langgraph/libs/sdk-js/docs/react/interfaces/UseStreamOptions.md

@langchain/langgraph-sdk

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@langchain/langgraph-sdk / UseStreamOptions

Interface: UseStreamOptions<StateType, Bag>

Defined in: react/stream.tsx:413

Type Parameters

• StateType extends Record<string, unknown> = Record<string, unknown>

• Bag extends BagTemplate = BagTemplate

Properties

apiKey?

optional apiKey: string

Defined in: react/stream.tsx:435

The API key to use.

---

apiUrl?

optional apiUrl: string

Defined in: react/stream.tsx:430

The URL of the API to use.

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assistantId

assistantId: string

Defined in: react/stream.tsx:420

The ID of the assistant to use.

---

callerOptions?

optional callerOptions: AsyncCallerParams

Defined in: react/stream.tsx:440

Custom call options, such as custom fetch implementation.

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client?

optional client: Client<DefaultValues, DefaultValues, unknown>

Defined in: react/stream.tsx:425

Client used to send requests.

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defaultHeaders?

optional defaultHeaders: Record<string, HeaderValue>

Defined in: react/stream.tsx:445

Default headers to send with requests.

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messagesKey?

optional messagesKey: string

Defined in: react/stream.tsx:453

Specify the key within the state that contains messages. Defaults to "messages".

Default

"messages"

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onCreated()?

optional onCreated: (run) => void

Defined in: react/stream.tsx:471

Callback that is called when a new stream is created.

Parameters

run

RunCallbackMeta

Returns

void

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onCustomEvent()?

optional onCustomEvent: (data, options) => void

Defined in: react/stream.tsx:483

Callback that is called when a custom event is received.

Parameters

data

GetCustomEventType<Bag>

options

mutate

(update) => void

Returns

void

---

onDebugEvent()?

optional onDebugEvent: (data) => void

Defined in: react/stream.tsx:507

Internal

Callback that is called when a debug event is received. This API is experimental and subject to change.

Parameters

data

unknown

Returns

void

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onError()?

optional onError: (error, run) => void

Defined in: react/stream.tsx:458

Callback that is called when an error occurs.

Parameters

error

unknown

run

undefined | RunCallbackMeta

Returns

void

---

onFinish()?

optional onFinish: (state, run) => void

Defined in: react/stream.tsx:463

Callback that is called when the stream is finished.

Parameters

state

ThreadState<StateType>

run

undefined | RunCallbackMeta

Returns

void

---

onLangChainEvent()?

optional onLangChainEvent: (data) => void

Defined in: react/stream.tsx:501

Callback that is called when a LangChain event is received.

Parameters

data

data

unknown

event

string & object | "on_tool_start" | "on_tool_stream" | "on_tool_end" | "on_chat_model_start" | "on_chat_model_stream" | "on_chat_model_end" | "on_llm_start" | "on_llm_stream" | "on_llm_end" | "on_chain_start" | "on_chain_stream" | "on_chain_end" | "on_retriever_start" | "on_retriever_stream" | "on_retriever_end" | "on_prompt_start" | "on_prompt_stream" | "on_prompt_end"

metadata

Record<string, unknown>

name

string

parent_ids

string[]

run_id

string

tags

string[]

Returns

void

See

https://langchain-ai.github.io/langgraph/cloud/how-tos/stream_events/#stream-graph-in-events-mode for more details.

---

onMetadataEvent()?

optional onMetadataEvent: (data) => void

Defined in: react/stream.tsx:495

Callback that is called when a metadata event is received.

Parameters

data

run_id

string

thread_id

string

Returns

void

---

onThreadId()?

optional onThreadId: (threadId) => void

Defined in: react/stream.tsx:517

Callback that is called when the thread ID is updated (ie when a new thread is created).

Parameters

threadId

string

Returns

void

---

onUpdateEvent()?

optional onUpdateEvent: (data) => void

Defined in: react/stream.tsx:476

Callback that is called when an update event is received.

Parameters

data

Returns

void

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reconnectOnMount?

optional reconnectOnMount: boolean | () => RunMetadataStorage

Defined in: react/stream.tsx:520

Will reconnect the stream on mount

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threadId?

optional threadId: null | string

Defined in: react/stream.tsx:512

The ID of the thread to fetch history and current values from.