📄 ai-sdk/docs/reference/ai-sdk-rsc/stream-ui

AI SDK RSC is currently experimental. We recommend using AI SDK UI for production. For guidance on migrating from RSC to UI, see our migration guide .

A helper function to create a streamable UI from LLM providers. This function is similar to AI SDK Core APIs and supports the same model interfaces.

To see streamUI in action, check out these examples .

Import

import { streamUI } from "@ai-sdk/rsc"

Parameters

model:

LanguageModel

The language model to use. Example: openai("gpt-4.1")

initial?:

ReactNode

The initial UI to render.

system:

string

The system prompt to use that specifies the behavior of the model.

prompt:

string

The input prompt to generate the text from.

messages:

Array<CoreSystemMessage | CoreUserMessage | CoreAssistantMessage | CoreToolMessage> | Array<UIMessage>

A list of messages that represent a conversation. Automatically converts UI messages from the useChat hook.

CoreSystemMessage

role:

'system'

The role for the system message.

content:

string

The content of the message.

CoreUserMessage

role:

'user'

The role for the user message.

content:

string | Array<TextPart | ImagePart | FilePart>

The content of the message.

TextPart

type:

'text'

The type of the message part.

text:

string

The text content of the message part.

ImagePart

type:

'image'

The type of the message part.

image:

string | Uint8Array | Buffer | ArrayBuffer | URL

The image content of the message part. String are either base64 encoded content, base64 data URLs, or http(s) URLs.

mediaType?:

string

The IANA media type of the image. Optional.

FilePart

type:

'file'

The type of the message part.

data:

string | Uint8Array | Buffer | ArrayBuffer | URL

The file content of the message part. String are either base64 encoded content, base64 data URLs, or http(s) URLs.

mediaType:

string

The IANA media type of the file.

CoreAssistantMessage

role:

'assistant'

The role for the assistant message.

content:

string | Array<TextPart | ToolCallPart>

The content of the message.

TextPart

type:

'text'

The type of the message part.

text:

string

The text content of the message part.

ToolCallPart

type:

'tool-call'

The type of the message part.

toolCallId:

string

The id of the tool call.

toolName:

string

The name of the tool, which typically would be the name of the function.

args:

object based on zod schema

Parameters generated by the model to be used by the tool.

CoreToolMessage

role:

'tool'

The role for the assistant message.

content:

Array<ToolResultPart>

The content of the message.

ToolResultPart

type:

'tool-result'

The type of the message part.

toolCallId:

string

The id of the tool call the result corresponds to.

toolName:

string

The name of the tool the result corresponds to.

result:

unknown

The result returned by the tool after execution.

isError?:

boolean

Whether the result is an error or an error message.

maxOutputTokens?:

number

Maximum number of tokens to generate.

temperature?:

number

Temperature setting. The value is passed through to the provider. The range depends on the provider and model. It is recommended to set either `temperature` or `topP`, but not both.

topP?:

number

Nucleus sampling. The value is passed through to the provider. The range depends on the provider and model. It is recommended to set either `temperature` or `topP`, but not both.

topK?:

number

Only sample from the top K options for each subsequent token. Used to remove "long tail" low probability responses. Recommended for advanced use cases only. You usually only need to use temperature.

presencePenalty?:

number

Presence penalty setting. It affects the likelihood of the model to repeat information that is already in the prompt. The value is passed through to the provider. The range depends on the provider and model.

frequencyPenalty?:

number

Frequency penalty setting. It affects the likelihood of the model to repeatedly use the same words or phrases. The value is passed through to the provider. The range depends on the provider and model.

stopSequences?:

string[]

Sequences that will stop the generation of the text. If the model generates any of these sequences, it will stop generating further text.

seed?:

number

The seed (integer) to use for random sampling. If set and supported by the model, calls will generate deterministic results.

maxRetries?:

number

Maximum number of retries. Set to 0 to disable retries. Default: 2.

abortSignal?:

AbortSignal

An optional abort signal that can be used to cancel the call.

headers?:

Record<string, string>

Additional HTTP headers to be sent with the request. Only applicable for HTTP-based providers.

tools:

ToolSet

Tools that are accessible to and can be called by the model.

Tool

description?:

string

Information about the purpose of the tool including details on how and when it can be used by the model.

parameters:

zod schema

The typed schema that describes the parameters of the tool that can also be used to validation and error handling.

generate?:

(async (parameters) => ReactNode) | AsyncGenerator<ReactNode, ReactNode, void>

A function or a generator function that is called with the arguments from the tool call and yields React nodes as the UI.

toolChoice?:

"auto" | "none" | "required" | { "type": "tool", "toolName": string }

The tool choice setting. It specifies how tools are selected for execution. The default is "auto". "none" disables tool execution. "required" requires tools to be executed. { "type": "tool", "toolName": string } specifies a specific tool to execute.

text?:

(Text) => ReactNode

Callback to handle the generated tokens from the model.

Text

content:

string

The full content of the completion.

delta:

string

The delta.

done:

boolean

Is it done?

providerOptions?:

Record<string,Record<string,JSONValue>> | undefined

Provider-specific options. The outer key is the provider name. The inner values are the metadata. Details depend on the provider.

onFinish?:

(result: OnFinishResult) => void

Callback that is called when the LLM response and all request tool executions (for tools that have a `generate` function) are finished.

OnFinishResult

usage:

TokenUsage

The token usage of the generated text.

TokenUsage

promptTokens:

number

The total number of tokens in the prompt.

completionTokens:

number

The total number of tokens in the completion.

totalTokens:

number

The total number of tokens generated.

value:

ReactNode

The final ui node that was generated.

warnings:

Warning[] | undefined

Warnings from the model provider (e.g. unsupported settings).

response:

Response

Optional response data.

Response

headers?:

Record<string, string>

Response headers.

Returns

value:

ReactNode

The user interface based on the stream output.

response?:

Response

Optional response data.

Response

headers?:

Record<string, string>

Response headers.

warnings:

Warning[] | undefined

Warnings from the model provider (e.g. unsupported settings).

stream:

AsyncIterable<StreamPart> & ReadableStream<StreamPart>

A stream with all events, including text deltas, tool calls, tool results, and errors. You can use it as either an AsyncIterable or a ReadableStream. When an error occurs, the stream will throw the error.

StreamPart