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Openai Realtime

OpenAIRealtimeWebSocketModel

Bases: RealtimeModel

A model that uses OpenAI's WebSocket API.

Source code in src/agents/realtime/openai_realtime.py
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class OpenAIRealtimeWebSocketModel(RealtimeModel):
    """A model that uses OpenAI's WebSocket API."""

    def __init__(self) -> None:
        self.model = "gpt-realtime"  # Default model
        self._websocket: ClientConnection | None = None
        self._websocket_task: asyncio.Task[None] | None = None
        self._listeners: list[RealtimeModelListener] = []
        self._current_item_id: str | None = None
        self._audio_state_tracker: ModelAudioTracker = ModelAudioTracker()
        self._ongoing_response: bool = False
        self._tracing_config: RealtimeModelTracingConfig | Literal["auto"] | None = None
        self._playback_tracker: RealtimePlaybackTracker | None = None
        self._created_session: OpenAISessionCreateRequest | None = None
        self._server_event_type_adapter = get_server_event_type_adapter()
        self._call_id: str | None = None

    async def connect(self, options: RealtimeModelConfig) -> None:
        """Establish a connection to the model and keep it alive."""
        assert self._websocket is None, "Already connected"
        assert self._websocket_task is None, "Already connected"

        model_settings: RealtimeSessionModelSettings = options.get("initial_model_settings", {})

        self._playback_tracker = options.get("playback_tracker", None)

        call_id = options.get("call_id")
        model_name = model_settings.get("model_name")
        if call_id and model_name:
            error_message = (
                "Cannot specify both `call_id` and `model_name` "
                "when attaching to an existing realtime call."
            )
            raise UserError(error_message)

        if model_name:
            self.model = model_name

        self._call_id = call_id
        api_key = await get_api_key(options.get("api_key"))

        if "tracing" in model_settings:
            self._tracing_config = model_settings["tracing"]
        else:
            self._tracing_config = "auto"

        if call_id:
            url = options.get("url", f"wss://api.openai.com/v1/realtime?call_id={call_id}")
        else:
            url = options.get("url", f"wss://api.openai.com/v1/realtime?model={self.model}")

        headers: dict[str, str] = {}
        if options.get("headers") is not None:
            # For customizing request headers
            headers.update(options["headers"])
        else:
            # OpenAI's Realtime API
            if not api_key:
                raise UserError("API key is required but was not provided.")

            headers.update({"Authorization": f"Bearer {api_key}"})
        self._websocket = await websockets.connect(
            url,
            user_agent_header=_USER_AGENT,
            additional_headers=headers,
            max_size=None,  # Allow any size of message
        )
        self._websocket_task = asyncio.create_task(self._listen_for_messages())
        await self._update_session_config(model_settings)

    async def _send_tracing_config(
        self, tracing_config: RealtimeModelTracingConfig | Literal["auto"] | None
    ) -> None:
        """Update tracing configuration via session.update event."""
        if tracing_config is not None:
            converted_tracing_config = _ConversionHelper.convert_tracing_config(tracing_config)
            await self._send_raw_message(
                OpenAISessionUpdateEvent(
                    session=OpenAISessionCreateRequest(
                        model=self.model,
                        type="realtime",
                        tracing=converted_tracing_config,
                    ),
                    type="session.update",
                )
            )

    def add_listener(self, listener: RealtimeModelListener) -> None:
        """Add a listener to the model."""
        if listener not in self._listeners:
            self._listeners.append(listener)

    def remove_listener(self, listener: RealtimeModelListener) -> None:
        """Remove a listener from the model."""
        if listener in self._listeners:
            self._listeners.remove(listener)

    async def _emit_event(self, event: RealtimeModelEvent) -> None:
        """Emit an event to the listeners."""
        # Copy list to avoid modification during iteration
        for listener in list(self._listeners):
            await listener.on_event(event)

    async def _listen_for_messages(self):
        assert self._websocket is not None, "Not connected"

        try:
            async for message in self._websocket:
                try:
                    parsed = json.loads(message)
                    await self._handle_ws_event(parsed)
                except json.JSONDecodeError as e:
                    await self._emit_event(
                        RealtimeModelExceptionEvent(
                            exception=e, context="Failed to parse WebSocket message as JSON"
                        )
                    )
                except Exception as e:
                    await self._emit_event(
                        RealtimeModelExceptionEvent(
                            exception=e, context="Error handling WebSocket event"
                        )
                    )

        except websockets.exceptions.ConnectionClosedOK:
            # Normal connection closure - no exception event needed
            logger.debug("WebSocket connection closed normally")
        except websockets.exceptions.ConnectionClosed as e:
            await self._emit_event(
                RealtimeModelExceptionEvent(
                    exception=e, context="WebSocket connection closed unexpectedly"
                )
            )
        except Exception as e:
            await self._emit_event(
                RealtimeModelExceptionEvent(
                    exception=e, context="WebSocket error in message listener"
                )
            )

    async def send_event(self, event: RealtimeModelSendEvent) -> None:
        """Send an event to the model."""
        if isinstance(event, RealtimeModelSendRawMessage):
            converted = _ConversionHelper.try_convert_raw_message(event)
            if converted is not None:
                await self._send_raw_message(converted)
            else:
                logger.error(f"Failed to convert raw message: {event}")
        elif isinstance(event, RealtimeModelSendUserInput):
            await self._send_user_input(event)
        elif isinstance(event, RealtimeModelSendAudio):
            await self._send_audio(event)
        elif isinstance(event, RealtimeModelSendToolOutput):
            await self._send_tool_output(event)
        elif isinstance(event, RealtimeModelSendInterrupt):
            await self._send_interrupt(event)
        elif isinstance(event, RealtimeModelSendSessionUpdate):
            await self._send_session_update(event)
        else:
            assert_never(event)
            raise ValueError(f"Unknown event type: {type(event)}")

    async def _send_raw_message(self, event: OpenAIRealtimeClientEvent) -> None:
        """Send a raw message to the model."""
        assert self._websocket is not None, "Not connected"
        payload = event.model_dump_json(exclude_unset=True)
        await self._websocket.send(payload)

    async def _send_user_input(self, event: RealtimeModelSendUserInput) -> None:
        converted = _ConversionHelper.convert_user_input_to_item_create(event)
        await self._send_raw_message(converted)
        await self._send_raw_message(OpenAIResponseCreateEvent(type="response.create"))

    async def _send_audio(self, event: RealtimeModelSendAudio) -> None:
        converted = _ConversionHelper.convert_audio_to_input_audio_buffer_append(event)
        await self._send_raw_message(converted)
        if event.commit:
            await self._send_raw_message(
                OpenAIInputAudioBufferCommitEvent(type="input_audio_buffer.commit")
            )

    async def _send_tool_output(self, event: RealtimeModelSendToolOutput) -> None:
        converted = _ConversionHelper.convert_tool_output(event)
        await self._send_raw_message(converted)

        tool_item = RealtimeToolCallItem(
            item_id=event.tool_call.id or "",
            previous_item_id=event.tool_call.previous_item_id,
            call_id=event.tool_call.call_id,
            type="function_call",
            status="completed",
            arguments=event.tool_call.arguments,
            name=event.tool_call.name,
            output=event.output,
        )
        await self._emit_event(RealtimeModelItemUpdatedEvent(item=tool_item))

        if event.start_response:
            await self._send_raw_message(OpenAIResponseCreateEvent(type="response.create"))

    def _get_playback_state(self) -> RealtimePlaybackState:
        if self._playback_tracker:
            return self._playback_tracker.get_state()

        if last_audio_item_id := self._audio_state_tracker.get_last_audio_item():
            item_id, item_content_index = last_audio_item_id
            audio_state = self._audio_state_tracker.get_state(item_id, item_content_index)
            if audio_state:
                elapsed_ms = (
                    datetime.now() - audio_state.initial_received_time
                ).total_seconds() * 1000
                return {
                    "current_item_id": item_id,
                    "current_item_content_index": item_content_index,
                    "elapsed_ms": elapsed_ms,
                }

        return {
            "current_item_id": None,
            "current_item_content_index": None,
            "elapsed_ms": None,
        }

    async def _send_interrupt(self, event: RealtimeModelSendInterrupt) -> None:
        playback_state = self._get_playback_state()
        current_item_id = playback_state.get("current_item_id")
        current_item_content_index = playback_state.get("current_item_content_index")
        elapsed_ms = playback_state.get("elapsed_ms")

        if current_item_id is None or elapsed_ms is None:
            logger.debug(
                "Skipping interrupt. "
                f"Item id: {current_item_id}, "
                f"elapsed ms: {elapsed_ms}, "
                f"content index: {current_item_content_index}"
            )
        else:
            current_item_content_index = current_item_content_index or 0
            if elapsed_ms > 0:
                await self._emit_event(
                    RealtimeModelAudioInterruptedEvent(
                        item_id=current_item_id,
                        content_index=current_item_content_index,
                    )
                )
                converted = _ConversionHelper.convert_interrupt(
                    current_item_id,
                    current_item_content_index,
                    int(elapsed_ms),
                )
                await self._send_raw_message(converted)
            else:
                logger.debug(
                    "Didn't interrupt bc elapsed ms is < 0. "
                    f"Item id: {current_item_id}, "
                    f"elapsed ms: {elapsed_ms}, "
                    f"content index: {current_item_content_index}"
                )

        session = self._created_session
        automatic_response_cancellation_enabled = (
            session
            and session.audio is not None
            and session.audio.input is not None
            and session.audio.input.turn_detection is not None
            and session.audio.input.turn_detection.interrupt_response is True
        )
        should_cancel_response = event.force_response_cancel or (
            not automatic_response_cancellation_enabled
        )
        if should_cancel_response:
            await self._cancel_response()

        if current_item_id is not None and elapsed_ms is not None:
            self._audio_state_tracker.on_interrupted()
            if self._playback_tracker:
                self._playback_tracker.on_interrupted()

    async def _send_session_update(self, event: RealtimeModelSendSessionUpdate) -> None:
        """Send a session update to the model."""
        await self._update_session_config(event.session_settings)

    async def _handle_audio_delta(self, parsed: ResponseAudioDeltaEvent) -> None:
        """Handle audio delta events and update audio tracking state."""
        self._current_item_id = parsed.item_id

        audio_bytes = base64.b64decode(parsed.delta)

        self._audio_state_tracker.on_audio_delta(parsed.item_id, parsed.content_index, audio_bytes)

        await self._emit_event(
            RealtimeModelAudioEvent(
                data=audio_bytes,
                response_id=parsed.response_id,
                item_id=parsed.item_id,
                content_index=parsed.content_index,
            )
        )

    async def _handle_output_item(self, item: ConversationItem) -> None:
        """Handle response output item events (function calls and messages)."""
        if item.type == "function_call" and item.status == "completed":
            tool_call = RealtimeToolCallItem(
                item_id=item.id or "",
                previous_item_id=None,
                call_id=item.call_id,
                type="function_call",
                # We use the same item for tool call and output, so it will be completed by the
                # output being added
                status="in_progress",
                arguments=item.arguments or "",
                name=item.name or "",
                output=None,
            )
            await self._emit_event(RealtimeModelItemUpdatedEvent(item=tool_call))
            await self._emit_event(
                RealtimeModelToolCallEvent(
                    call_id=item.call_id or "",
                    name=item.name or "",
                    arguments=item.arguments or "",
                    id=item.id or "",
                )
            )
        elif item.type == "message":
            # Handle message items from output_item events (no previous_item_id)
            message_item: RealtimeMessageItem = TypeAdapter(RealtimeMessageItem).validate_python(
                {
                    "item_id": item.id or "",
                    "type": item.type,
                    "role": item.role,
                    "content": (
                        [content.model_dump() for content in item.content] if item.content else []
                    ),
                    "status": "in_progress",
                }
            )
            await self._emit_event(RealtimeModelItemUpdatedEvent(item=message_item))

    async def _handle_conversation_item(
        self, item: ConversationItem, previous_item_id: str | None
    ) -> None:
        """Handle conversation item creation/retrieval events."""
        message_item = _ConversionHelper.conversation_item_to_realtime_message_item(
            item, previous_item_id
        )
        await self._emit_event(RealtimeModelItemUpdatedEvent(item=message_item))

    async def close(self) -> None:
        """Close the session."""
        if self._websocket:
            await self._websocket.close()
            self._websocket = None
        if self._websocket_task:
            self._websocket_task.cancel()
            try:
                await self._websocket_task
            except asyncio.CancelledError:
                pass
            self._websocket_task = None

    async def _cancel_response(self) -> None:
        if self._ongoing_response:
            await self._send_raw_message(OpenAIResponseCancelEvent(type="response.cancel"))
            self._ongoing_response = False

    async def _handle_ws_event(self, event: dict[str, Any]):
        await self._emit_event(RealtimeModelRawServerEvent(data=event))
        # The public interface definedo on this Agents SDK side (e.g., RealtimeMessageItem)
        # must be the same even after the GA migration, so this part does the conversion
        if isinstance(event, dict) and event.get("type") in (
            "response.output_item.added",
            "response.output_item.done",
        ):
            item = event.get("item")
            if isinstance(item, dict) and item.get("type") == "message":
                raw_content = item.get("content") or []
                converted_content: list[dict[str, Any]] = []
                for part in raw_content:
                    if not isinstance(part, dict):
                        continue
                    if part.get("type") == "audio":
                        converted_content.append(
                            {
                                "type": "audio",
                                "audio": part.get("audio"),
                                "transcript": part.get("transcript"),
                            }
                        )
                    elif part.get("type") in ("text", "output_text"):
                        converted_content.append({"type": "text", "text": part.get("text")})
                status = item.get("status")
                if status not in ("in_progress", "completed", "incomplete"):
                    is_done = event.get("type") == "response.output_item.done"
                    status = "completed" if is_done else "in_progress"
                # Explicitly type the adapter for mypy
                type_adapter: TypeAdapter[RealtimeMessageItem] = TypeAdapter(RealtimeMessageItem)
                message_item: RealtimeMessageItem = type_adapter.validate_python(
                    {
                        "item_id": item.get("id", ""),
                        "type": "message",
                        "role": item.get("role", "assistant"),
                        "content": converted_content,
                        "status": status,
                    }
                )
                await self._emit_event(RealtimeModelItemUpdatedEvent(item=message_item))
                return

        try:
            if "previous_item_id" in event and event["previous_item_id"] is None:
                event["previous_item_id"] = ""  # TODO (rm) remove
            parsed: AllRealtimeServerEvents = self._server_event_type_adapter.validate_python(event)
        except pydantic.ValidationError as e:
            logger.error(f"Failed to validate server event: {event}", exc_info=True)
            await self._emit_event(RealtimeModelErrorEvent(error=e))
            return
        except Exception as e:
            event_type = event.get("type", "unknown") if isinstance(event, dict) else "unknown"
            logger.error(f"Failed to validate server event: {event}", exc_info=True)
            exception_event = RealtimeModelExceptionEvent(
                exception=e,
                context=f"Failed to validate server event: {event_type}",
            )
            await self._emit_event(exception_event)
            return

        if parsed.type == "response.output_audio.delta":
            await self._handle_audio_delta(parsed)
        elif parsed.type == "response.output_audio.done":
            audio_done_event = RealtimeModelAudioDoneEvent(
                item_id=parsed.item_id,
                content_index=parsed.content_index,
            )
            await self._emit_event(audio_done_event)
        elif parsed.type == "input_audio_buffer.speech_started":
            # On VAD speech start, immediately stop local playback so the user can
            # barge‑in without overlapping assistant audio.
            last_audio = self._audio_state_tracker.get_last_audio_item()
            if last_audio is not None:
                item_id, content_index = last_audio
                playback_state = self._get_playback_state()
                playback_item_id = playback_state.get("current_item_id")
                playback_content_index = playback_state.get("current_item_content_index") or 0
                playback_elapsed_ms = playback_state.get("elapsed_ms")
                await self._emit_event(
                    RealtimeModelAudioInterruptedEvent(item_id=item_id, content_index=content_index)
                )

                elapsed_override = getattr(parsed, "audio_end_ms", None)
                if elapsed_override is None or elapsed_override <= 0:
                    effective_elapsed_ms = playback_elapsed_ms
                else:
                    effective_elapsed_ms = float(elapsed_override)

                if playback_item_id and effective_elapsed_ms is not None:
                    truncated_ms = max(int(round(effective_elapsed_ms)), 0)
                    await self._send_raw_message(
                        _ConversionHelper.convert_interrupt(
                            playback_item_id,
                            playback_content_index,
                            truncated_ms,
                        )
                    )

                # Reset trackers so subsequent playback state queries don't
                # reference audio that has been interrupted client‑side.
                self._audio_state_tracker.on_interrupted()
                if self._playback_tracker:
                    self._playback_tracker.on_interrupted()

                # If server isn't configured to auto‑interrupt/cancel, cancel the
                # response to prevent further audio.
                session = self._created_session
                automatic_response_cancellation_enabled = (
                    session
                    and session.audio is not None
                    and session.audio.input is not None
                    and session.audio.input.turn_detection is not None
                    and session.audio.input.turn_detection.interrupt_response is True
                )
                if not automatic_response_cancellation_enabled:
                    await self._cancel_response()
        elif parsed.type == "response.created":
            self._ongoing_response = True
            await self._emit_event(RealtimeModelTurnStartedEvent())
        elif parsed.type == "response.done":
            self._ongoing_response = False
            await self._emit_event(RealtimeModelTurnEndedEvent())
        elif parsed.type == "session.created":
            await self._send_tracing_config(self._tracing_config)
            self._update_created_session(parsed.session)
        elif parsed.type == "session.updated":
            self._update_created_session(parsed.session)
        elif parsed.type == "error":
            await self._emit_event(RealtimeModelErrorEvent(error=parsed.error))
        elif parsed.type == "conversation.item.deleted":
            await self._emit_event(RealtimeModelItemDeletedEvent(item_id=parsed.item_id))
        elif (
            parsed.type == "conversation.item.added"
            or parsed.type == "conversation.item.created"
            or parsed.type == "conversation.item.retrieved"
        ):
            previous_item_id = (
                parsed.previous_item_id if parsed.type == "conversation.item.created" else None
            )
            if parsed.item.type == "message":
                await self._handle_conversation_item(parsed.item, previous_item_id)
        elif (
            parsed.type == "conversation.item.input_audio_transcription.completed"
            or parsed.type == "conversation.item.truncated"
        ):
            if self._current_item_id:
                await self._send_raw_message(
                    OpenAIConversationItemRetrieveEvent(
                        type="conversation.item.retrieve",
                        item_id=self._current_item_id,
                    )
                )
            if parsed.type == "conversation.item.input_audio_transcription.completed":
                await self._emit_event(
                    RealtimeModelInputAudioTranscriptionCompletedEvent(
                        item_id=parsed.item_id, transcript=parsed.transcript
                    )
                )
        elif parsed.type == "response.output_audio_transcript.delta":
            await self._emit_event(
                RealtimeModelTranscriptDeltaEvent(
                    item_id=parsed.item_id, delta=parsed.delta, response_id=parsed.response_id
                )
            )
        elif (
            parsed.type == "conversation.item.input_audio_transcription.delta"
            or parsed.type == "response.output_text.delta"
            or parsed.type == "response.function_call_arguments.delta"
        ):
            # No support for partials yet
            pass
        elif (
            parsed.type == "response.output_item.added"
            or parsed.type == "response.output_item.done"
        ):
            await self._handle_output_item(parsed.item)
        elif parsed.type == "input_audio_buffer.timeout_triggered":
            await self._emit_event(
                RealtimeModelInputAudioTimeoutTriggeredEvent(
                    item_id=parsed.item_id,
                    audio_start_ms=parsed.audio_start_ms,
                    audio_end_ms=parsed.audio_end_ms,
                )
            )

    def _update_created_session(
        self,
        session: OpenAISessionCreateRequest
        | OpenAIRealtimeTranscriptionSessionCreateRequest
        | Mapping[str, object]
        | pydantic.BaseModel,
    ) -> None:
        # Only store/playback-format information for realtime sessions (not transcription-only)
        normalized_session = self._normalize_session_payload(session)
        if not normalized_session:
            return

        self._created_session = normalized_session
        normalized_format = self._extract_audio_format(normalized_session)
        if normalized_format is None:
            return

        self._audio_state_tracker.set_audio_format(normalized_format)
        if self._playback_tracker:
            self._playback_tracker.set_audio_format(normalized_format)

    @staticmethod
    def _normalize_session_payload(
        session: OpenAISessionCreateRequest
        | OpenAIRealtimeTranscriptionSessionCreateRequest
        | Mapping[str, object]
        | pydantic.BaseModel,
    ) -> OpenAISessionCreateRequest | None:
        if isinstance(session, OpenAISessionCreateRequest):
            return session

        if isinstance(session, OpenAIRealtimeTranscriptionSessionCreateRequest):
            return None

        session_payload: Mapping[str, object]
        if isinstance(session, pydantic.BaseModel):
            session_payload = cast(Mapping[str, object], session.model_dump())
        elif isinstance(session, Mapping):
            session_payload = session
        else:
            return None

        if OpenAIRealtimeWebSocketModel._is_transcription_session(session_payload):
            return None

        try:
            return OpenAISessionCreateRequest.model_validate(session_payload)
        except pydantic.ValidationError:
            return None

    @staticmethod
    def _is_transcription_session(payload: Mapping[str, object]) -> bool:
        try:
            OpenAIRealtimeTranscriptionSessionCreateRequest.model_validate(payload)
        except pydantic.ValidationError:
            return False
        else:
            return True

    @staticmethod
    def _extract_audio_format(session: OpenAISessionCreateRequest) -> str | None:
        audio = session.audio
        if not audio or not audio.output or not audio.output.format:
            return None

        return OpenAIRealtimeWebSocketModel._normalize_audio_format(audio.output.format)

    @staticmethod
    def _normalize_audio_format(fmt: object) -> str:
        if isinstance(fmt, AudioPCM):
            return "pcm16"
        if isinstance(fmt, AudioPCMU):
            return "g711_ulaw"
        if isinstance(fmt, AudioPCMA):
            return "g711_alaw"

        fmt_type = OpenAIRealtimeWebSocketModel._read_format_type(fmt)
        if isinstance(fmt_type, str) and fmt_type:
            return fmt_type

        return str(fmt)

    @staticmethod
    def _read_format_type(fmt: object) -> str | None:
        if isinstance(fmt, str):
            return fmt

        if isinstance(fmt, Mapping):
            type_value = fmt.get("type")
            return type_value if isinstance(type_value, str) else None

        if isinstance(fmt, pydantic.BaseModel):
            type_value = fmt.model_dump().get("type")
            return type_value if isinstance(type_value, str) else None

        try:
            type_value = fmt.type  # type: ignore[attr-defined]
        except AttributeError:
            return None

        return type_value if isinstance(type_value, str) else None

    @staticmethod
    def _normalize_turn_detection_config(config: object) -> object:
        """Normalize camelCase turn detection keys to snake_case for API compatibility."""
        if not isinstance(config, Mapping):
            return config

        normalized = dict(config)
        key_map = {
            "createResponse": "create_response",
            "interruptResponse": "interrupt_response",
            "prefixPaddingMs": "prefix_padding_ms",
            "silenceDurationMs": "silence_duration_ms",
            "idleTimeoutMs": "idle_timeout_ms",
        }
        for camel_key, snake_key in key_map.items():
            if camel_key in normalized and snake_key not in normalized:
                normalized[snake_key] = normalized[camel_key]
            normalized.pop(camel_key, None)

        return normalized

    async def _update_session_config(self, model_settings: RealtimeSessionModelSettings) -> None:
        session_config = self._get_session_config(model_settings)
        await self._send_raw_message(
            OpenAISessionUpdateEvent(session=session_config, type="session.update")
        )

    def _get_session_config(
        self, model_settings: RealtimeSessionModelSettings
    ) -> OpenAISessionCreateRequest:
        """Get the session config."""
        audio_input_args: dict[str, Any] = {}
        audio_output_args: dict[str, Any] = {}

        audio_config = model_settings.get("audio")
        audio_config_mapping = audio_config if isinstance(audio_config, Mapping) else None
        input_audio_config: Mapping[str, Any] = (
            cast(Mapping[str, Any], audio_config_mapping.get("input", {}))
            if audio_config_mapping
            else {}
        )
        output_audio_config: Mapping[str, Any] = (
            cast(Mapping[str, Any], audio_config_mapping.get("output", {}))
            if audio_config_mapping
            else {}
        )

        input_format_source: FormatInput = (
            input_audio_config.get("format") if input_audio_config else None
        )
        if input_format_source is None:
            if self._call_id:
                input_format_source = model_settings.get("input_audio_format")
            else:
                input_format_source = model_settings.get(
                    "input_audio_format", DEFAULT_MODEL_SETTINGS.get("input_audio_format")
                )
        audio_input_args["format"] = to_realtime_audio_format(input_format_source)

        if "noise_reduction" in input_audio_config:
            audio_input_args["noise_reduction"] = input_audio_config.get("noise_reduction")
        elif "input_audio_noise_reduction" in model_settings:
            audio_input_args["noise_reduction"] = model_settings.get("input_audio_noise_reduction")

        if "transcription" in input_audio_config:
            audio_input_args["transcription"] = input_audio_config.get("transcription")
        elif "input_audio_transcription" in model_settings:
            audio_input_args["transcription"] = model_settings.get("input_audio_transcription")
        else:
            audio_input_args["transcription"] = DEFAULT_MODEL_SETTINGS.get(
                "input_audio_transcription"
            )

        if "turn_detection" in input_audio_config:
            audio_input_args["turn_detection"] = self._normalize_turn_detection_config(
                input_audio_config.get("turn_detection")
            )
        elif "turn_detection" in model_settings:
            audio_input_args["turn_detection"] = self._normalize_turn_detection_config(
                model_settings.get("turn_detection")
            )
        else:
            audio_input_args["turn_detection"] = DEFAULT_MODEL_SETTINGS.get("turn_detection")

        requested_voice = output_audio_config.get("voice") if output_audio_config else None
        audio_output_args["voice"] = requested_voice or model_settings.get(
            "voice", DEFAULT_MODEL_SETTINGS.get("voice")
        )

        output_format_source: FormatInput = (
            output_audio_config.get("format") if output_audio_config else None
        )
        if output_format_source is None:
            if self._call_id:
                output_format_source = model_settings.get("output_audio_format")
            else:
                output_format_source = model_settings.get(
                    "output_audio_format", DEFAULT_MODEL_SETTINGS.get("output_audio_format")
                )
        audio_output_args["format"] = to_realtime_audio_format(output_format_source)

        if "speed" in output_audio_config:
            audio_output_args["speed"] = output_audio_config.get("speed")
        elif "speed" in model_settings:
            audio_output_args["speed"] = model_settings.get("speed")

        output_modalities = (
            model_settings.get("output_modalities")
            or model_settings.get("modalities")
            or DEFAULT_MODEL_SETTINGS.get("modalities")
        )

        # Construct full session object. `type` will be excluded at serialization time for updates.
        session_create_request = OpenAISessionCreateRequest(
            type="realtime",
            model=(model_settings.get("model_name") or self.model) or "gpt-realtime",
            output_modalities=output_modalities,
            audio=OpenAIRealtimeAudioConfig(
                input=OpenAIRealtimeAudioInput(**audio_input_args),
                output=OpenAIRealtimeAudioOutput(**audio_output_args),
            ),
            tools=cast(
                Any,
                self._tools_to_session_tools(
                    tools=model_settings.get("tools", []),
                    handoffs=model_settings.get("handoffs", []),
                ),
            ),
        )

        if "instructions" in model_settings:
            session_create_request.instructions = model_settings.get("instructions")

        if "prompt" in model_settings:
            _passed_prompt: Prompt = model_settings["prompt"]
            variables: dict[str, Any] | None = _passed_prompt.get("variables")
            session_create_request.prompt = ResponsePrompt(
                id=_passed_prompt["id"],
                variables=variables,
                version=_passed_prompt.get("version"),
            )

        if "max_output_tokens" in model_settings:
            session_create_request.max_output_tokens = cast(
                Any, model_settings.get("max_output_tokens")
            )

        if "tool_choice" in model_settings:
            session_create_request.tool_choice = cast(Any, model_settings.get("tool_choice"))

        return session_create_request

    def _tools_to_session_tools(
        self, tools: list[Tool], handoffs: list[Handoff]
    ) -> list[OpenAISessionFunction]:
        converted_tools: list[OpenAISessionFunction] = []
        for tool in tools:
            if not isinstance(tool, FunctionTool):
                raise UserError(f"Tool {tool.name} is unsupported. Must be a function tool.")
            converted_tools.append(
                OpenAISessionFunction(
                    name=tool.name,
                    description=tool.description,
                    parameters=tool.params_json_schema,
                    type="function",
                )
            )

        for handoff in handoffs:
            converted_tools.append(
                OpenAISessionFunction(
                    name=handoff.tool_name,
                    description=handoff.tool_description,
                    parameters=handoff.input_json_schema,
                    type="function",
                )
            )

        return converted_tools

connect async

connect(options: RealtimeModelConfig) -> None

Establish a connection to the model and keep it alive.

Source code in src/agents/realtime/openai_realtime.py
async def connect(self, options: RealtimeModelConfig) -> None:
    """Establish a connection to the model and keep it alive."""
    assert self._websocket is None, "Already connected"
    assert self._websocket_task is None, "Already connected"

    model_settings: RealtimeSessionModelSettings = options.get("initial_model_settings", {})

    self._playback_tracker = options.get("playback_tracker", None)

    call_id = options.get("call_id")
    model_name = model_settings.get("model_name")
    if call_id and model_name:
        error_message = (
            "Cannot specify both `call_id` and `model_name` "
            "when attaching to an existing realtime call."
        )
        raise UserError(error_message)

    if model_name:
        self.model = model_name

    self._call_id = call_id
    api_key = await get_api_key(options.get("api_key"))

    if "tracing" in model_settings:
        self._tracing_config = model_settings["tracing"]
    else:
        self._tracing_config = "auto"

    if call_id:
        url = options.get("url", f"wss://api.openai.com/v1/realtime?call_id={call_id}")
    else:
        url = options.get("url", f"wss://api.openai.com/v1/realtime?model={self.model}")

    headers: dict[str, str] = {}
    if options.get("headers") is not None:
        # For customizing request headers
        headers.update(options["headers"])
    else:
        # OpenAI's Realtime API
        if not api_key:
            raise UserError("API key is required but was not provided.")

        headers.update({"Authorization": f"Bearer {api_key}"})
    self._websocket = await websockets.connect(
        url,
        user_agent_header=_USER_AGENT,
        additional_headers=headers,
        max_size=None,  # Allow any size of message
    )
    self._websocket_task = asyncio.create_task(self._listen_for_messages())
    await self._update_session_config(model_settings)

add_listener

add_listener(listener: RealtimeModelListener) -> None

Add a listener to the model.

Source code in src/agents/realtime/openai_realtime.py
def add_listener(self, listener: RealtimeModelListener) -> None:
    """Add a listener to the model."""
    if listener not in self._listeners:
        self._listeners.append(listener)

remove_listener

remove_listener(listener: RealtimeModelListener) -> None

Remove a listener from the model.

Source code in src/agents/realtime/openai_realtime.py
def remove_listener(self, listener: RealtimeModelListener) -> None:
    """Remove a listener from the model."""
    if listener in self._listeners:
        self._listeners.remove(listener)

send_event async

send_event(event: RealtimeModelSendEvent) -> None

Send an event to the model.

Source code in src/agents/realtime/openai_realtime.py
async def send_event(self, event: RealtimeModelSendEvent) -> None:
    """Send an event to the model."""
    if isinstance(event, RealtimeModelSendRawMessage):
        converted = _ConversionHelper.try_convert_raw_message(event)
        if converted is not None:
            await self._send_raw_message(converted)
        else:
            logger.error(f"Failed to convert raw message: {event}")
    elif isinstance(event, RealtimeModelSendUserInput):
        await self._send_user_input(event)
    elif isinstance(event, RealtimeModelSendAudio):
        await self._send_audio(event)
    elif isinstance(event, RealtimeModelSendToolOutput):
        await self._send_tool_output(event)
    elif isinstance(event, RealtimeModelSendInterrupt):
        await self._send_interrupt(event)
    elif isinstance(event, RealtimeModelSendSessionUpdate):
        await self._send_session_update(event)
    else:
        assert_never(event)
        raise ValueError(f"Unknown event type: {type(event)}")

close async

close() -> None

Close the session.

Source code in src/agents/realtime/openai_realtime.py
async def close(self) -> None:
    """Close the session."""
    if self._websocket:
        await self._websocket.close()
        self._websocket = None
    if self._websocket_task:
        self._websocket_task.cancel()
        try:
            await self._websocket_task
        except asyncio.CancelledError:
            pass
        self._websocket_task = None

OpenAIRealtimeSIPModel

Bases: OpenAIRealtimeWebSocketModel

Realtime model that attaches to SIP-originated calls using a call ID.

Source code in src/agents/realtime/openai_realtime.py
class OpenAIRealtimeSIPModel(OpenAIRealtimeWebSocketModel):
    """Realtime model that attaches to SIP-originated calls using a call ID."""

    @staticmethod
    async def build_initial_session_payload(
        agent: RealtimeAgent[Any],
        *,
        context: TContext | None = None,
        model_config: RealtimeModelConfig | None = None,
        run_config: RealtimeRunConfig | None = None,
        overrides: RealtimeSessionModelSettings | None = None,
    ) -> OpenAISessionCreateRequest:
        """Build a session payload that mirrors what a RealtimeSession would send on connect.

        This helper can be used to accept SIP-originated calls by forwarding the returned payload to
        the Realtime Calls API without duplicating session setup logic.
        """
        run_config_settings = (run_config or {}).get("model_settings") or {}
        initial_model_settings = (model_config or {}).get("initial_model_settings") or {}
        base_settings: RealtimeSessionModelSettings = {
            **run_config_settings,
            **initial_model_settings,
        }

        context_wrapper = RunContextWrapper(context)
        merged_settings = await _build_model_settings_from_agent(
            agent=agent,
            context_wrapper=context_wrapper,
            base_settings=base_settings,
            starting_settings=initial_model_settings,
            run_config=run_config,
        )

        if overrides:
            merged_settings.update(overrides)

        model = OpenAIRealtimeWebSocketModel()
        return model._get_session_config(merged_settings)

    async def connect(self, options: RealtimeModelConfig) -> None:
        call_id = options.get("call_id")
        if not call_id:
            raise UserError("OpenAIRealtimeSIPModel requires `call_id` in the model configuration.")

        sip_options = options.copy()
        await super().connect(sip_options)

build_initial_session_payload async staticmethod

build_initial_session_payload(
    agent: RealtimeAgent[Any],
    *,
    context: TContext | None = None,
    model_config: RealtimeModelConfig | None = None,
    run_config: RealtimeRunConfig | None = None,
    overrides: RealtimeSessionModelSettings | None = None,
) -> RealtimeSessionCreateRequest

Build a session payload that mirrors what a RealtimeSession would send on connect.

This helper can be used to accept SIP-originated calls by forwarding the returned payload to the Realtime Calls API without duplicating session setup logic.

Source code in src/agents/realtime/openai_realtime.py
@staticmethod
async def build_initial_session_payload(
    agent: RealtimeAgent[Any],
    *,
    context: TContext | None = None,
    model_config: RealtimeModelConfig | None = None,
    run_config: RealtimeRunConfig | None = None,
    overrides: RealtimeSessionModelSettings | None = None,
) -> OpenAISessionCreateRequest:
    """Build a session payload that mirrors what a RealtimeSession would send on connect.

    This helper can be used to accept SIP-originated calls by forwarding the returned payload to
    the Realtime Calls API without duplicating session setup logic.
    """
    run_config_settings = (run_config or {}).get("model_settings") or {}
    initial_model_settings = (model_config or {}).get("initial_model_settings") or {}
    base_settings: RealtimeSessionModelSettings = {
        **run_config_settings,
        **initial_model_settings,
    }

    context_wrapper = RunContextWrapper(context)
    merged_settings = await _build_model_settings_from_agent(
        agent=agent,
        context_wrapper=context_wrapper,
        base_settings=base_settings,
        starting_settings=initial_model_settings,
        run_config=run_config,
    )

    if overrides:
        merged_settings.update(overrides)

    model = OpenAIRealtimeWebSocketModel()
    return model._get_session_config(merged_settings)

add_listener

add_listener(listener: RealtimeModelListener) -> None

Add a listener to the model.

Source code in src/agents/realtime/openai_realtime.py
def add_listener(self, listener: RealtimeModelListener) -> None:
    """Add a listener to the model."""
    if listener not in self._listeners:
        self._listeners.append(listener)

remove_listener

remove_listener(listener: RealtimeModelListener) -> None

Remove a listener from the model.

Source code in src/agents/realtime/openai_realtime.py
def remove_listener(self, listener: RealtimeModelListener) -> None:
    """Remove a listener from the model."""
    if listener in self._listeners:
        self._listeners.remove(listener)

send_event async

send_event(event: RealtimeModelSendEvent) -> None

Send an event to the model.

Source code in src/agents/realtime/openai_realtime.py
async def send_event(self, event: RealtimeModelSendEvent) -> None:
    """Send an event to the model."""
    if isinstance(event, RealtimeModelSendRawMessage):
        converted = _ConversionHelper.try_convert_raw_message(event)
        if converted is not None:
            await self._send_raw_message(converted)
        else:
            logger.error(f"Failed to convert raw message: {event}")
    elif isinstance(event, RealtimeModelSendUserInput):
        await self._send_user_input(event)
    elif isinstance(event, RealtimeModelSendAudio):
        await self._send_audio(event)
    elif isinstance(event, RealtimeModelSendToolOutput):
        await self._send_tool_output(event)
    elif isinstance(event, RealtimeModelSendInterrupt):
        await self._send_interrupt(event)
    elif isinstance(event, RealtimeModelSendSessionUpdate):
        await self._send_session_update(event)
    else:
        assert_never(event)
        raise ValueError(f"Unknown event type: {type(event)}")

close async

close() -> None

Close the session.

Source code in src/agents/realtime/openai_realtime.py
async def close(self) -> None:
    """Close the session."""
    if self._websocket:
        await self._websocket.close()
        self._websocket = None
    if self._websocket_task:
        self._websocket_task.cancel()
        try:
            await self._websocket_task
        except asyncio.CancelledError:
            pass
        self._websocket_task = None