RealtimeTransportLayer

The transport layer is the layer that handles the connection to the model and the communication with the model.

Extends

• EventEmitter<RealtimeTransportEventTypes>

Properties

muted

readonly muted: boolean | null;

Whether the input audio track is currently muted null if the muting is not handled by the transport layer

---

status

status: "connecting" | "connected" | "disconnected" | "disconnecting";

Methods

addImage()

addImage(image, options?): void;

Sends an image to the model

Parameters

Parameter	Type	Description
image	string	The image to send
options?	{ triggerResponse?: boolean; }	Additional options
options.triggerResponse?	boolean	Whether to trigger a response from the model

Returns

void

---

close()

close(): void;

Closes the connection to the model

Returns

void

---

connect()

connect(options): Promise<void>;

Establishes the connection to the model and keeps the connection alive

Parameters

Parameter	Type	Description
options	RealtimeTransportLayerConnectOptions	The options for the connection

Returns

Promise<void>

---

emit()

emit<K>(type, ...args): boolean;

Type Parameters

Type Parameter
K extends keyof RealtimeTransportEventTypes

Parameters

Parameter	Type
type	K
…args	RealtimeTransportEventTypes[K]

Returns

boolean

Inherited from

EventEmitter.emit

---

getDefaultAudioFormat()?

optional getDefaultAudioFormat(): RealtimeAudioFormat;

The default format for both input and output audio. RealtimeSession calls this when constructed, before applying caller configuration. Transports that omit this hook retain the session’s PCM 24 kHz defaults. Explicit caller formats take precedence over this default; partial audio settings retain it for directions without an explicit format.

Returns

RealtimeAudioFormat

---

interrupt()

interrupt(): void;

Interrupts the current turn. Used for example when a guardrail is triggered

Returns

void

---

mute()

mute(muted): void;

Mutes the input audio track

Parameters

Parameter	Type	Description
muted	boolean	Whether to mute the input audio track

Returns

void

---

off()

off<K>(type, listener): EventEmitter<RealtimeTransportEventTypes>;

Type Parameters

Type Parameter
K extends keyof RealtimeTransportEventTypes

Parameters

Parameter	Type
type	K
listener	(…args) => void

Returns

EventEmitter<RealtimeTransportEventTypes>

Inherited from

EventEmitter.off

---

on()

on<K>(type, listener): EventEmitter<RealtimeTransportEventTypes>;

Type Parameters

Type Parameter
K extends keyof RealtimeTransportEventTypes

Parameters

Parameter	Type
type	K
listener	(…args) => void

Returns

EventEmitter<RealtimeTransportEventTypes>

Inherited from

EventEmitter.on

---

once()

once<K>(type, listener): EventEmitter<RealtimeTransportEventTypes>;

Type Parameters

Type Parameter
K extends keyof RealtimeTransportEventTypes

Parameters

Parameter	Type
type	K
listener	(…args) => void

Returns

EventEmitter<RealtimeTransportEventTypes>

Inherited from

EventEmitter.once

---

requestResponse()?

optional requestResponse(response?): void;

Requests a new response for the current conversation turn. Implementations may defer the underlying response.create until the server has fully finished the prior response.

Parameters

Parameter	Type	Description
response?	Record<string, any>	Optional one-off response override payload.

Returns

void

---

resetHistory()

resetHistory(oldHistory, newHistory): void;

Resets the conversation history / context to a specific state

Parameters

Parameter	Type	Description
oldHistory	RealtimeItem[]	The history that is currently stored on the session.
newHistory	RealtimeItem[]	The history you want the session to use going forward.

Returns

void

---

sendAudio()

sendAudio(audio, options): void;

Sends a raw audio buffer to the model

Parameters

Parameter	Type	Description
audio	ArrayBuffer	The audio buffer to send
options	{ commit?: boolean; }	Additional options
options.commit?	boolean	Whether to commit the audio buffer to the model. If the model does not do turn detection, this can be used to indicate the turn is completed.

Returns

void

---

sendEvent()

sendEvent(event): void;

Sends a raw event to the model

Parameters

Parameter	Type	Description
event	RealtimeClientMessage	The event to send

Returns

void

---

sendFunctionCallOutput()

sendFunctionCallOutput(
   toolCall,
   output,
   startResponse
): void;

Sends a function call output to the model

Parameters

Parameter	Type	Description
toolCall	TransportToolCallEvent	The tool call to send
output	string	The output of the tool call
startResponse	boolean	‐

Returns

void

---

sendMcpResponse()

sendMcpResponse(
   approvalRequest,
   approved,
   reason?
): void;

Sends a response for an MCP tool call

Parameters

Parameter	Type	Description
approvalRequest	{ approved?: boolean | null; arguments: Record<string, any>; itemId: string; name: string; serverLabel: string; type: "mcp_approval_request"; }	The approval request to respond to
approvalRequest.approved?	boolean | null	‐
approvalRequest.arguments	Record<string, any>	‐
approvalRequest.itemId?	string	‐
approvalRequest.name?	string	‐
approvalRequest.serverLabel?	string	‐
approvalRequest.type?	"mcp_approval_request"	‐
approved?	boolean	Whether the tool call was approved or rejected
reason?	string	Optional rejection text for the provider/model.

Returns

void

---

sendMessage()

sendMessage(
   message,
   otherEventData,
   options?
): void;

Sends a text message to the model

Parameters

Parameter	Type	Description
message	RealtimeUserInput	The message to send
otherEventData	Record<string, any>	Additional event data, will be merged into the event
options?	{ triggerResponse?: boolean; }	Additional options
options.triggerResponse?	boolean	Whether to trigger a response from the model

Returns

void

---

updateSessionConfig()

updateSessionConfig(config): void;

Sends an updated session configuration to the model. Used to update for example the model instructions during a handoff

Parameters

Parameter	Type	Description
config	Partial<RealtimeSessionConfig>	The new session config

Returns

void