JoshuaC215/agent-service-toolkit ? reverse-engineered prompt

Build me a simple but complete AI agent app that I can run locally and also deploy later.

I want a LangGraph based agent service with a FastAPI backend, plus a Streamlit chat app that talks to it. The chat should feel polished, support streaming responses, and let me see previous conversations. If you can, make it easy to plug in more than one agent and switch between them by URL, and expose a small info page that shows what agents and models are available.

Please include a clean way to configure API keys and settings with environment variables, and make it work well with Docker so I can start everything with one command. It would be great if the app also supports voice input and output, basic feedback on responses, and an optional RAG style assistant using a vector store. Use current docs online if you need to, and keep the code organized so I can customize the agent behavior later.