Lets end users add, authenticate, and manage MCP servers from the browser in assistant-ui apps with @assistant-ui/react-mcp. Use when building user-managed MCP server UIs: mounting McpManagerResource via useAui({ mcp }), declaring presets with defineConnector, dropping in McpConfigDialog, or composing McpManagerPrimitive (Root, Connectors, CustomServers, AddCustomTrigger), McpServerPrimitive (Root, Name, Icon, Status, ConnectButton, DisconnectButton, OAuthLink, RemoveButton, Error), and McpAddFo

Adds tracing, telemetry, and observability to an assistant-ui backend. Use when wiring an AI SDK route handler (streamText/generateText, toUIMessageStreamResponse) to a tracing backend: Langfuse via OpenTelemetry (LangfuseSpanProcessor and NodeSDK in instrumentation.ts, experimental_telemetry isEnabled, propagateAttributes with traceName/userId/sessionId, langfuseSpanProcessor.forceFlush on serverless), LangSmith via wrapAISDK(ai) from langsmith/experimental/vercel (createLangSmithProviderOption

Sets up assistant-ui Cloud persistence and authorization with the assistant-cloud package and AssistantCloud client. Use when adding cross-session thread/message persistence, multi-device chat history, file uploads, or auth to an assistant-ui app: passing the cloud option to useChatRuntime (with AssistantChatTransport from @assistant-ui/react-ai-sdk), configuring AssistantCloud with authToken (JWT), apiKey plus userId/workspaceId (server-side), or anonymous mode, and wiring auth providers like N

Upgrades an existing assistant-ui project to current releases and executes the resulting migrations. Use when the user wants to update, upgrade, bump, or migrate @assistant-ui/react, @assistant-ui/react-ai-sdk, ai, or @ai-sdk/react, hits peer-dependency conflicts or post-upgrade type errors, or must apply renamed APIs after a version jump. Detects installed versus latest versions via npm ls / npm view, then routes through breaking-change references for each jump (AI SDK v4/v5 to v6; assistant-ui

Installs and configures assistant-ui in a project via the CLI, and picks the right runtime for a backend. Use for first-time install, scaffold, or config: `npx assistant-ui@latest create my-app` (templates default, minimal, cloud, cloud-clerk, langgraph, mcp), `npx assistant-ui@latest init [--yes] [--overwrite]` in an existing Next.js app, or `npx assistant-ui@latest add` registry components (markdown-text, thread-list). Also use to choose a runtime hook for a backend: useChatRuntime (AI SDK), u

Implements multi-thread (conversation history) management in assistant-ui apps: rendering the prebuilt `ThreadList` next to `Thread`, or building a custom sidebar with `ThreadListPrimitive` and `ThreadListItemPrimitive` (Root, New, Items, Trigger, Title, Archive, Unarchive, Delete). Covers thread CRUD through the `useAui()`/`useAuiState()` API: `switchToThread`, `switchToNewThread`, and per item `rename`, `archive`, `unarchive`, `delete`, `generateTitle`, `initialize`, plus reading `s.threads.th

Guide to the assistant-ui runtime system, single-thread state, and the imperative runtime API in @assistant-ui/react. Use when creating a runtime (useLocalRuntime with a ChatModelAdapter, useExternalStoreRuntime for Redux/Zustand, useRemoteThreadListRuntime), wiring AssistantRuntimeProvider, or reading/mutating thread, message, and composer state and events. Covers the unified hooks useAui, useAuiState, useAuiEvent (composer.send, thread.runStart, thread.runEnd), legacy hooks (useAssistantRuntim

Registers LLM tools and renders custom tool-call UI in assistant-ui (@assistant-ui/react). Use when adding frontend-only tools with makeAssistantTool / useAssistantTool (browser actions like clipboard, navigation, localStorage, async-generator streaming, AbortSignal), rendering backend AI SDK tool() calls with makeAssistantToolUI / useAssistantToolUI (status.type running/complete/incomplete/requires-action, args, result, artifact via ToolCallMessagePartProps), building generative UI from tool re

Builds and customizes assistant-ui chat UI from composable, unstyled @assistant-ui/react primitives that follow Radix-style part composition. Use when assembling or styling a custom Thread, Composer, message rendering, action bar, or branch picker from building blocks: ThreadPrimitive (.Root, .Viewport, .Messages, .Empty, .ScrollToBottom), ComposerPrimitive (.Input, .Send, .Cancel, .Attachments), MessagePrimitive (.Parts/.Content, .Error), ActionBarPrimitive (.Copy, .Edit, .Reload, .Speak, feedb