ai

Use when adding a public teaching example or a docs tutorial. Don't use for an internal Nx playground (that is new-react-playground), for a package API change with no walkthrough, or for a docs-only copy edit.

Use when adding a public teaching example or a docs tutorial. Don't use for an internal Nx playground (that is new-react-playground), for a package API change with no walkthrough, or for a docs-only copy edit.

Use when adding a public teaching example or a docs tutorial. Don't use for an internal Nx playground (that is new-react-playground), for a package API change with no walkthrough, or for a docs-only copy edit.

LLM-generated TypeScript execution in sandboxed environments: createCodeModeTool() with isolate drivers (createNodeIsolateDriver, createQuickJSIsolateDriver, createQuickJSBunIsolateDriver, createCloudflareIsolateDriver), codeModeWithSnippets() for persistent snippet libraries, trust strategies, snippet storage (FileSystem, LocalStorage, InMemory, Mongo), client-side execution progress via code_mode:* custom events in useChat.

Entry point for TanStack AI skills. Routes to chat-experience, tool-calling, media-generation, structured-outputs, adapter-configuration, ag-ui-protocol, middleware, locks, custom-backend-integration, and debug-logging, plus the skills shipped by companion packages (@tanstack/ai-persistence, @tanstack/ai-code-mode). Use chat() not streamText(), openaiText() not createOpenAI(), toServerSentEventsResponse() not manual SSE, middleware hooks not onEnd callbacks.

Provider adapter selection and configuration: openaiText, anthropicText, geminiText, ollamaText, grokText, groqText, openRouterText, bedrockText, byteplusText, openaiCompatible. Per-model type safety with modelOptions, reasoning/thinking configuration, runtime adapter switching, extendAdapter() for custom models, createModel(). Generic OpenAI-compatible providers (DeepSeek, Together, Fireworks, etc.) via openaiCompatible({ baseURL, apiKey, models }) from @tanstack/ai-openai/compatible. API key env vars: OPENAI_API_KEY, ANTHROPIC_API_KEY, GOOGLE_API_KEY/GEMINI_API_KEY, XAI_API_KEY, GROQ_API_KEY, OPENROUTER_API_KEY, OLLAMA_HOST, BEDROCK_API_KEY (or AWS_BEARER_TOKEN_BEDROCK). BytePlus needs TWO keys: ARK_API_KEY (ModelArk — chat/video/image) and BYTEPLUS_VOICE_API_KEY (Seed Speech — TTS/transcription); neither is a fallback for the other.

Server-side AG-UI streaming protocol implementation: StreamChunk event types (RUN_STARTED, TEXT_MESSAGE_START/CONTENT/END, TOOL_CALL_START/ARGS/END, RUN_FINISHED, RUN_ERROR, STEP_STARTED/STEP_FINISHED, STATE_SNAPSHOT/DELTA, CUSTOM), toServerSentEventsStream() for SSE format, toHttpStream() for NDJSON format. For backends serving AG-UI events without client packages.

End-to-end chat implementation: server endpoint with chat() and toServerSentEventsResponse(), client-side useChat hook with fetchServerSentEvents(), message rendering with UIMessage parts, multimodal content, thinking/reasoning display. Covers streaming states, connection adapters, and message format conversions. NOT Vercel AI SDK — uses chat() not streamText().

Browser chat persistence on useChat / ChatClient: localStoragePersistence, sessionStoragePersistence, indexedDBPersistence. Client-authoritative (adapter, full transcript) vs server-authoritative (persistence: true, no client cache). Reload restore, pending interrupts, mid-stream rejoin with delivery durability. Use for SPA reload durability — NOT server history alone. Also covers generation hooks (useGenerateImage etc.), which take only the server-driven mode: persistence: true hydrates the last generation for the (REQUIRED) threadId from the server on mount and repaints status/result/error, nothing is cached in the browser. No extra package: the adapters ship in the framework packages.

Connect useChat to a non-TanStack-AI backend through custom connection adapters. ConnectConnectionAdapter (single async iterable) vs SubscribeConnectionAdapter (separate subscribe/send). Customize fetchServerSentEvents() and fetchHttpStream() with auth headers, custom URLs, and request options. Import from framework package, not @tanstack/ai-client.

Pluggable, category-toggleable debug logging for TanStack AI activities. Toggle with `debug: true | false | DebugConfig` on chat(), summarize(), generateImage(), generateSpeech(), generateTranscription(), generateVideo(). Categories: request, provider, output, middleware, tools, agentLoop, config, errors. Pipe into pino/winston/etc via `debug: { logger }`. Errors log by default even when `debug` is omitted; silence with `debug: false`.

LockStore, InMemoryLockStore, LocksCapability and withLocks for multi-instance coordination in TanStack AI. Ships in @tanstack/ai — NOT in @tanstack/ai-persistence. Separate from AIPersistence state stores — not a stores key, not composable. InMemoryLockStore vs a distributed (e.g. Cloudflare Durable Object) lock, lease recovery, AbortSignal in critical sections. Use when sandbox or other middleware needs cross-worker mutual exclusion — NOT for storing messages/runs (use withPersistence).

Image, audio, video, speech (TTS), and transcription generation using activity-specific adapters: generateImage() with openaiImage/geminiImage/byteplusImage, generateAudio() with geminiAudio/falAudio, generateVideo() with async polling (openaiVideo/geminiVideo/grokVideo/falVideo/byteplusVideo/openRouterVideo, per-model typed durations), generateSpeech() with openaiSpeech/byteplusSpeech/elevenlabsSpeech, generateTranscription() with openaiTranscription/byteplusTranscription, generateVoice() with elevenlabsVoiceDesign (create a voice, then speak with it). React hooks: useGenerateImage, useGenerateAudio, useGenerateSpeech, useTranscription, useGenerateVideo. TanStack Start server function integration with toServerSentEventsResponse.

Chat lifecycle middleware hooks: onConfig, onStart, onChunk, onBeforeToolCall, onAfterToolCall, onUsage, onFinish, onAbort, onError. Use for analytics, event firing, tool caching (toolCacheMiddleware), logging, and tracing. Middleware array in chat() config, left-to-right execution order. NOT onEnd/onFinish callbacks on chat() — use middleware.

Type-safe JSON schema responses from LLMs using outputSchema on chat() and useChat(). Supports Zod, ArkType, and Valibot schemas. The adapter handles provider-specific strategies transparently — never configure structured output at the provider level. Pass stream:true alongside outputSchema for incremental JSON deltas + a completed typed object via the `structured-output.complete` event. Each successfully completed structured-output run adds a typed `StructuredOutputPart` to message history. partial/final derive from the most recent structured-output part after the latest user message. convertSchemaToJsonSchema() for manual schema conversion.

Isomorphic tool system: toolDefinition() with Zod schemas, .server() and .client() implementations, passing tools to both chat() on server and useChat/clientTools on client, tool approval flows with needsApproval and bound interrupts (resolveInterrupt), generic middleware interrupts with defineInterrupt(), lazy tool discovery with lazy:true, rendering ToolCallPart and ToolResultPart in UI.

Host-side Model Context Protocol (MCP) for TanStack AI: connect to external MCP servers, host your own tools with createMCPServer, discover and run tools inside any adapter's chat() loop, read resources and prompts, generate TypeScript types (typed tool names/pool keys) with the bundled CLI, and manage lifecycle with close()/await using.

Durability and state persistence for TanStack AI chats with @tanstack/ai-persistence. Routes to server chat persistence (withPersistence), client persistence (localStorage/IndexedDB), the store contracts, and adapter recipes. Distinguishes delivery durability (resumable streams) from conversation state. Use when conversations must survive reloads, multi-device, approvals, or server restarts — NOT for stream reconnect alone.

Use when a Cloudflare Worker needs TanStack AI chat persistence — writes a chat-persistence.ts into the app against its D1 binding (raw or via Drizzle), plus a Durable Object LockStore. Covers per-request bindings, wrangler config, D1 migrations, and lease-based locks.

Use when an app needs TanStack AI chat persistence on a database with no dedicated recipe — raw Postgres (pg/postgres.js), Kysely, node:sqlite, MongoDB, Supabase, Redis. Writes a chat-persistence.ts against the app's existing client, covering the four stores, the idempotency invariants, and the conformance gate. Route to the Drizzle, Prisma, or Cloudflare skills instead when one of those matches.