Chainlit
lastmod 2026-11-10created 2026-01-133 edits
Chainlit is an open-source framework for building the chat UI of LLM-based conversational AI applications in a few lines of Python. You write it by attaching decorators to functions that run when a message is received, and it has the elements a chatbot needs built in, such as streaming responses, visualization of intermediate steps (chain and tool calls), file uploads, and user feedback collection. It integrates with LLM libraries such as LangChain and LlamaIndex, and unlike the general-purpose data app tools Streamlit and Gradio, it specializes in conversational interfaces.
Build Conversational AI in minutes