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assistant-ui review

assistant-ui is an open-source TypeScript/React library of composable primitives and runtimes for building AI chat interfaces in your app.

Updated Nov 1, 2026. Review written Oct 22, 2026 from the project's own sources; usage data refreshed every Monday.

TL;DR

assistant-ui is an open-source TypeScript/React library for building AI chat experiences. It is for frontend developers who want chat UI with streaming, tools and attachments built in. Instead of one monolithic component, assistant-ui gives you composable primitives and runtime adapters for the Vercel AI SDK, LangGraph, LangChain and custom backends.

assistant-ui at a glance

Category
Agent frameworks
Maintained by
assistant-ui (organization, @assistant-ui on GitHub)
License
MIT
Language
TypeScript, MDX, JavaScript
Repository
github.com/assistant-ui/assistant-ui
Website
www.assistant-ui.com
npm package
@assistant-ui/react 0.15.30
Latest release
@assistant-ui/[email protected] on GitHub, Oct 19, 2026
First published
Nov 22, 2023

What assistant-ui does

  • assistant-ui provides composable primitives such as Thread, Message, Composer, ThreadList and ActionBar to build any chat UX.
  • assistant-ui handles streaming, auto-scroll, retries, attachments, markdown, code highlighting, voice dictation, keyboard shortcuts and accessibility.
  • assistant-ui renders tool calls and JSON as React components, collects inline human approvals, and exposes safe frontend actions to the model.
  • assistant-ui connects to backends through runtime adapters for Vercel AI SDK, LangGraph, LangChain, AG-UI, A2A, Google ADK, OpenCode and custom data streams.
  • assistant-ui offers typed runtime APIs, tool schemas, message parts and adapters end to end in TypeScript.
  • assistant-ui supports reasoning, sources, branching and suggestions in its runtime.
  • assistant-ui ships for React, React Native and Ink, with Vue listed as a platform on the homepage.

How it works

You wrap your chat in AssistantRuntimeProvider with a runtime hook such as useChatRuntime, then render components like Thread. useChatRuntime connects to the Vercel AI SDK. Your API route runs the model and the transport streams output back. You can swap in useLangGraphRuntime, useDataStreamRuntime or a custom runtime. The CLI copies UI source into your project. Optional Assistant Cloud stores threads.

How to install and start using assistant-ui

New project with the CLI

npx assistant-ui@latest create

Add to an existing project

npx assistant-ui@latest init

With npm

npm install @assistant-ui/react @assistant-ui/ai-sdk ai

Requirements

  • A React app written in TypeScript or JavaScript.
  • A backend that runs the model, such as a Vercel AI SDK route, LangGraph, or a custom HTTP backend.

First steps

  1. Run the CLI to scaffold a Next.js app or add the styled components to an existing project.
  2. Choose the Base UI (default) or Radix UI flavor for the starter components the CLI copies in.
  3. Wrap the Thread component in AssistantRuntimeProvider using a runtime from useChatRuntime.
  4. Pick the runtime adapter package that matches your backend, such as LangGraph or a custom data stream.

Who assistant-ui is for

  • React developers adding a ChatGPT-style chat interface to their app.
  • Teams building agent frontends on LangGraph, LangChain or the Vercel AI SDK.
  • Developers who want full styling control through composable primitives instead of a fixed chat widget.
  • Apps that need generative UI and human-in-the-loop tool approvals.

Limitations to know

  • assistant-ui is a frontend library; your backend or route still runs the model.
  • assistant-ui is built around React; the main packages are TypeScript/React.
  • Managed thread history, telemetry and file storage require the separate Assistant Cloud service.
  • The OpenCode adapter cannot unarchive threads, because OpenCode cannot unarchive a session.

Is assistant-ui growing? Usage data

In the week of Oct 25–31, 2026, assistant-ui ranked #86 on the Devtoolwatch Board and #7 in Agent frameworks, with a momentum score of 67 out of 100. Its main package had about 2.8M downloads that week, +16% against its own 4-week average.

New GitHub stars per week for assistant-ui12 weeks from Aug 9, 2026: 163, 116, 139, 101, 107, 89, 107, 82, 89, 130, 145, 149 new stars, an average of 118 a week.Aug 9week of Oct 25
New GitHub stars per week for the last 12 weeks, from GitHub's stargazer history (today's stargazers by the week they starred).
Show the weekly numbers
New GitHub stars per week for assistant-ui
Week ofNew stars
Aug 9, 2026163
Aug 16, 2026116
Aug 23, 2026139
Aug 30, 2026101
Sep 6, 2026107
Sep 13, 202689
Sep 20, 2026107
Sep 27, 202682
Oct 4, 202689
Oct 11, 2026130
Oct 18, 2026145
Oct 25, 2026149

On Hacker News

The Board ranks tools by four signals each week: new stars, new stars for the repo's size, added downloads and download growth beyond the market. How the ranking works.

assistant-ui alternatives

Other AI agent frameworks on the Board in the week of Oct 25–31, 2026, by momentum:

Agent frameworks ranked by momentum, the week of Oct 25–31, 2026
RankToolStarsDownloads/wk
#1Harness²Harness² is a Python framework from Google Research for recursive agent harnessing, refining an agent's prompts, tools, memory and…21.7k–
#2HyperFramesHyperFrames is an open-source framework that turns HTML, CSS, media, and seekable animations into deterministic MP4 videos, built for AI…76.6k1.5M
#3AgentScopeAgentScope is a Python agent framework with an SDK for building ReAct agents and an agent service backend with a web UI.35k51.4k
#4AG-UIAG-UI is an open, event-based protocol that standardizes how AI agents connect to user-facing frontend applications.16.9k4.6M
#5LangGraphLangGraph is a low-level orchestration framework and runtime for building, managing, and deploying long-running, stateful agents in…44.2k18.5M
#6BifrostOpen-source, high-performance AI gateway that works as your LLM gateway, MCP gateway and agent gateway. One OpenAI-compatible API for…9.3k–

All AI agent frameworks, ranked

Recent assistant-ui releases

assistant-ui FAQ

Is assistant-ui free and open source?

Yes. assistant-ui's source code is on GitHub (assistant-ui/assistant-ui) under the MIT license, so you can use it for free. Its website also links to a pricing page (https://www.assistant-ui.com/pricing) for any paid plans.

How do I install assistant-ui?

Run npx assistant-ui@latest create. The install section above has the other options from the project's README.

Is assistant-ui still maintained?

Yes. The assistant-ui/assistant-ui repository was last updated on Oct 21, 2026, and the latest release, @assistant-ui/[email protected] on GitHub, came out on Oct 19, 2026.

How popular is assistant-ui?

assistant-ui has 12.9k GitHub stars as of Nov 1, 2026. It gained 149 new stars in the week of Oct 25–31, 2026, against a 12-week average of 118 a week. Its main package had about 2.8M downloads that week, +16% against its own 4-week average. That made it #7 among AI agent frameworks on the Devtoolwatch Board.

assistant-ui vs CopilotKit: how do they compare?

assistant-ui and CopilotKit are both tracked by Devtoolwatch as AI agent frameworks. assistant-ui has 12.9k GitHub stars and CopilotKit has 38.4k. In the week of Oct 25–31, 2026, assistant-ui's main package had 2.8M downloads and CopilotKit's had 653.6k. CopilotKit is an open-source framework that connects apps to AI agents with chat, generative UI, shared state, and human approvals. CopilotKit review.

What are the best alternatives to assistant-ui?

Other AI agent frameworks on the Devtoolwatch Board in the week of Oct 25–31, 2026, by momentum: Harness² (#1), HyperFrames (#2), AgentScope (#3), AG-UI (#4), LangGraph (#5). The alternatives table above has their numbers.

Is assistant-ui open source?

Yes. assistant-ui is an open-source TypeScript/React library released under the MIT license. Assistant Cloud is an optional managed service for thread persistence and analytics.

Which backends does assistant-ui work with?

assistant-ui has adapters for the Vercel AI SDK, LangGraph, LangChain, AG-UI, A2A, Google ADK, OpenCode and custom data-stream backends. It can also extend to any custom HTTP backend.

Which model providers does assistant-ui support?

assistant-ui supports OpenAI, Anthropic, Google Gemini, Mistral, Perplexity, AWS Bedrock, Azure, Fireworks and Ollama out of the box. It also supports community providers through the AI SDK.

Can I customize the assistant-ui chat interface?

Yes. assistant-ui gives you primitives you compose and style yourself. The CLI copies the UI source into your repo, starting from a shadcn/ui theme in Base UI or Radix UI flavor.

How does assistant-ui persist chat threads?

assistant-ui persists threads through the optional Assistant Cloud. Assistant Cloud provides managed thread history, telemetry and file storage, so sessions survive page refreshes.

Sources

  1. assistant-ui/assistant-ui on GitHub
  2. assistant-ui README
  3. @assistant-ui/react on npm
  4. assistant-ui website
  5. Release @assistant-ui/[email protected] (Oct 19, 2026)
  6. Release @assistant-ui/[email protected] (Oct 19, 2026)
  7. Release @assistant-ui/[email protected] (Oct 19, 2026)
  8. Hacker News: Assistant-UI is an open-source AI chat component for React
  9. Devtoolwatch Board, the week of Oct 25–31, 2026

assistant-ui README badge

Maintainers can show the tool's weekly Board rank in their README:

Devtoolwatch badge for assistant-ui

[![Devtoolwatch](https://index.devtoolwatch.com/badge/assistant-ui.svg)](https://index.devtoolwatch.com/tools/assistant-ui/)

How this page is made: Devtoolwatch writes each review from the project's README, releases, package metadata and website, with an AI model, then checks every claim against the source it cites and drops what the sources don't support. The numbers come from Devtoolwatch's daily GitHub snapshots, GitHub's stargazer history, and the npm and PyPI download APIs. Spotted an error? Email [email protected].