langchain-ai/chat-langchain ? reverse-engineered prompt

Build me a web app that acts like a helpful chat assistant for LangChain, LangGraph, and LangSmith docs.

It should have a simple public chat page where people can ask questions and get clear answers based mostly on the official documentation. If the question is about a known issue, it should also check a support knowledge base and mention that when useful. I want it to stay focused on LangChain related questions, and politely refuse or redirect things that are off topic.

Please make it validate any links before showing them, and keep the answers practical and easy to follow. Also include a way for users to give feedback on responses and for the app to handle identity or guest access in a safe way. If you need to, look up the current docs online so the assistant behavior matches the latest LangChain setup.