fix: emit completed tool events after interruption

livekit-agents/livekit/agents/voice/agent_activity.py

@@ -3494,6 +3494,13 @@ async def _next_segment() -> _SpeechSegment | None:
                     interrupted_fnc_outputs.append(sanitized_out.fnc_call_out)
 
             if interrupted_tool_messages := interrupted_calls + interrupted_fnc_outputs:
+                self._session.emit(
+                    "function_tools_executed",
+                    FunctionToolsExecutedEvent(
+                        function_calls=interrupted_calls,
+                        function_call_outputs=interrupted_fnc_outputs,
+                    ),
+                )
                 self._agent._chat_ctx.insert(interrupted_tool_messages)
                 self._session._tool_items_added(interrupted_tool_messages)
             return

tests/test_tool_results_preserved_on_interruption.py

@@ -13,6 +13,7 @@
 from livekit.agents import Agent, AgentSession, function_tool
 from livekit.agents.llm import FunctionToolCall
 from livekit.agents.voice.agent_activity import AgentActivity
+from livekit.agents.voice.events import FunctionToolsExecutedEvent
 from livekit.agents.voice.speech_handle import SpeechHandle
 
 from .fake_session import FakeActions, create_session, run_session
@@ -116,19 +117,40 @@ def _interrupt_after_forced_schedule(
 
 
 async def test_tool_results_preserved_when_interrupted_during_playout() -> None:
-    """Interruption lands while the agent is still speaking the tool turn."""
+    """Completed tool results stay observable when their parent speech is interrupted."""
     actions = FakeActions()
     _weather_tool_turn(actions, tts_duration=10.0)  # playout 3.5s -> 13.5s
     actions.add_user_speech(5.0, 6.0, "Stop!", stt_delay=0.2)  # interrupts at 5.5s
     actions.add_llm(content="Okay, stopping.")
     actions.add_tts(1.0)
+    actions.add_tts(1.0, input="The weather in Tokyo is sunny today.")
 
     session = create_session(actions)
     agent = WeatherAgent()  # the tool completes at ~3.4s, before the interruption
+    tool_executed_events: list[FunctionToolsExecutedEvent] = []
+    tool_speeches: list[SpeechHandle] = []
+
+    def on_function_tools_executed(event: FunctionToolsExecutedEvent) -> None:
+        tool_executed_events.append(event)
+        output = event.function_call_outputs[0]
+        if output is not None:
+            tool_speeches.append(session.say(output.output, allow_interruptions=False))
+
+    session.on("function_tools_executed", on_function_tools_executed)
 
     await asyncio.wait_for(run_session(session, agent), timeout=SESSION_TIMEOUT)
 
     _assert_weather_tool_preserved(agent, session)
+    assert len(tool_executed_events) == 1
+    event = tool_executed_events[0]
+    assert event.function_calls[0].name == "get_weather"
+    output = event.function_call_outputs[0]
+    assert output is not None
+    assert output.output == "The weather in Tokyo is sunny today."
+    assert len(tool_speeches) == 1
+    assert tool_speeches[0].done()
+    assert not tool_speeches[0].interrupted
+    assert not tool_speeches[0].allow_interruptions
 
 
 async def test_tool_results_preserved_when_tool_in_flight_at_interruption() -> None:
@@ -175,8 +197,11 @@ async def transfer_to_billing(self) -> Agent:
 
     session = create_session(actions)
     agent = TransferAgent()
+    tool_executed_events: list[FunctionToolsExecutedEvent] = []
+    session.on("function_tools_executed", tool_executed_events.append)
 
     await asyncio.wait_for(run_session(session, agent), timeout=SESSION_TIMEOUT)
 
+    assert not tool_executed_events
     for items in (agent.chat_ctx.items, session.history.items):
         assert not any(i.type in ("function_call", "function_call_output") for i in items)