lm-sys/FastChat
FastChat is an open platform for training, serving, and evaluating large language model based chatbots, featuring multi-model serving, extensive model support, and large-scale evaluation datasets.
Awesome AI Agents › Chatbot Platforms
cossistantcom/cossistant
Cossistant is an open-source customer support stack aimed at developers building SaaS products in the React ecosystem. Instead of shipping a fixed, styled chat bubble, it exposes headless components and hooks so the widget markup and styling are written by the host application, while the library supplies state, real-time transport and backend behaviour. The repository describes a code-first, API-driven approach with documentation written to be readable by both developers and AI coding tools. Two npm packages are published from the monorepo: @cossistant/react, the SDK with headless hooks and primitives, and @cossistant/next, which adds Next.js-specific bindings and utilities. Beyond the client widget the project ships the complete backend infrastructure needed to run support conversations, so a team can self-host the service rather than relying on a hosted vendor. The agent aspect comes from configurable AI support agents that answer customer conversations, which can be customised per deployment alongside human handoff. The technology stack is a Turborepo monorepo running on Bun, with React and Next.js on the front end, TypeScript throughout, Hono serving the API, tRPC for typed client-server calls, Drizzle ORM over Postgres, Better Auth for authentication, TailwindCSS for the example styling, WebSockets for live message delivery and Docker Compose providing Postgres and Redis for local development. Licensing is dual: the code is AGPL-3.0 for non-commercial use, and commercial deployments require a separate licence obtained by contacting the maintainers. The project participates in the Vercel open-source program and runs its own open-source friends program. It suits startups and product teams that want an embeddable support channel with AI-assisted replies under their own control, with full ownership of the data and the ability to shape the interface to match an existing design system.
https://github.com/cossistantcom/cossistant
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Open-source desktop client that runs an OpenClaw agent locally and bridges it into WeChat, Feishu, Slack and Discord through a graphical setup, with bring-your-own-key and OAuth model access.
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langchain-ai/streamlit-agent
Reference implementations of various LangChain agents as interactive Streamlit applications demonstrating conversational AI capabilities and integrations.