext.intersphinx"
 ]
 
 apidoc_module_dir = '../../src/agnext'
@@ -54,4 +55,6 @@ html_theme_options = {
 autodoc_default_options = {
     "members": True,
     "undoc-members": True,
-}
\ No newline at end of file
+}
+
+intersphinx_mapping = {'python': ('https://docs.python.org/3', None)}
\ No newline at end of file
diff --git a/python/examples/common/agents/_chat_completion_agent.py b/python/examples/common/agents/_chat_completion_agent.py
index 8cb98a2d8..302c44aff 100644
--- a/python/examples/common/agents/_chat_completion_agent.py
+++ b/python/examples/common/agents/_chat_completion_agent.py
@@ -189,10 +189,12 @@ class ChatCompletionAgent(TypeRoutedAgent):
             and all(isinstance(x, FunctionCall) for x in response.content)
         ):
             # Send a function call message to itself.
-            response = await self.send_message(
-                message=FunctionCallMessage(content=response.content, source=self.metadata["name"]),
-                recipient=self.id,
-                cancellation_token=cancellation_token,
+            response = await (
+                await self.send_message(
+                    message=FunctionCallMessage(content=response.content, source=self.metadata["name"]),
+                    recipient=self.id,
+                    cancellation_token=cancellation_token,
+                )
             )
             # Make an assistant message from the response.
             hisorical_messages = await self._memory.get_messages()
diff --git a/python/examples/common/agents/_image_generation_agent.py b/python/examples/common/agents/_image_generation_agent.py
index 9c90003d9..f20d55c3e 100644
--- a/python/examples/common/agents/_image_generation_agent.py
+++ b/python/examples/common/agents/_image_generation_agent.py
@@ -57,7 +57,7 @@ class ImageGenerationAgent(TypeRoutedAgent):
         image is published as a MultiModalMessage."""
 
         response = await self._generate_response(cancellation_token)
-        self.publish_message(response)
+        await self.publish_message(response)
 
     async def _generate_response(self, cancellation_token: CancellationToken) -> MultiModalMessage:
         messages = await self._memory.get_messages()
diff --git a/python/examples/common/patterns/_orchestrator_chat.py b/python/examples/common/patterns/_orchestrator_chat.py
index 84b974f7b..d59fd4819 100644
--- a/python/examples/common/patterns/_orchestrator_chat.py
+++ b/python/examples/common/patterns/_orchestrator_chat.py
@@ -51,7 +51,7 @@ class OrchestratorChat(TypeRoutedAgent):
         while total_turns < self._max_turns:
             # Reset all agents.
             for agent in [*self._specialists, self._orchestrator]:
-                await self.send_message(Reset(), agent)
+                await (await self.send_message(Reset(), agent))
 
             # Create the task specs.
             task_specs = f"""
@@ -73,7 +73,7 @@ Some additional points to consider:
 
             # Send the task specs to the orchestrator and specialists.
             for agent in [*self._specialists, self._orchestrator]:
-                await self.send_message(TextMessage(content=task_specs, source=self.metadata["name"]), agent)
+                await (await self.send_message(TextMessage(content=task_specs, source=self.metadata["name"]), agent))
 
             # Inner loop.
             stalled_turns = 0
@@ -127,9 +127,11 @@ Some additional points to consider:
 
                 # Update agents.
                 for agent in [*self._specialists, self._orchestrator]:
-                    _ = await self.send_message(
-                        TextMessage(content=subtask, source=self.metadata["name"]),
-                        agent,
+                    _ = await (
+                        await self.send_message(
+                            TextMessage(content=subtask, source=self.metadata["name"]),
+                            agent,
+                        )
                     )
 
                 # Find the speaker.
@@ -139,17 +141,19 @@ Some additional points to consider:
                     raise ValueError(f"Invalid next speaker: {data['next_speaker']['answer']}") from e
 
                 # Ask speaker to speak.
-                speaker_response = await self.send_message(RespondNow(), speaker)
+                speaker_response = await (await self.send_message(RespondNow(), speaker))
                 assert speaker_response is not None
 
                 # Update all other agents with the speaker's response.
                 for agent in [agent for agent in self._specialists if agent != speaker] + [self._orchestrator]:
-                    await self.send_message(
-                        TextMessage(
-                            content=speaker_response.content,
-                            source=speaker_response.source,
-                        ),
-                        agent,
+                    await (
+                        await self.send_message(
+                            TextMessage(
+                                content=speaker_response.content,
+                                source=speaker_response.source,
+                            ),
+                            agent,
+                        )
                     )
 
                 # Increment the total turns.
@@ -162,7 +166,7 @@ Some additional points to consider:
 
     async def _prepare_task(self, task: str, sender: str) -> Tuple[str, str, str, str]:
         # Reset planner.
-        await self.send_message(Reset(), self._planner)
+        await (await self.send_message(Reset(), self._planner))
 
         # A reusable description of the team.
         team = "\n".join(
@@ -199,8 +203,8 @@ When answering this survey, keep in mind that "facts" will typically be specific
 """.strip()
 
         # Ask the planner to obtain prior knowledge about facts.
-        await self.send_message(TextMessage(content=closed_book_prompt, source=sender), self._planner)
-        facts_response = await self.send_message(RespondNow(), self._planner)
+        await (await self.send_message(TextMessage(content=closed_book_prompt, source=sender), self._planner))
+        facts_response = await (await self.send_message(RespondNow(), self._planner))
 
         facts = str(facts_response.content)
 
@@ -213,7 +217,7 @@ Based on the team composition, and known and unknown facts, please devise a shor
 
         # Send second messag eto the planner.
         await self.send_message(TextMessage(content=plan_prompt, source=sender), self._planner)
-        plan_response = await self.send_message(RespondNow(), self._planner)
+        plan_response = await (await self.send_message(RespondNow(), self._planner))
         plan = str(plan_response.content)
 
         return team, names, facts, plan
@@ -265,11 +269,13 @@ Please output an answer in pure JSON format according to the following schema. T
         request = step_prompt
         while True:
             # Send a message to the orchestrator.
-            await self.send_message(TextMessage(content=request, source=sender), self._orchestrator)
+            await (await self.send_message(TextMessage(content=request, source=sender), self._orchestrator))
             # Request a response.
-            step_response = await self.send_message(
-                RespondNow(response_format=ResponseFormat.json_object),
-                self._orchestrator,
+            step_response = await (
+                await self.send_message(
+                    RespondNow(response_format=ResponseFormat.json_object),
+                    self._orchestrator,
+                )
             )
             # TODO: use typed dictionary.
             try:
@@ -328,9 +334,9 @@ Please output an answer in pure JSON format according to the following schema. T
 {facts}
 """.strip()
         # Send a message to the orchestrator.
-        await self.send_message(TextMessage(content=new_facts_prompt, source=sender), self._orchestrator)
+        await (await self.send_message(TextMessage(content=new_facts_prompt, source=sender), self._orchestrator))
         # Request a response.
-        new_facts_response = await self.send_message(RespondNow(), self._orchestrator)
+        new_facts_response = await (await self.send_message(RespondNow(), self._orchestrator))
         return str(new_facts_response.content)
 
     async def _educated_guess(self, facts: str, sender: str) -> Any:
@@ -353,14 +359,18 @@ Please output an answer in pure JSON format according to the following schema. T
         request = educated_guess_promt
         while True:
             # Send a message to the orchestrator.
-            await self.send_message(
-                TextMessage(content=request, source=sender),
-                self._orchestrator,
+            await (
+                await self.send_message(
+                    TextMessage(content=request, source=sender),
+                    self._orchestrator,
+                )
             )
             # Request a response.
-            response = await self.send_message(
-                RespondNow(response_format=ResponseFormat.json_object),
-                self._orchestrator,
+            response = await (
+                await self.send_message(
+                    RespondNow(response_format=ResponseFormat.json_object),
+                    self._orchestrator,
+                )
             )
             try:
                 result = json.loads(str(response.content))
@@ -387,7 +397,7 @@ Team membership:
 {team}
 """.strip()
         # Send a message to the orchestrator.
-        await self.send_message(TextMessage(content=new_plan_prompt, source=sender), self._orchestrator)
+        await (await self.send_message(TextMessage(content=new_plan_prompt, source=sender), self._orchestrator))
         # Request a response.
-        new_plan_response = await self.send_message(RespondNow(), self._orchestrator)
+        new_plan_response = await (await self.send_message(RespondNow(), self._orchestrator))
         return str(new_plan_response.content)
diff --git a/python/examples/core/inner_outer_direct.py b/python/examples/core/inner_outer_direct.py
index c657aa3a3..ac67bc9a8 100644
--- a/python/examples/core/inner_outer_direct.py
+++ b/python/examples/core/inner_outer_direct.py
@@ -47,7 +47,7 @@ async def main() -> None:
     runtime = SingleThreadedAgentRuntime()
     inner = runtime.register_and_get("inner", Inner)
     outer = runtime.register_and_get("outer", lambda: Outer(inner))
-    response = runtime.send_message(MessageType(body="Hello", sender="external"), outer)
+    response = await runtime.send_message(MessageType(body="Hello", sender="external"), outer)
 
     while not response.done():
         await runtime.process_next()
diff --git a/python/examples/core/one_agent_direct.py b/python/examples/core/one_agent_direct.py
index 576f04eda..ae6dc2162 100644
--- a/python/examples/core/one_agent_direct.py
+++ b/python/examples/core/one_agent_direct.py
@@ -46,7 +46,7 @@ async def main() -> None:
 
     # Send a message to the agent.
     message = Message(content="Can you tell me something fun about SF?")
-    result = runtime.send_message(message, agent)
+    result = await runtime.send_message(message, agent)
 
     # Process messages until the agent responds.
     while result.done() is False:
diff --git a/python/examples/core/two_agents_pub_sub_termination.py b/python/examples/core/two_agents_pub_sub_termination.py
index 05a0e68f6..4b42fc903 100644
--- a/python/examples/core/two_agents_pub_sub_termination.py
+++ b/python/examples/core/two_agents_pub_sub_termination.py
@@ -64,7 +64,7 @@ class ChatCompletionAgent(TypeRoutedAgent):
     async def handle_message(self, message: Message, cancellation_token: CancellationToken) -> None:
         self._memory.append(message)
         if self._termination_word in message.content:
-            self.publish_message(Termination())
+            await self.publish_message(Termination())
             return
         llm_messages: List[LLMMessage] = []
         for m in self._memory[-10:]:
@@ -74,7 +74,7 @@ class ChatCompletionAgent(TypeRoutedAgent):
                 llm_messages.append(UserMessage(content=m.content, source=m.source))
         response = await self._model_client.create(self._system_messages + llm_messages)
         assert isinstance(response.content, str)
-        self.publish_message(Message(content=response.content, source=self.metadata["name"]))
+        await self.publish_message(Message(content=response.content, source=self.metadata["name"]))
 
 
 class TerminationHandler(DefaultInterventionHandler):
@@ -126,7 +126,7 @@ async def main() -> None:
 
     # Send a message to Jack to start the conversation.
     message = Message(content="Can you tell me something fun about SF?", source="User")
-    runtime.send_message(message, jack)
+    await runtime.send_message(message, jack)
 
     # Process messages until termination.
     while not termination_handler.terminated:
diff --git a/python/examples/demos/assistant.py b/python/examples/demos/assistant.py
index f01b89d44..a753c0637 100644
--- a/python/examples/demos/assistant.py
+++ b/python/examples/demos/assistant.py
@@ -228,7 +228,7 @@ Type "exit" to exit the chat.
     user = assistant_chat(runtime)
     print(usage)
     # Request the user to start the conversation.
-    runtime.send_message(PublishNow(), user)
+    await runtime.send_message(PublishNow(), user)
     while True:
         # TODO: have a way to exit the loop.
         await runtime.process_next()
diff --git a/python/examples/demos/chess_game.py b/python/examples/demos/chess_game.py
index 4807fc1ac..d529131da 100644
--- a/python/examples/demos/chess_game.py
+++ b/python/examples/demos/chess_game.py
@@ -205,7 +205,7 @@ async def main() -> None:
     runtime = SingleThreadedAgentRuntime()
     chess_game(runtime)
     # Publish an initial message to trigger the group chat manager to start orchestration.
-    runtime.publish_message(TextMessage(content="Game started.", source="System"), namespace="default")
+    await runtime.publish_message(TextMessage(content="Game started.", source="System"), namespace="default")
     while True:
         await runtime.process_next()
         await asyncio.sleep(1)
diff --git a/python/examples/patterns/coder_executor_pub_sub.py b/python/examples/patterns/coder_executor_pub_sub.py
index 27a4b4960..7d97f56b3 100644
--- a/python/examples/patterns/coder_executor_pub_sub.py
+++ b/python/examples/patterns/coder_executor_pub_sub.py
@@ -100,7 +100,7 @@ Reply "TERMINATE" in the end when everything is done."""
         )
 
         # Publish the code execution task.
-        self.publish_message(
+        await self.publish_message(
             CodeExecutionTask(content=response.content, session_id=session_id), cancellation_token=cancellation_token
         )
 
@@ -120,11 +120,11 @@ Reply "TERMINATE" in the end when everything is done."""
 
         if "TERMINATE" in response.content:
             # If the task is completed, publish a message with the completion content.
-            self.publish_message(TaskCompletion(content=response.content), cancellation_token=cancellation_token)
+            await self.publish_message(TaskCompletion(content=response.content), cancellation_token=cancellation_token)
             return
 
         # Publish the code execution task.
-        self.publish_message(
+        await self.publish_message(
             CodeExecutionTask(content=response.content, session_id=message.session_id),
             cancellation_token=cancellation_token,
         )
@@ -143,7 +143,7 @@ class Executor(TypeRoutedAgent):
         code_blocks = self._extract_code_blocks(message.content)
         if not code_blocks:
             # If no code block is found, publish a message with an error.
-            self.publish_message(
+            await self.publish_message(
                 CodeExecutionTaskResult(
                     output="Error: no Markdown code block found.", exit_code=1, session_id=message.session_id
                 ),
@@ -155,7 +155,7 @@ class Executor(TypeRoutedAgent):
         cancellation_token.link_future(future)
         result = await future
         # Publish the code execution result.
-        self.publish_message(
+        await self.publish_message(
             CodeExecutionTaskResult(output=result.output, exit_code=result.exit_code, session_id=message.session_id),
             cancellation_token=cancellation_token,
         )
@@ -202,7 +202,7 @@ async def main(task: str, temp_dir: str) -> None:
     runtime.register("executor", lambda: Executor(executor=LocalCommandLineCodeExecutor(work_dir=temp_dir)))
 
     # Publish the task message.
-    runtime.publish_message(TaskMessage(content=task), namespace="default")
+    await runtime.publish_message(TaskMessage(content=task), namespace="default")
 
     # Run the runtime until the termination condition is met.
     while not termination_handler.terminated:
diff --git a/python/examples/patterns/coder_reviewer_direct.py b/python/examples/patterns/coder_reviewer_direct.py
index d10b61f61..a57439341 100644
--- a/python/examples/patterns/coder_reviewer_direct.py
+++ b/python/examples/patterns/coder_reviewer_direct.py
@@ -184,7 +184,7 @@ Code: <Your code>
             # Send the code review task to the reviewer.
             result = await self.send_message(code_review_task, self._reviewer)
             # Store the review result in the session memory.
-            memory.append(result)
+            memory.append(await result)
         # Obtain the request from previous messages.
         review_request = next(m for m in reversed(memory) if isinstance(m, CodeReviewTask))
         assert review_request is not None
@@ -222,7 +222,7 @@ async def main() -> None:
             reviewer=reviewer,
         ),
     )
-    result = runtime.send_message(
+    result = await runtime.send_message(
         message=CodeWritingTask(
             task="Write a function to find the directory with the largest number of files using multi-processing."
         ),
diff --git a/python/examples/patterns/coder_reviewer_pub_sub.py b/python/examples/patterns/coder_reviewer_pub_sub.py
index d6f18ce7b..09117d3b4 100644
--- a/python/examples/patterns/coder_reviewer_pub_sub.py
+++ b/python/examples/patterns/coder_reviewer_pub_sub.py
@@ -281,7 +281,7 @@ async def main() -> None:
             model_client=OpenAIChatCompletionClient(model="gpt-3.5-turbo"),
         ),
     )
-    runtime.publish_message(
+    await runtime.publish_message(
         message=CodeWritingTask(
             task="Write a function to find the directory with the largest number of files using multi-processing."
         ),
diff --git a/python/examples/patterns/group_chat_pub_sub.py b/python/examples/patterns/group_chat_pub_sub.py
index 74da99ad0..f86dcf901 100644
--- a/python/examples/patterns/group_chat_pub_sub.py
+++ b/python/examples/patterns/group_chat_pub_sub.py
@@ -65,10 +65,10 @@ class RoundRobinGroupChatManager(TypeRoutedAgent):
         self._round_count += 1
         if self._round_count == self._num_rounds * len(self._participants):
             # End the conversation after the specified number of rounds.
-            self.publish_message(Termination())
+            await self.publish_message(Termination())
             return
         # Send a request to speak message to the selected speaker.
-        self.send_message(RequestToSpeak(), speaker)
+        await self.send_message(RequestToSpeak(), speaker)
 
 
 class GroupChatParticipant(TypeRoutedAgent):
@@ -102,7 +102,7 @@ class GroupChatParticipant(TypeRoutedAgent):
         assert isinstance(response.content, str)
         speach = Message(content=response.content, source=self.metadata["name"])
         self._memory.append(speach)
-        self.publish_message(speach)
+        await self.publish_message(speach)
 
 
 class TerminationHandler(DefaultInterventionHandler):
@@ -165,7 +165,7 @@ async def main() -> None:
     )
 
     # Start the conversation.
-    runtime.publish_message(Message(content="Hello, everyone!", source="Moderator"), namespace="default")
+    await runtime.publish_message(Message(content="Hello, everyone!", source="Moderator"), namespace="default")
 
     # Run the runtime until termination.
     while not termination_handler.terminated:
diff --git a/python/examples/patterns/mixture_of_agents_direct.py b/python/examples/patterns/mixture_of_agents_direct.py
index bc8c8e3f5..f54f0fe5c 100644
--- a/python/examples/patterns/mixture_of_agents_direct.py
+++ b/python/examples/patterns/mixture_of_agents_direct.py
@@ -83,7 +83,7 @@ class AggregatorAgent(TypeRoutedAgent):
         and aggregates the results."""
         ref_task = ReferenceAgentTask(task=message.task)
         results: List[ReferenceAgentTaskResult] = await asyncio.gather(
-            *[self.send_message(ref_task, ref) for ref in self._references]
+            *[await self.send_message(ref_task, ref) for ref in self._references]
         )
         combined_result = "\n\n".join([r.result for r in results])
         response = await self._model_client.create(
@@ -132,7 +132,7 @@ async def main() -> None:
             references=[ref1, ref2, ref3],
         ),
     )
-    result = runtime.send_message(AggregatorTask(task="What are something fun to do in SF?"), agg)
+    result = await runtime.send_message(AggregatorTask(task="What are something fun to do in SF?"), agg)
     while result.done() is False:
         await runtime.process_next()
     print(result.result())
diff --git a/python/examples/patterns/multi_agent_debate_pub_sub.py b/python/examples/patterns/multi_agent_debate_pub_sub.py
index 38eb08174..2d9faddec 100644
--- a/python/examples/patterns/multi_agent_debate_pub_sub.py
+++ b/python/examples/patterns/multi_agent_debate_pub_sub.py
@@ -128,7 +128,11 @@ class MathSolver(TypeRoutedAgent):
             "Your final answer should be a single numerical number, "
             "in the form of {{answer}}, at the end of your response."
             # Send the question to the agent itself.
-            self.send_message(SolverRequest(content=prompt, session_id=message.session_id, question=question), self.id)
+            await (
+                await self.send_message(
+                    SolverRequest(content=prompt, session_id=message.session_id, question=question), self.id
+                )
+            )
             # Clear the buffer.
             self._buffer.clear()
 
@@ -192,7 +196,7 @@ class MathAggregator(TypeRoutedAgent):
             answers = [resp.answer for resp in self._responses[message.session_id]]
             majority_answer = max(set(answers), key=answers.count)
             # Publish the aggregated response.
-            self.publish_message(Answer(content=majority_answer))
+            await self.publish_message(Answer(content=majority_answer))
             # Clear the responses.
             self._responses.pop(message.session_id)
 
diff --git a/python/examples/patterns/orchestrator.py b/python/examples/patterns/orchestrator.py
index a0b5e4fee..c171da867 100644
--- a/python/examples/patterns/orchestrator.py
+++ b/python/examples/patterns/orchestrator.py
@@ -130,7 +130,7 @@ def software_development(runtime: AgentRuntime) -> OrchestratorChat:  # type: ig
 async def run(message: str, user: str, scenario: Callable[[AgentRuntime], OrchestratorChat]) -> None:  # type: ignore
     runtime = SingleThreadedAgentRuntime()
     chat = scenario(runtime)
-    response = runtime.send_message(TextMessage(content=message, source=user), chat.id)
+    response = await runtime.send_message(TextMessage(content=message, source=user), chat.id)
     while not response.done():
         await runtime.process_next()
     print((await response).content)  # type: ignore
diff --git a/python/examples/tool-use/coding_one_agent_direct.py b/python/examples/tool-use/coding_one_agent_direct.py
index f2739d3bb..75e775b7b 100644
--- a/python/examples/tool-use/coding_one_agent_direct.py
+++ b/python/examples/tool-use/coding_one_agent_direct.py
@@ -78,8 +78,8 @@ class ToolEnabledAgent(TypeRoutedAgent):
 
         # Keep executing the tools until the response is not a list of function calls.
         while isinstance(response.content, list) and all(isinstance(item, FunctionCall) for item in response.content):
-            results = await asyncio.gather(
-                *[self.send_message(ToolExecutionTask(function_call=call), self.id) for call in response.content]
+            results: List[ToolExecutionTaskResult] = await asyncio.gather(
+                *[await self.send_message(ToolExecutionTask(function_call=call), self.id) for call in response.content]
             )
             # Combine the results into a single response.
             result = FunctionExecutionResultMessage(content=[result.result for result in results])
@@ -136,7 +136,9 @@ async def main() -> None:
     )
 
     # Send a task to the tool user.
-    result = runtime.send_message(UserRequest("Run the following Python code: print('Hello, World!')"), tool_agent)
+    result = await runtime.send_message(
+        UserRequest("Run the following Python code: print('Hello, World!')"), tool_agent
+    )
 
     # Run the runtime until the task is completed.
     while not result.done():
diff --git a/python/examples/tool-use/coding_two_agent_pub_sub.py b/python/examples/tool-use/coding_two_agent_pub_sub.py
index c4e2138a4..0f3a663c1 100644
--- a/python/examples/tool-use/coding_two_agent_pub_sub.py
+++ b/python/examples/tool-use/coding_two_agent_pub_sub.py
@@ -218,7 +218,9 @@ async def main() -> None:
     )
 
     # Publish a task.
-    runtime.publish_message(UserRequest("Run the following Python code: print('Hello, World!')"), namespace="default")
+    await runtime.publish_message(
+        UserRequest("Run the following Python code: print('Hello, World!')"), namespace="default"
+    )
 
     # Run the runtime until termination.
     while not termination_handler.terminated:
diff --git a/python/examples/tool-use/custom_function_tool_one_agent_direct.py b/python/examples/tool-use/custom_function_tool_one_agent_direct.py
index 6c6238397..0b6acf983 100644
--- a/python/examples/tool-use/custom_function_tool_one_agent_direct.py
+++ b/python/examples/tool-use/custom_function_tool_one_agent_direct.py
@@ -49,7 +49,7 @@ async def main() -> None:
     )
 
     # Send a task to the tool user.
-    result = runtime.send_message(UserRequest("What is the stock price of NVDA on 2024/06/01"), tool_agent)
+    result = await runtime.send_message(UserRequest("What is the stock price of NVDA on 2024/06/01"), tool_agent)
 
     # Run the runtime until the task is completed.
     while not result.done():
diff --git a/python/pyproject.toml b/python/pyproject.toml
index 172d32bf6..4c94d9a2e 100644
--- a/python/pyproject.toml
+++ b/python/pyproject.toml
@@ -18,8 +18,7 @@ dependencies = [
     "pillow",
     "aiohttp",
     "typing-extensions",
-    "pydantic>=1.10,<3",
-    "types-aiofiles"
+    "pydantic>=1.10,<3"
 ]
 
 [tool.hatch.envs.default]
diff --git a/python/src/agnext/application/_single_threaded_agent_runtime.py b/python/src/agnext/application/_single_threaded_agent_runtime.py
index 564807162..58140d8a9 100644
--- a/python/src/agnext/application/_single_threaded_agent_runtime.py
+++ b/python/src/agnext/application/_single_threaded_agent_runtime.py
@@ -106,7 +106,7 @@ class SingleThreadedAgentRuntime(AgentRuntime):
         return set(self._agent_factories.keys())
 
     # Returns the response of the message
-    def send_message(
+    async def send_message(
         self,
         message: Any,
         recipient: AgentId,
@@ -150,14 +150,14 @@ class SingleThreadedAgentRuntime(AgentRuntime):
 
         return future
 
-    def publish_message(
+    async def publish_message(
         self,
         message: Any,
         *,
         namespace: str | None = None,
         sender: AgentId | None = None,
         cancellation_token: CancellationToken | None = None,
-    ) -> Future[None]:
+    ) -> None:
         if cancellation_token is None:
             cancellation_token = CancellationToken()
 
@@ -196,10 +196,6 @@ class SingleThreadedAgentRuntime(AgentRuntime):
             )
         )
 
-        future = asyncio.get_event_loop().create_future()
-        future.set_result(None)
-        return future
-
     def save_state(self) -> Mapping[str, Any]:
         state: Dict[str, Dict[str, Any]] = {}
         for agent_id in self._instantiated_agents:
diff --git a/python/src/agnext/core/_agent.py b/python/src/agnext/core/_agent.py
index e4068f95b..4bb07ed3c 100644
--- a/python/src/agnext/core/_agent.py
+++ b/python/src/agnext/core/_agent.py
@@ -27,8 +27,9 @@ class Agent(Protocol):
         Returns:
             Any: Response to the message. Can be None.
 
-        Notes:
-            If there was a cancellation, this function should raise a `CancelledError`.
+        Raises:
+            asyncio.CancelledError: If the message was cancelled.
+            CantHandleException: If the agent cannot handle the message.
         """
         ...
 
diff --git a/python/src/agnext/core/_agent_proxy.py b/python/src/agnext/core/_agent_proxy.py
index f53890bfc..27b912c51 100644
--- a/python/src/agnext/core/_agent_proxy.py
+++ b/python/src/agnext/core/_agent_proxy.py
@@ -26,14 +26,14 @@ class AgentProxy:
         """Metadata of the agent."""
         return self._runtime.agent_metadata(self._agent)
 
-    def send_message(
+    async def send_message(
         self,
         message: Any,
         *,
         sender: AgentId,
         cancellation_token: CancellationToken | None = None,
     ) -> Future[Any]:
-        return self._runtime.send_message(
+        return await self._runtime.send_message(
             message,
             recipient=self._agent,
             sender=sender,
diff --git a/python/src/agnext/core/_agent_runtime.py b/python/src/agnext/core/_agent_runtime.py
index 5b423086c..c1e4a585a 100644
--- a/python/src/agnext/core/_agent_runtime.py
+++ b/python/src/agnext/core/_agent_runtime.py
@@ -20,24 +20,64 @@ agent_instantiation_context: ContextVar[tuple[AgentRuntime, AgentId]] = ContextV
 @runtime_checkable
 class AgentRuntime(Protocol):
     # Returns the response of the message
-    def send_message(
+    # Can raise CantHandleException
+    async def send_message(
         self,
         message: Any,
         recipient: AgentId,
         *,
         sender: AgentId | None = None,
         cancellation_token: CancellationToken | None = None,
-    ) -> Future[Any]: ...
+    ) -> Future[Any]:
+        """Send a message to an agent and return a future that will resolve to the response.
+
+        The act of sending a message may be asynchronous, and the response to the message itself is also asynchronous. For example:
+
+        .. code-block:: python
+
+            response_future = await runtime.send_message(MyMessage("Hello"), recipient=agent_id)
+            response = await response_future
+
+        The returned future only needs to be awaited if the response is needed. If the response is not needed, the future can be ignored.
+
+        Args:
+            message (Any): The message to send.
+            recipient (AgentId): The agent to send the message to.
+            sender (AgentId | None, optional): Agent which sent the message. Should **only** be None if this was sent from no agent, such as directly to the runtime externally. Defaults to None.
+            cancellation_token (CancellationToken | None, optional): Token used to cancel an in progress . Defaults to None.
+
+        Raises:
+            CantHandleException: If the recipient cannot handle the message.
+            UndeliverableException: If the message cannot be delivered.
+
+        Returns:
+            Future[Any]: A future that will resolve to the response of the message.
+        """
+
+        ...
 
     # No responses from publishing
-    def publish_message(
+    async def publish_message(
         self,
         message: Any,
         *,
         namespace: str | None = None,
         sender: AgentId | None = None,
         cancellation_token: CancellationToken | None = None,
-    ) -> Future[None]: ...
+    ) -> None:
+        """Publish a message to all agents in the given namespace, or if no namespace is provided, the namespace of the sender.
+
+        No responses are expected from publishing.
+
+        Args:
+            message (Any): The message to publish.
+            namespace (str | None, optional): The namespace to publish to. Defaults to None.
+            sender (AgentId | None, optional): The agent which sent the message. Defaults to None.
+            cancellation_token (CancellationToken | None, optional): Token used to cancel an in progress . Defaults to None.
+
+        Raises:
+            UndeliverableException: If the message cannot be delivered.
+        """
 
     @overload
     def register(
@@ -62,7 +102,7 @@ class AgentRuntime(Protocol):
 
         Args:
             name (str): The name of the type agent this factory creates.
-            agent_factory (Callable[[], T] | Callable[[AgentRuntime, AgentId], T]): The factory that creates the agent.
+            agent_factory (Callable[[], T] | Callable[[AgentRuntime, AgentId], T]): The factory that creates the agent, where T is a concrete Agent type.
 
 
         Example:
@@ -82,8 +122,29 @@ class AgentRuntime(Protocol):
 
         ...
 
-    def get(self, name: str, *, namespace: str = "default") -> AgentId: ...
-    def get_proxy(self, name: str, *, namespace: str = "default") -> AgentProxy: ...
+    def get(self, name: str, *, namespace: str = "default") -> AgentId:
+        """Get an agent by name and namespace.
+
+        Args:
+            name (str): The name of the agent.
+            namespace (str, optional): The namespace of the agent. Defaults to "default".
+
+        Returns:
+            AgentId: The agent id.
+        """
+        ...
+
+    def get_proxy(self, name: str, *, namespace: str = "default") -> AgentProxy:
+        """Get a proxy for an agent by name and namespace.
+
+        Args:
+            name (str): The name of the agent.
+            namespace (str, optional): The namespace of the agent. Defaults to "default".
+
+        Returns:
+            AgentProxy: The agent proxy.
+        """
+        ...
 
     @overload
     def register_and_get(
@@ -110,6 +171,16 @@ class AgentRuntime(Protocol):
         *,
         namespace: str = "default",
     ) -> AgentId:
+        """Register an agent factory with the runtime associated with a specific name and get the agent id. The name must be unique.
+
+        Args:
+            name (str): The name of the type agent this factory creates.
+            agent_factory (Callable[[], T] | Callable[[AgentRuntime, AgentId], T]): The factory that creates the agent, where T is a concrete Agent type.
+            namespace (str, optional): The namespace of the agent. Defaults to "default".
+
+        Returns:
+            AgentId: The agent id.
+        """
         self.register(name, agent_factory)
         return self.get(name, namespace=namespace)
 
@@ -138,15 +209,66 @@ class AgentRuntime(Protocol):
         *,
         namespace: str = "default",
     ) -> AgentProxy:
+        """Register an agent factory with the runtime associated with a specific name and get the agent proxy. The name must be unique.
+
+        Args:
+            name (str): The name of the type agent this factory creates.
+            agent_factory (Callable[[], T] | Callable[[AgentRuntime, AgentId], T]): The factory that creates the agent, where T is a concrete Agent type.
+            namespace (str, optional): The namespace of the agent. Defaults to "default".
+
+        Returns:
+            AgentProxy: The agent proxy.
+        """
         self.register(name, agent_factory)
         return self.get_proxy(name, namespace=namespace)
 
-    def save_state(self) -> Mapping[str, Any]: ...
+    def save_state(self) -> Mapping[str, Any]:
+        """Save the state of the entire runtime, including all hosted agents. The only way to restore the state is to pass it to :meth:`load_state`.
 
-    def load_state(self, state: Mapping[str, Any]) -> None: ...
+        The structure of the state is implementation defined and can be any JSON serializable object.
 
-    def agent_metadata(self, agent: AgentId) -> AgentMetadata: ...
+        Returns:
+            Mapping[str, Any]: The saved state.
+        """
+        ...
 
-    def agent_save_state(self, agent: AgentId) -> Mapping[str, Any]: ...
+    def load_state(self, state: Mapping[str, Any]) -> None:
+        """Load the state of the entire runtime, including all hosted agents. The state should be the same as the one returned by :meth:`save_state`.
 
-    def agent_load_state(self, agent: AgentId, state: Mapping[str, Any]) -> None: ...
+        Args:
+            state (Mapping[str, Any]): The saved state.
+        """
+        ...
+
+    def agent_metadata(self, agent: AgentId) -> AgentMetadata:
+        """Get the metadata for an agent.
+
+        Args:
+            agent (AgentId): The agent id.
+
+        Returns:
+            AgentMetadata: The agent metadata.
+        """
+        ...
+
+    def agent_save_state(self, agent: AgentId) -> Mapping[str, Any]:
+        """Save the state of a single agent.
+
+        The structure of the state is implementation defined and can be any JSON serializable object.
+
+        Args:
+            agent (AgentId): The agent id.
+
+        Returns:
+            Mapping[str, Any]: The saved state.
+        """
+        ...
+
+    def agent_load_state(self, agent: AgentId, state: Mapping[str, Any]) -> None:
+        """Load the state of a single agent.
+
+        Args:
+            agent (AgentId): The agent id.
+            state (Mapping[str, Any]): The saved state.
+        """
+        ...
diff --git a/python/src/agnext/core/_base_agent.py b/python/src/agnext/core/_base_agent.py
index 041328f62..909b68aad 100644
--- a/python/src/agnext/core/_base_agent.py
+++ b/python/src/agnext/core/_base_agent.py
@@ -49,18 +49,18 @@ class BaseAgent(ABC, Agent):
     @abstractmethod
     async def on_message(self, message: Any, cancellation_token: CancellationToken) -> Any: ...
 
-    # Returns the response of the message
-    def send_message(
+    async def send_message(
         self,
         message: Any,
         recipient: AgentId,
         *,
         cancellation_token: CancellationToken | None = None,
     ) -> Future[Any]:
+        """See :py:meth:`agnext.core.AgentRuntime.send_message` for more information."""
         if cancellation_token is None:
             cancellation_token = CancellationToken()
 
-        future = self._runtime.send_message(
+        future = await self._runtime.send_message(
             message,
             sender=self.id,
             recipient=recipient,
@@ -69,17 +69,13 @@ class BaseAgent(ABC, Agent):
         cancellation_token.link_future(future)
         return future
 
-    def publish_message(
+    async def publish_message(
         self,
         message: Any,
         *,
         cancellation_token: CancellationToken | None = None,
-    ) -> Future[None]:
-        if cancellation_token is None:
-            cancellation_token = CancellationToken()
-
-        future = self._runtime.publish_message(message, sender=self.id, cancellation_token=cancellation_token)
-        return future
+    ) -> None:
+        await self._runtime.publish_message(message, sender=self.id, cancellation_token=cancellation_token)
 
     def save_state(self) -> Mapping[str, Any]:
         warnings.warn("save_state not implemented", stacklevel=2)
diff --git a/python/teams/team-one/examples/example_coder.py b/python/teams/team-one/examples/example_coder.py
index 1d0ea6f2b..3d304ecce 100644
--- a/python/teams/team-one/examples/example_coder.py
+++ b/python/teams/team-one/examples/example_coder.py
@@ -18,7 +18,7 @@ async def main() -> None:
     task = TaskMessage(input(f"Enter a task for {coder.name}: "))
 
     # Send a task to the tool user.
-    result = runtime.send_message(task, coder)
+    result = await runtime.send_message(task, coder)
 
     # Run the runtime until the task is completed.
     while not result.done():
diff --git a/python/teams/team-one/examples/example_file_surfer.py b/python/teams/team-one/examples/example_file_surfer.py
index d6aacb190..2996d40f4 100644
--- a/python/teams/team-one/examples/example_file_surfer.py
+++ b/python/teams/team-one/examples/example_file_surfer.py
@@ -20,7 +20,7 @@ async def main() -> None:
     task = TaskMessage(input(f"Enter a task for {file_surfer.name}: "))
 
     # Send a task to the tool user.
-    result = runtime.send_message(task, file_surfer)
+    result = await runtime.send_message(task, file_surfer)
 
     # Run the runtime until the task is completed.
     while not result.done():
diff --git a/python/teams/team-one/pyproject.toml b/python/teams/team-one/pyproject.toml
index 78b192ca9..f3fb0117b 100644
--- a/python/teams/team-one/pyproject.toml
+++ b/python/teams/team-one/pyproject.toml
@@ -25,7 +25,9 @@ dependencies = [
     "pyright==1.1.368",
     "mypy==1.10.0",
     "ruff==0.4.8",
-    "pytest"
+    "pytest",
+    "aiofiles",
+    "types-aiofiles"
 ]
 
 [tool.hatch.envs.default.extra-scripts]
diff --git a/python/teams/team-one/src/team_one/agents/coder.py b/python/teams/team-one/src/team_one/agents/coder.py
index 0a3ad612b..8c3b60e62 100644
--- a/python/teams/team-one/src/team_one/agents/coder.py
+++ b/python/teams/team-one/src/team_one/agents/coder.py
@@ -75,8 +75,9 @@ class Coder(TypeRoutedAgent):
 
         # Keep executing the tools until the response is not a list of function calls.
         while isinstance(response.content, list) and all(isinstance(item, FunctionCall) for item in response.content):
+            # TODO: gather internally too
             results = await asyncio.gather(
-                *[self.send_message(ToolMessage(function_call=call), self.id) for call in response.content]
+                *[await self.send_message(ToolMessage(function_call=call), self.id) for call in response.content]
             )
             # Combine the results into a single response.
             result = FunctionExecutionResultMessage(content=[result.result for result in results])
diff --git a/python/teams/team-one/src/team_one/agents/file_surfer.py b/python/teams/team-one/src/team_one/agents/file_surfer.py
index 25120d658..6bb801f51 100644
--- a/python/teams/team-one/src/team_one/agents/file_surfer.py
+++ b/python/teams/team-one/src/team_one/agents/file_surfer.py
@@ -103,8 +103,9 @@ class FileSurfer(TypeRoutedAgent):
 
         # Keep executing the tools until the response is not a list of function calls.
         while isinstance(response.content, list) and all(isinstance(item, FunctionCall) for item in response.content):
+            # TODO: gather internally too
             results = await asyncio.gather(
-                *[self.send_message(ToolMessage(function_call=call), self.id) for call in response.content]
+                *[await self.send_message(ToolMessage(function_call=call), self.id) for call in response.content]
             )
             # Combine the results into a single response.
             result = FunctionExecutionResultMessage(content=[result.result for result in results])
diff --git a/python/tests/test_cancellation.py b/python/tests/test_cancellation.py
index b17f35d04..00aad064d 100644
--- a/python/tests/test_cancellation.py
+++ b/python/tests/test_cancellation.py
@@ -43,7 +43,7 @@ class NestingLongRunningAgent(TypeRoutedAgent):
     @message_handler
     async def on_new_message(self, message: MessageType, cancellation_token: CancellationToken) -> MessageType:
         self.called = True
-        response = self.send_message(message, self._nested_agent, cancellation_token=cancellation_token)
+        response = await self.send_message(message, self._nested_agent, cancellation_token=cancellation_token)
         try:
             val = await response
             assert isinstance(val, MessageType)
@@ -59,7 +59,7 @@ async def test_cancellation_with_token() -> None:
 
     long_running = runtime.register_and_get("long_running", LongRunningAgent)
     token = CancellationToken()
-    response = runtime.send_message(MessageType(), recipient=long_running, cancellation_token=token)
+    response = await runtime.send_message(MessageType(), recipient=long_running, cancellation_token=token)
     assert not response.done()
 
     await runtime.process_next()
@@ -83,7 +83,7 @@ async def test_nested_cancellation_only_outer_called() -> None:
     nested = runtime.register_and_get("nested", lambda: NestingLongRunningAgent(long_running))
 
     token = CancellationToken()
-    response = runtime.send_message(MessageType(), nested, cancellation_token=token)
+    response = await runtime.send_message(MessageType(), nested, cancellation_token=token)
     assert not response.done()
 
     await runtime.process_next()
@@ -108,7 +108,7 @@ async def test_nested_cancellation_inner_called() -> None:
     nested = runtime.register_and_get("nested", lambda: NestingLongRunningAgent(long_running))
 
     token = CancellationToken()
-    response = runtime.send_message(MessageType(), nested, cancellation_token=token)
+    response = await runtime.send_message(MessageType(), nested, cancellation_token=token)
     assert not response.done()
 
     await runtime.process_next()
diff --git a/python/tests/test_intervention.py b/python/tests/test_intervention.py
index 88e673528..8f29dd1ac 100644
--- a/python/tests/test_intervention.py
+++ b/python/tests/test_intervention.py
@@ -21,7 +21,7 @@ async def test_intervention_count_messages() -> None:
     runtime = SingleThreadedAgentRuntime(intervention_handler=handler)
     loopback = runtime.register_and_get("name", LoopbackAgent)
 
-    response = runtime.send_message(MessageType(), recipient=loopback)
+    response = await runtime.send_message(MessageType(), recipient=loopback)
 
     while not response.done():
         await runtime.process_next()
@@ -41,7 +41,7 @@ async def test_intervention_drop_send() -> None:
     runtime = SingleThreadedAgentRuntime(intervention_handler=handler)
 
     loopback = runtime.register_and_get("name", LoopbackAgent)
-    response = runtime.send_message(MessageType(), recipient=loopback)
+    response = await runtime.send_message(MessageType(), recipient=loopback)
 
     while not response.done():
         await runtime.process_next()
@@ -64,7 +64,7 @@ async def test_intervention_drop_response() -> None:
     runtime = SingleThreadedAgentRuntime(intervention_handler=handler)
 
     loopback = runtime.register_and_get("name", LoopbackAgent)
-    response = runtime.send_message(MessageType(), recipient=loopback)
+    response = await runtime.send_message(MessageType(), recipient=loopback)
 
     while not response.done():
         await runtime.process_next()
@@ -87,7 +87,7 @@ async def test_intervention_raise_exception_on_send() -> None:
     runtime = SingleThreadedAgentRuntime(intervention_handler=handler)
 
     long_running = runtime.register_and_get("name", LoopbackAgent)
-    response = runtime.send_message(MessageType(), recipient=long_running)
+    response = await runtime.send_message(MessageType(), recipient=long_running)
 
     while not response.done():
         await runtime.process_next()
@@ -112,7 +112,7 @@ async def test_intervention_raise_exception_on_respond() -> None:
     runtime = SingleThreadedAgentRuntime(intervention_handler=handler)
 
     long_running = runtime.register_and_get("name", LoopbackAgent)
-    response = runtime.send_message(MessageType(), recipient=long_running)
+    response = await runtime.send_message(MessageType(), recipient=long_running)
 
     while not response.done():
         await runtime.process_next()