From 3e5e89e265aaa33580d0cc5dbe6891f5d36a7c5f Mon Sep 17 00:00:00 2001
From: Patrick Gray <pgrayy@amazon.com>
Date: Tue, 29 Sep 2026 12:06:47 -0400
Subject: [PATCH] feat(bidi): support cancellation from custom tools (#4664)

---
 .../sdk/bidirectional-streaming/agent.mdx     |   4 +-
 .../sdk/bidirectional-streaming/events.mdx    |   3 +-
 .../sdk/bidirectional-streaming/io.mdx        |  16 +-
 .../models/bedrock.mdx                        |   3 +-
 .../bidirectional-streaming/models/google.mdx |   4 +-
 .../bidirectional-streaming/models/openai.mdx |   4 +-
 .../bidirectional-streaming/quickstart.mdx    |  34 ++--
 .../src/strands/experimental/bidi/__init__.py |   4 +-
 .../strands/experimental/bidi/agent/agent.py  |  19 +-
 .../strands/experimental/bidi/agent/loop.py   |  26 +--
 .../experimental/bidi/tools/__init__.py       |  18 --
 .../bidi/tools/stop_conversation.py           |  32 ----
 .../src/strands/tools/executors/_executor.py  |   2 +-
 strands-py/src/strands/types/agent.py         |   4 +
 .../strands/agent/test_agent_cancellation.py  |   4 +-
 .../experimental/bidi/agent/test_agent.py     |  38 +++-
 .../experimental/bidi/agent/test_loop.py      | 170 +++++++-----------
 strands-py/tests_typing/test_local_agent.py   |   3 +-
 18 files changed, 160 insertions(+), 228 deletions(-)
 delete mode 100644 strands-py/src/strands/experimental/bidi/tools/__init__.py
 delete mode 100644 strands-py/src/strands/experimental/bidi/tools/stop_conversation.py

diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/agent.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/agent.mdx
index f23bf7752..b1821de42 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/agent.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/agent.mdx
@@ -177,7 +177,9 @@ Each grouped tool-use message stays adjacent to its matching result message, eve
 
 Tool-result messages use `metadata["custom"]["bidi"]["kind"]` to distinguish `tool_dispatch` acknowledgements from `tool_result` messages.
 
-After the group finishes, the agent loop checks `request_state["stop_event_loop"]` to trigger graceful shutdown instead of sending tool results back to the model. Any tool can set this flag to stop the conversation. The SDK's experimental `stop` tool uses this mechanism.
+To let a tool end the conversation, call `tool_context.agent.cancel()`. Cancellation takes effect only after the tool group completes. Requests from other contexts remain pending until then.
+
+See [Graceful shutdown](./quickstart.mdx#graceful-shutdown) for a custom tool example.
 
 ### Connection Lifecycle
 
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/events.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/events.mdx
index 0c65aa29d..d1eb5a4b7 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/events.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/events.mdx
@@ -225,8 +225,7 @@ Emitted when the streaming connection is closed.
   - `"timeout"`: Connection timed out
   - `"error"`: Error occurred
   - `"complete"`: Conversation completed normally
-  - `"user_request"`: User requested closure (via the SDK's experimental `stop`
-    tool or any tool that sets `request_state["stop_event_loop"]`)
+  - `"user_request"`: Cancellation requested through `agent.cancel()`
 
 ### Response Lifecycle Events
 
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/io.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/io.mdx
index 4c741f513..524b9651e 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/io.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/io.mdx
@@ -88,12 +88,10 @@ Pass your I/O streams to the agent's `run()` method to connect them to the agent
 import asyncio
 
 from strands.experimental.bidi.agent import BidiAgent
-from strands.experimental.tools import stop
 
 
 async def main():
-    # stop tool allows user to verbally stop agent execution.
-    agent = BidiAgent(tools=[stop])
+    agent = BidiAgent()
     await agent.run(inputs=[MyInputStream()], outputs=[MyOutputStream()])
 
 
@@ -104,6 +102,8 @@ The `run()` method handles startup, execution, and shutdown for the agent and it
 streams. Inputs and outputs run concurrently, so you can mix and match implementations.
 If an I/O task fails, `run()` cancels the remaining tasks, stops the streams, and
 re-raises the exception.
+For a tool that lets users end the conversation, see
+[Graceful shutdown](./quickstart.mdx#graceful-shutdown).
 
 ## Audio I/O
 
@@ -126,12 +126,10 @@ import asyncio
 
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO
-from strands.experimental.tools import stop
 
 
 async def main():
-    # stop tool allows user to verbally stop agent execution.
-    agent = BidiAgent(tools=[stop])
+    agent = BidiAgent()
     audio_io = AudioIO(input_device_index=1)
 
     await agent.run(
@@ -232,7 +230,6 @@ import asyncio
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import ConsoleIO
 from strands.experimental.bidi.models import OpenAIRealtimeModel
-from strands.experimental.tools import stop
 
 
 async def main():
@@ -241,7 +238,7 @@ async def main():
         transcription_model_id=None,
         params={"output_modalities": ["text"]},
     )
-    agent = BidiAgent(model=model, tools=[stop])
+    agent = BidiAgent(model=model)
     console_io = ConsoleIO()
 
     await agent.run(
@@ -280,11 +277,10 @@ import asyncio
 
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO, ConsoleIO
-from strands.experimental.tools import stop
 
 
 async def main():
-    agent = BidiAgent(tools=[stop])
+    agent = BidiAgent()
     console_io = ConsoleIO(placeholder="Type or speak…")
     audio_io = AudioIO(console=console_io)
 
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/bedrock.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/bedrock.mdx
index 6bcc76eec..c22870aaf 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/bedrock.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/bedrock.mdx
@@ -49,7 +49,6 @@ import asyncio
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO
 from strands.experimental.bidi.models import BedrockNovaSonicModel
-from strands.experimental.tools import stop
 from strands.vended_tools import notebook
 
 
@@ -59,7 +58,7 @@ async def main() -> None:
         region="us-east-1",
         voice="tiffany",
     )
-    agent = BidiAgent(model=model, tools=[notebook, stop])
+    agent = BidiAgent(model=model, tools=[notebook])
     audio_io = AudioIO()
     await agent.run(inputs=[audio_io.input()], outputs=[audio_io.output()])
 
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/google.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/google.mdx
index 87314d351..09d460af3 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/google.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/google.mdx
@@ -45,7 +45,6 @@ import asyncio
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO
 from strands.experimental.bidi.models import GoogleGeminiLiveModel
-from strands.experimental.tools import stop
 from strands.vended_tools import notebook
 
 
@@ -55,8 +54,7 @@ async def main() -> None:
         voice="Kore",
         client_args={"api_key": "<GOOGLE_API_KEY>"},
     )
-    # stop tool allows user to verbally stop agent execution.
-    agent = BidiAgent(model=model, tools=[notebook, stop])
+    agent = BidiAgent(model=model, tools=[notebook])
 
     audio_io = AudioIO()
     await agent.run(inputs=[audio_io.input()], outputs=[audio_io.output()])
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/openai.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/openai.mdx
index 46c3096e6..bd900544d 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/openai.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/models/openai.mdx
@@ -44,7 +44,6 @@ import asyncio
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO
 from strands.experimental.bidi.models import OpenAIRealtimeModel
-from strands.experimental.tools import stop
 from strands.vended_tools import notebook
 
 
@@ -55,8 +54,7 @@ async def main() -> None:
         voice="coral",
         api_key="<OPENAI_API_KEY>",
     )
-    # stop tool allows user to verbally stop agent execution.
-    agent = BidiAgent(model=model, tools=[notebook, stop])
+    agent = BidiAgent(model=model, tools=[notebook])
 
     audio_io = AudioIO()
     await agent.run(inputs=[audio_io.input()], outputs=[audio_io.output()])
diff --git a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/quickstart.mdx b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/quickstart.mdx
index 0ac985195..5e4ebfb02 100644
--- a/site/src/content/docs/user-guide/sdk/bidirectional-streaming/quickstart.mdx
+++ b/site/src/content/docs/user-guide/sdk/bidirectional-streaming/quickstart.mdx
@@ -406,22 +406,28 @@ See [Controlling Conversation Lifecycle](#controlling-conversation-lifecycle) fo
 
 ## Graceful Shutdown
 
-Use the SDK's experimental `stop` tool to allow users to end conversations
-naturally. It sets `request_state["stop_event_loop"]`, which the agent loop checks
-to trigger a graceful shutdown:
+To let users end a conversation by voice, define a tool that calls `agent.cancel()`:
 
 ```python
 import asyncio
+from strands import LocalAgent, ToolContext, tool
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.io import AudioIO
 from strands.experimental.bidi.models import BedrockNovaSonicModel
-from strands.experimental.tools import stop
+
+
+@tool(context=True)
+def end_conversation(tool_context: ToolContext[LocalAgent]) -> str:
+    """End the conversation when the user asks to stop."""
+    tool_context.agent.cancel()
+    return "Ending conversation"
+
 
 model = BedrockNovaSonicModel(model_id="amazon.nova-2-sonic-v1:0")
 agent = BidiAgent(
     model=model,
-    tools=[stop],
-    system_prompt="You are a helpful assistant. When the user says 'stop conversation', use the stop tool."
+    tools=[end_conversation],
+    system_prompt="You are a helpful assistant.",
 )
 
 audio_io = AudioIO()
@@ -431,24 +437,12 @@ async def main():
         inputs=[audio_io.input()],
         outputs=[audio_io.output()]
     )
-    # Conversation ends when user says "stop conversation"
+    # run() returns after the agent calls end_conversation.
 
 asyncio.run(main())
 ```
 
-You can also create custom stop tools using the `request_state["stop_event_loop"]` flag:
-
-```python
-from strands import tool
-
-@tool
-def end_session(request_state: dict) -> str:
-    request_state["stop_event_loop"] = True
-    return "Goodbye!"
-```
-
-The agent will gracefully close the connection when any tool sets `request_state["stop_event_loop"] = True`.
-
+Bidi checks for cancellation after a tool group completes and its results are recorded. Requests from other contexts remain pending until that checkpoint.
 
 ## Debug Logs
 
diff --git a/strands-py/src/strands/experimental/bidi/__init__.py b/strands-py/src/strands/experimental/bidi/__init__.py
index 06c814e19..62c6134a4 100644
--- a/strands-py/src/strands/experimental/bidi/__init__.py
+++ b/strands-py/src/strands/experimental/bidi/__init__.py
@@ -1,7 +1,7 @@
 """Experimental bidirectional streaming APIs."""
 
-from . import agent, hooks, io, models, tools, types
+from . import agent, hooks, io, models, types
 from .agent import BidiAgent as BidiAgent
 
 # Compatibility for AgentCore's root import; remove after AgentCore imports from bidi.agent.
-__all__ = ["agent", "hooks", "io", "models", "tools", "types"]
+__all__ = ["agent", "hooks", "io", "models", "types"]
diff --git a/strands-py/src/strands/experimental/bidi/agent/agent.py b/strands-py/src/strands/experimental/bidi/agent/agent.py
index 5d6961504..2b173496f 100644
--- a/strands-py/src/strands/experimental/bidi/agent/agent.py
+++ b/strands-py/src/strands/experimental/bidi/agent/agent.py
@@ -153,7 +153,6 @@ class BidiAgent(LocalAgent):
         self.messages = messages if messages is not None else []
         self._storage: Storage | None = storage
         self._sandbox: Sandbox = NotASandboxLocalEnvironment()
-        # Never set yet: bidirectional agents do not act on a cancellation signal.
         self._cancel_signal = threading.Event()
 
         # Agent identification
@@ -289,9 +288,20 @@ class BidiAgent(LocalAgent):
     def event_loop_metrics(self, value: "EventLoopMetrics") -> None:
         raise NotImplementedError("event_loop_metrics is not supported by bidirectional agents yet")
 
+    def cancel(self) -> None:
+        """Request cancellation of the current conversation.
+
+        This method is thread-safe and idempotent. Cancellation takes effect
+        only after a tool group completes.
+        """
+        self._cancel_signal.set()
+
     @property
     def cancel_signal(self) -> threading.Event:
-        """The cancellation signal; never set yet, because bidirectional agents do not act on it."""
+        """The cancellation signal for the current conversation.
+
+        Treat as read-only; call ``cancel()`` to request cancellation.
+        """
         return self._cancel_signal
 
     def add_hook(
@@ -445,7 +455,10 @@ class BidiAgent(LocalAgent):
         closes the connection to the model provider.
         """
         self._started = False
-        await self._loop.stop()
+        try:
+            await self._loop.stop()
+        finally:
+            self._cancel_signal.clear()
 
     def take_snapshot(
         self,
diff --git a/strands-py/src/strands/experimental/bidi/agent/loop.py b/strands-py/src/strands/experimental/bidi/agent/loop.py
index b22c0e4c7..21dde3603 100644
--- a/strands-py/src/strands/experimental/bidi/agent/loop.py
+++ b/strands-py/src/strands/experimental/bidi/agent/loop.py
@@ -6,7 +6,6 @@ The agent loop handles the events received from the model and executes tools whe
 import asyncio
 import logging
 import time
-import warnings
 from collections.abc import AsyncGenerator
 from dataclasses import dataclass
 from typing import TYPE_CHECKING, Any, Literal, cast
@@ -198,6 +197,8 @@ class _AgentLoop:
         self._model_task = self._task_pool.create(self._run_model(self._generation))
 
         self._invocation_state = invocation_state if invocation_state is not None else {}
+        # Retained for compatibility with shared tools that expect request_state.
+        self._invocation_state.setdefault("request_state", {})
         self._send_gate.set()
         self._started = True
 
@@ -741,7 +742,6 @@ class _AgentLoop:
 
     async def _run_tools(self, tool_uses: list[ToolUse]) -> None:
         """Execute a provider's tool group concurrently and send its results together."""
-        invocation_state = self._invocation_state
         try:
             async with _TaskGroup() as task_group:
                 tasks = [task_group.create_task(self._run_tool(tool_use)) for tool_use in tool_uses]
@@ -759,18 +759,8 @@ class _AgentLoop:
             await self._agent._append_messages(tool_use_message, tool_result_message)
             await self._event_queue.put(ToolResultMessageEvent(tool_result_message))
 
-            should_stop = invocation_state.get("request_state", {}).get("stop_event_loop", False)
-            if not should_stop and any(tool_use["name"] == "stop_conversation" for tool_use in tool_uses):
-                warnings.warn(
-                    "Stopping the event loop by tool name 'stop_conversation' is deprecated. "
-                    "Use request_state['stop_event_loop'] = True instead.",
-                    DeprecationWarning,
-                    stacklevel=2,
-                )
-                should_stop = True
-
-            if should_stop:
-                logger.info("stop_event_loop=<True> | stopping conversation")
+            if self._agent.cancel_signal.is_set():
+                logger.info("cancellation requested | stopping conversation")
                 connection_id = getattr(self._agent.model, "_connection_id", "unknown")
                 await self._event_queue.put(BidiConnectionStopEvent(connection_id=connection_id, reason="user_request"))
                 return
@@ -803,11 +793,6 @@ class _AgentLoop:
 
         tool_results: list[ToolResult] = []
 
-        # Ensure request_state exists for tools like strands_tools.stop
-        invocation_state = self._invocation_state
-        if "request_state" not in invocation_state:
-            invocation_state["request_state"] = {}
-
         tool_call_span = self._tracer.start_tool_call_span(tool_use, parent_span=self._session_span)
         tool_result: ToolResult | None = None
         tool_error: Exception | None = None
@@ -817,7 +802,7 @@ class _AgentLoop:
                 self._agent,
                 tool_use,
                 tool_results,
-                invocation_state,
+                self._invocation_state,
                 structured_output_context=None,
             )
 
@@ -829,7 +814,6 @@ class _AgentLoop:
 
                 await self._event_queue.put(tool_event)
 
-            # Normal flow for all tools (including stop_conversation)
             tool_result_event = cast(ToolResultEvent, tool_event)
             tool_result = tool_result_event.tool_result
 
diff --git a/strands-py/src/strands/experimental/bidi/tools/__init__.py b/strands-py/src/strands/experimental/bidi/tools/__init__.py
deleted file mode 100644
index de67040de..000000000
--- a/strands-py/src/strands/experimental/bidi/tools/__init__.py
+++ /dev/null
@@ -1,18 +0,0 @@
-"""Built-in tools for bidirectional agents.
-
-.. deprecated::
-    The built-in ``stop_conversation`` tool is deprecated. Use ``strands_tools.stop`` or set
-    ``request_state["stop_event_loop"] = True`` in any custom tool instead.
-
-To stop a bidirectional conversation, use the standard ``stop`` tool from strands_tools::
-
-    from strands_tools import stop
-    agent = BidiAgent(tools=[stop, ...])
-
-The stop tool sets ``request_state["stop_event_loop"] = True``, which signals the
-BidiAgent to gracefully close the connection.
-"""
-
-from .stop_conversation import stop_conversation
-
-__all__ = ["stop_conversation"]
diff --git a/strands-py/src/strands/experimental/bidi/tools/stop_conversation.py b/strands-py/src/strands/experimental/bidi/tools/stop_conversation.py
deleted file mode 100644
index 21b530552..000000000
--- a/strands-py/src/strands/experimental/bidi/tools/stop_conversation.py
+++ /dev/null
@@ -1,32 +0,0 @@
-"""Tool to gracefully stop a bidirectional connection.
-
-.. deprecated::
-    The ``stop_conversation`` tool is deprecated and will be removed in a future version.
-    Use ``strands_tools.stop`` or set ``request_state["stop_event_loop"] = True`` in any custom tool instead.
-"""
-
-import warnings
-
-from ....tools.decorator import tool
-
-
-@tool
-def stop_conversation() -> str:
-    """Stop the bidirectional conversation gracefully.
-
-    .. deprecated::
-        Use ``strands_tools.stop`` or set ``request_state["stop_event_loop"] = True`` in a custom tool instead.
-
-    Use ONLY when user says "stop conversation" exactly.
-    Do NOT use for: "stop", "goodbye", "bye", "exit", "quit", "end" or other farewells or phrases.
-
-    Returns:
-        Success message confirming the conversation will end.
-    """
-    warnings.warn(
-        "stop_conversation is deprecated and will be removed in a future version. "
-        "Use strands_tools.stop or set request_state['stop_event_loop'] = True in any custom tool instead.",
-        DeprecationWarning,
-        stacklevel=2,
-    )
-    return "Ending conversation"
diff --git a/strands-py/src/strands/tools/executors/_executor.py b/strands-py/src/strands/tools/executors/_executor.py
index 0c376433f..16008258d 100644
--- a/strands-py/src/strands/tools/executors/_executor.py
+++ b/strands-py/src/strands/tools/executors/_executor.py
@@ -58,7 +58,7 @@ class ToolExecutor(abc.ABC):
         if cast(dict[str, Any], after_event.result).get("cancelled") is True:
             return False
         if not ToolExecutor._is_agent(agent):
-            return True
+            return not agent.cancel_signal.is_set()
         return not cast("Agent", agent)._observe_cancellation()
 
     async def _execute_background(
diff --git a/strands-py/src/strands/types/agent.py b/strands-py/src/strands/types/agent.py
index ebbbc1f1b..5868ca8f0 100644
--- a/strands-py/src/strands/types/agent.py
+++ b/strands-py/src/strands/types/agent.py
@@ -104,6 +104,10 @@ class LocalAgent(Protocol):
         """The cancellation signal for the current invocation."""
         ...
 
+    def cancel(self) -> None:
+        """Request cancellation at the agent's next supported checkpoint."""
+        ...
+
     def add_hook(
         self,
         callback: HookCallback[_TEvent],
diff --git a/strands-py/tests/strands/agent/test_agent_cancellation.py b/strands-py/tests/strands/agent/test_agent_cancellation.py
index dcf3a760a..4d63355df 100644
--- a/strands-py/tests/strands/agent/test_agent_cancellation.py
+++ b/strands-py/tests/strands/agent/test_agent_cancellation.py
@@ -7,7 +7,7 @@ from unittest.mock import ANY
 
 import pytest
 
-from strands import Agent, tool
+from strands import Agent, LocalAgent, ToolContext, tool
 from strands.hooks import AfterModelCallEvent, BeforeModelCallEvent, BeforeToolCallEvent, BeforeToolsEvent
 from tests.fixtures.mocked_model_provider import MockedModelProvider
 
@@ -575,7 +575,7 @@ async def test_hook_cancelled_tool_batch_does_not_replay_the_stored_tool_use():
 
 def _approver_agent(ran, cancel_on_first_run=False):
     @tool(context=True)
-    def approver(tool_context) -> str:
+    def approver(tool_context: ToolContext[LocalAgent]) -> str:
         """Require approval before doing the work."""
         tool_context.interrupt("approve", reason="proceed?")
         ran.append("executed")
diff --git a/strands-py/tests/strands/experimental/bidi/agent/test_agent.py b/strands-py/tests/strands/experimental/bidi/agent/test_agent.py
index 2bdfff21d..3a4d2d559 100644
--- a/strands-py/tests/strands/experimental/bidi/agent/test_agent.py
+++ b/strands-py/tests/strands/experimental/bidi/agent/test_agent.py
@@ -2,7 +2,6 @@
 
 import asyncio
 import sys
-import threading
 import unittest.mock
 from contextlib import nullcontext
 from uuid import uuid4
@@ -18,6 +17,7 @@ from strands.experimental.bidi.types import (
     BidiConnectionStartEvent,
     BidiConnectionStopEvent,
     BidiMessage,
+    BidiToolUseBlocksEvent,
     BidiTranscriptDeltaEvent,
     BidiTranscriptStartEvent,
     InputStream,
@@ -313,12 +313,40 @@ def test_bidi_agent_sandbox_defaults_to_host_environment(mock_model):
     assert agent.sandbox is agent.sandbox
 
 
-def test_bidi_agent_cancel_signal_is_never_set(mock_model):
+def test_cancel_sets_signal(mock_model):
     agent = BidiAgent(model=mock_model)
+    signal = agent.cancel_signal
 
-    assert isinstance(agent.cancel_signal, threading.Event)
-    assert not agent.cancel_signal.is_set()
-    assert agent.cancel_signal is agent.cancel_signal
+    assert not signal.is_set()
+
+    agent.cancel()
+    agent.cancel()
+
+    assert signal.is_set()
+
+
+@pytest.mark.asyncio
+async def test_run_cancel_cleans_up_and_allows_reuse(mock_model):
+    @tool(context=True)
+    def end_conversation(tool_context: ToolContext[LocalAgent]) -> str:
+        """End the conversation."""
+        tool_context.agent.cancel()
+        return "Ending conversation"
+
+    mock_model.set_events(
+        [BidiToolUseBlocksEvent([{"toolUseId": "end", "name": end_conversation.tool_name, "input": {}}])]
+    )
+    agent = BidiAgent(model=mock_model, tools=[end_conversation])
+
+    for _ in range(2):
+        input_ = unittest.mock.AsyncMock(spec=InputStream, side_effect=asyncio.Queue().get)
+        output = unittest.mock.AsyncMock(spec=OutputStream)
+        await asyncio.wait_for(agent.run(inputs=[input_], outputs=[output]), 2)
+
+        input_.stop.assert_awaited_once()
+        output.stop.assert_awaited_once()
+        assert not agent.cancel_signal.is_set()
+        assert not mock_model._started
 
 
 def test_bidi_agent_tool_context_receives_cancel_signal(mock_model):
diff --git a/strands-py/tests/strands/experimental/bidi/agent/test_loop.py b/strands-py/tests/strands/experimental/bidi/agent/test_loop.py
index 525930ee7..3acef72c0 100644
--- a/strands-py/tests/strands/experimental/bidi/agent/test_loop.py
+++ b/strands-py/tests/strands/experimental/bidi/agent/test_loop.py
@@ -1,11 +1,10 @@
 import asyncio
 import unittest.mock
-import warnings
 
 import pytest
 import pytest_asyncio
 
-from strands import ToolContext, tool
+from strands import LocalAgent, ToolContext, tool
 from strands.experimental.bidi.agent import BidiAgent
 from strands.experimental.bidi.agent.loop import _ReaderError
 from strands.experimental.bidi.hooks import BidiAgentStopEvent, BidiBeforeConnectionRestartEvent
@@ -1869,120 +1868,87 @@ async def test_tool_exchanges_remain_paired_when_results_finish_out_of_order(str
 
 
 @pytest.mark.asyncio
-async def test_bidi_agent_loop_request_state_initialized_for_tools(loop, agent, agenerator):
-    """Test that request_state is initialized in invocation_state before tool execution.
-
-    This ensures request_state exists for tools that may need it via invocation_state,
-    even when invocation_state is not provided by the user.
-    """
-    tool_use = {"toolUseId": "t2", "name": "time_tool", "input": {}}
-    tool_use_event = BidiToolUseBlocksEvent([tool_use])
-
-    agent.model.receive = unittest.mock.Mock(return_value=agenerator([tool_use_event]))
-
-    # Start without providing invocation_state
-    await loop.start()
-
-    tru_events = []
-    async for event in loop.receive():
-        tru_events.append(event)
-        if len(tru_events) >= 3:
-            break
-
-    # Verify tool executed successfully
-    tool_result_event = tru_events[1]
-    assert isinstance(tool_result_event, ToolResultEvent)
-    assert tool_result_event.tool_result["status"] == "success"
-
-    # Verify request_state was initialized in invocation_state
-    assert "request_state" in loop._invocation_state
-    assert isinstance(loop._invocation_state["request_state"], dict)
-
-
-@pytest.mark.asyncio
+@pytest.mark.parametrize("retry", [False, True])
+@pytest.mark.parametrize("cancel_source", ["tool", "hook"])
 @pytest.mark.parametrize("tool_count", [1, 2])
-async def test_bidi_agent_loop_stop_event_loop_flag(agent, agenerator, alist, tool_count):
-    """Complete the tool group before honoring the stop flag."""
-    loop = agent._loop
-    tool_uses = [{"toolUseId": f"call-{index}", "name": "time_tool", "input": {}} for index in range(tool_count)]
-    tool_use_event = BidiToolUseBlocksEvent(tool_uses)
-    agent.model.receive = unittest.mock.Mock(return_value=agenerator([tool_use_event]))
-    await loop.start(invocation_state={"request_state": {"stop_event_loop": True}})
+async def test_receive_cancel_after_tool(agent, agenerator, alist, retry, cancel_source, tool_count):
+    @tool(context=True)
+    def end_conversation(tool_context: ToolContext[LocalAgent]) -> str:
+        """End the conversation."""
+        if cancel_source == "tool":
+            tool_context.agent.cancel()
+        return "Ending conversation"
 
-    results = [
-        {"toolUseId": call["toolUseId"], "status": "success", "content": [{"text": "12:00"}]} for call in tool_uses
+    def after_tool(event: AfterToolCallEvent[LocalAgent]) -> None:
+        if cancel_source == "hook":
+            event.agent.cancel()
+        event.retry = retry
+
+    agent.tool_registry.register_tool(end_conversation)
+    agent.hooks.add_callback(AfterToolCallEvent, after_tool)
+
+    tool_uses = [
+        {"toolUseId": f"call-{index}", "name": end_conversation.tool_name, "input": {}} for index in range(tool_count)
     ]
-    tru_events = await alist(loop.receive())
+    tool_results = [
+        {"toolUseId": call["toolUseId"], "status": "success", "content": [{"text": "Ending conversation"}]}
+        for call in tool_uses
+    ]
+    tool_use_event = BidiToolUseBlocksEvent(tool_uses)
+
+    agent.model.receive = unittest.mock.Mock(return_value=agenerator([tool_use_event]))
+
+    async with agent:
+        tru_events = await asyncio.wait_for(alist(agent.receive()), 2)
+
+    exp_result_message = {
+        "role": "user",
+        "content": [{"toolResult": tool_result} for tool_result in tool_results],
+        "metadata": {"custom": {"bidi": {"kind": "tool_result"}}},
+        "tracking_id": unittest.mock.ANY,
+    }
     exp_events = [
         tool_use_event,
-        *[ToolResultEvent(result) for result in results],
-        ToolResultMessageEvent(
-            {
-                "role": "user",
-                "content": [{"toolResult": result} for result in results],
-                "metadata": {"custom": {"bidi": {"kind": "tool_result"}}},
-                "tracking_id": unittest.mock.ANY,
-            }
-        ),
-        BidiConnectionStopEvent(connection_id=unittest.mock.ANY, reason="user_request"),
+        *[ToolResultEvent(tool_result) for tool_result in tool_results],
+        ToolResultMessageEvent(exp_result_message),
+        BidiConnectionStopEvent(connection_id="unknown", reason="user_request"),
     ]
     assert tru_events == exp_events
-    agent.model.send.assert_not_awaited()
-
-
-@pytest.mark.asyncio
-async def test_bidi_agent_loop_stop_conversation_deprecated_but_works(loop, agent, agenerator):
-    """Test that stop_conversation tool still works but emits a deprecation warning.
-
-    The stop_conversation tool is deprecated in favor of request_state["stop_event_loop"],
-    but should continue to work for backward compatibility via the name-based check.
-    """
-    from strands.experimental.bidi.tools import stop_conversation
-
-    agent.tool_registry.register_tool(stop_conversation)
-
-    tool_use = {"toolUseId": "t5", "name": "stop_conversation", "input": {}}
-    tool_use_event = BidiToolUseBlocksEvent([tool_use])
-
-    agent.model.receive = unittest.mock.Mock(return_value=agenerator([tool_use_event]))
-
-    await loop.start()
-
-    tru_events = []
-    with warnings.catch_warnings(record=True) as caught_warnings:
-        warnings.simplefilter("always")
-        async for event in loop.receive():
-            tru_events.append(event)
-
-    # Should receive: tool_use_event, tool_result_event, tool_result_message, connection_stop
-    assert len(tru_events) == 4
-
-    # Verify tool executed successfully
-    tool_result_event = tru_events[1]
-    assert isinstance(tool_result_event, ToolResultEvent)
-    assert tool_result_event.tool_result["status"] == "success"
-    assert "Ending conversation" in tool_result_event.tool_result["content"][0]["text"]
-
-    # Verify connection stop event was emitted
-    connection_stop_event = tru_events[3]
-    assert isinstance(connection_stop_event, BidiConnectionStopEvent)
-    assert connection_stop_event["reason"] == "user_request"
-
-    # Verify model.send was NOT called (tool result not sent to model)
+    assert agent.messages[-1] == exp_result_message
     agent.model.send.assert_not_called()
 
-    # Verify deprecation warnings were emitted (from both the tool itself and the loop name check)
-    deprecation_warnings = [w for w in caught_warnings if issubclass(w.category, DeprecationWarning)]
-    assert len(deprecation_warnings) >= 1
-    assert any("stop_conversation" in str(w.message).lower() for w in deprecation_warnings)
+
+@pytest.mark.asyncio
+async def test_receive_cancel_pending_until_tool_completes(streaming_agent, alist):
+    agent = streaming_agent
+    request = BidiToolUseBlocksEvent([{"toolUseId": "time", "name": "time_tool", "input": {}}])
+    audio = BidiAudioDeltaEvent("audio", "pcm", 24000, 1, content_id="audio")
+    reader = agent.receive()
+    try:
+        agent.cancel()
+        await agent.model.emit(audio)
+        assert await asyncio.wait_for(anext(reader), 2) == audio
+
+        await agent.model.emit(request)
+        tru_events = await asyncio.wait_for(alist(reader), 2)
+    finally:
+        await reader.aclose()
+
+    assert [type(event) for event in tru_events] == [
+        BidiToolUseBlocksEvent,
+        ToolResultEvent,
+        ToolResultMessageEvent,
+        BidiConnectionStopEvent,
+    ]
 
 
 @pytest.mark.asyncio
-@pytest.mark.parametrize("invocation_state", [{}, {"custom_data": "preserved"}])
+@pytest.mark.parametrize(
+    "invocation_state", [{}, {"custom_data": "preserved"}, {"request_state": {"custom_data": "preserved"}}]
+)
 async def test_tools_share_invocation_state(agent, agenerator, invocation_state):
     """Tools, hooks, and the caller share state throughout the invocation."""
-    invocation_state = dict(invocation_state)
-    exp_state = {**invocation_state, "call_count": 2, "request_state": {}}
+    exp_state = {"request_state": {}, **invocation_state, "call_count": 2}
     tool_states = []
 
     @tool(context=True)
diff --git a/strands-py/tests_typing/test_local_agent.py b/strands-py/tests_typing/test_local_agent.py
index 7ac68aea0..5651eea32 100644
--- a/strands-py/tests_typing/test_local_agent.py
+++ b/strands-py/tests_typing/test_local_agent.py
@@ -32,6 +32,7 @@ def agent_tool(tool_context: ToolContext[Agent]) -> str:
 @tool(context=True)
 def local_agent_tool(tool_context: ToolContext[LocalAgent]) -> str:
     assert_type(tool_context.agent, LocalAgent)
+    tool_context.agent.cancel()
     return tool_context.agent.name
 
 
@@ -41,6 +42,7 @@ def before_tool_call(event: BeforeToolCallEvent) -> None:
 
 def before_local_tool_call(event: BeforeToolCallEvent[LocalAgent]) -> None:
     assert_type(event.agent, LocalAgent)
+    event.agent.cancel()
 
 
 async def after_local_tool_call(event: AfterToolCallEvent[LocalAgent]) -> None:
@@ -100,7 +102,6 @@ def register_hooks(agent: Agent, bidi_agent: BidiAgent, local_agent: LocalAgent)
 
 def local_agent_excludes_agent_only_members(local_agent: LocalAgent) -> None:
     local_agent.cleanup()  # type: ignore[attr-defined]
-    local_agent.cancel()  # type: ignore[attr-defined]
     local_agent.conversation_manager  # type: ignore[attr-defined]  # noqa: B018
     local_agent.tool_executor  # type: ignore[attr-defined]  # noqa: B018