AI Tool

assistant-ui Review

assistant-ui provides open-source React primitives and a starter configuration for building AI chat UIs, supporting generative UI and frontend tool calls.

shipped Jul 23, 2026codefreemium

Domain rating46Monthly visits3.5K/mo

codeimage-generationagents

Why it matters

1Over 50,000 monthly downloads as of January 2026 for its core library.

2Offers a terminal UI version via `@assistant-ui/react-ink`.

3Integrates with Vercel AI SDK, LangGraph, LangChain, and LangSmith.

4Expanded to support React Native for mobile applications in March 2026.

Specs

API Docs

View Documentation →

GitHub

View Repository →

API Available

Yes, public API

overview

What is assistant-ui?

assistant-ui is an open-source TypeScript/React library that enables developers to quickly build production-grade AI chat interfaces, offering a ChatGPT-like user experience within their applications. It provides a set of composable React components and state management layers for creating highly customizable conversational AI experiences, handling functionalities such as streaming responses, auto-scrolling, markdown rendering, and accessibility out-of-the-box. The library emphasizes composable React components and integrates with various backends, including Vercel AI SDK and LangGraph. It is a React/TypeScript library focused on the frontend for AI agents, specifically chat UIs, and also offers a terminal UI version.

features

Key Features of assistant-ui

assistant-ui offers a comprehensive set of features designed to streamline the development of AI chat interfaces, providing both foundational primitives and advanced functionalities for production environments.

Open-source React primitives for building customizable AI chat UIs.
Starter configuration for rapid deployment of AI chat interfaces.
Support for generative UI, enabling dynamic interface updates from AI responses.
Frontend tool calls for integrating AI agent actions directly into the UI.
Composable React components for flexible and modular development.
Integration with Vercel AI SDK for enhanced AI backend connectivity.
Integration with LangGraph, LangChain, and LangSmith for agent orchestration.
Terminal UI version available via @assistant-ui/react-ink.
Instant ChatGPT-style UX with theming and sensible defaults.
Advanced state management for streaming, interruptions, retries, and multi-turn conversations.
High performance with optimized rendering and minimal bundle size.
Compatibility with any LLM provider, ensuring broad backend flexibility.

use cases

Who Should Use assistant-ui?

assistant-ui is primarily designed for developers and teams looking to integrate sophisticated AI chat capabilities into their applications with a focus on customization and production readiness.

Developers building in-app AI assistants for existing web applications.
Teams creating customer support chatbots requiring responsive and interactive interfaces.
Engineers developing personal AI assistants or customized AI companions.
Organizations building complex multi-agent applications that need robust frontend interaction.
Developers prototyping and deploying GPT wrappers or ChatGPT clones rapidly.

how to use

How to Use assistant-ui

To begin using assistant-ui, developers typically install the library via npm or yarn and then integrate its React components into their application. The process involves setting up the chat interface and connecting it to an AI backend.

1Install the @assistant-ui/react package using npm or yarn.
2Import and utilize the provided React components, such as AssistantUI and Thread, within a React application.
3Configure the chat interface to connect with an AI backend, such as Vercel AI SDK or LangGraph.
4Implement state management for handling streaming responses, user input, and conversation history.
5Customize the UI components using theming options or by replacing default components with custom implementations.
6Deploy the application to a web server or integrate it into an existing web application.

pricing

assistant-ui Pricing & Plans

assistant-ui operates on a freemium model, offering its core library as open-source while providing additional services and features through Assistant Cloud. The open-source components are freely available for use and modification. Assistant Cloud, which received a redesign in March 2026, offers a hosted backend service for managing AI assistants at scale, including thread persistence, analytics, and user management. A standalone package, @assistant-ui/cloud-ai-sdk, is available for adding thread persistence and management to Vercel AI SDK applications.

Open-source core library: Free (available on GitHub and npm).
Assistant Cloud: Offers a hosted backend service with a new dashboard for managing AI assistants, including thread persistence, analytics, and user management (specific pricing details for Assistant Cloud are not publicly detailed in the provided data).
@assistant-ui/cloud-ai-sdk: Standalone package for thread persistence and management in Vercel AI SDK applications (pricing not detailed).

Pros

+Provides open-source React primitives for maximum UI customization and control.
+Offers a quick time-to-value, enabling production deployment in as little as two hours for some users.
+Supports a wide array of AI model providers and backends, including Vercel AI SDK and LangGraph.
+Handles complex chat functionalities like streaming, auto-scrolling, and markdown rendering out-of-the-box.
+Expanded to support React Native for mobile and terminal UIs (via @assistant-ui/react-ink).
+Boasts over 50,000 monthly downloads as of January 2026, indicating strong developer adoption.

Cons

−Documentation can be 'rough' for specific edge cases, particularly concerning message schemas and tool output reliability.
−The framework is primarily 'React-only,' which may limit adoption for projects not using React.
−Integration with certain backends like Smolagents has shown issues with tool output reliability.

Policies

Pricing Page

View Pricing→

Similar Tools

assistant-ui vs Competitors

assistant-ui distinguishes itself in the AI chat UI landscape through its open-source nature, composable React primitives, and broad backend compatibility, offering developers extensive control over the user interface.

Vercel AI SDK (with AI Elements)On Stork

Provides a TypeScript toolkit with `streamUI()` for server-streamed components and pre-built UI primitives (AI Elements) specifically for agent interfaces, with first-class support for React Server Components.

Similar to assistant-ui in offering React components for AI chat UIs and supporting generative UI. Vercel AI SDK is developed by Vercel, a major player in the Next.js ecosystem, and offers a more integrated experience within the Vercel platform, while assistant-ui focuses on being a backend-agnostic React library.

CopilotKit↗

An enterprise-ready frontend stack for AI agents that enables generative UI apps across web, Slack, and Teams, and is the company behind the AG-UI protocol.

Like assistant-ui, it provides an open-source frontend stack for agentic UIs with pre-built chat components and generative UI rendering. CopilotKit emphasizes enterprise readiness and broader platform integration (Slack, Teams) beyond just web, and also focuses on the AG-UI protocol for agent-frontend interaction.

LobeChatOn Stork

A sleek, open-source, and feature-rich chat UI designed for developers to build conversational AI applications, offering extensive customization and multi-model support.

LobeChat is a comprehensive open-source chat UI that provides a full application experience, whereas assistant-ui focuses on providing composable React primitives for developers to build their own custom chat UIs. Both offer open-source solutions for AI chat interfaces.

See every assistant-ui alternative, compared→

Related AI Tools

Other tools in this category, matched by shared tags

Pruve.dev Vibedecode Clipper Roomly AI RC Football UseTokenSaver

Visit assistant-ui↗

Connect

𝕏

X / Twitterx.com/LangChainAI/status/1833896540542558217

⌘

GitHubgithub.com/assistant-ui/assistant-ui

💬

Discorddiscord.gg/S9dwgCNEFs