Elysia is an innovative open-source Python framework developed by Weaviate, designed to elevate Retrieval-Augmented Generation (RAG) from a basic retrieval tool into an intelligent, agentic system with transparent reasoning. A key feature of Elysia is its Decision-Tree Reasoning, which enables users to visualize the model's complete thought process as it interacts with data and tools. Additionally, it incorporates Smart Model Routing, automatically selecting smaller, faster models for simple queries and escalating to more powerful models for complex tasks, thereby optimizing cost efficiency. Rather than providing plain text responses, Elysia delivers Dynamic Data Displays such as charts, tables, and product cards. The framework also learns from user feedback and corrections to enhance its accuracy over time, addressing many of the "black box" challenges associated with traditional RAG systems. For organizations, Elysia facilitates the development of advanced, enterprise-grade data agents, enabling the creation of "Transparent Research Agents" tailored for financial or legal clients. These agents not only provide answers but also disclose the exact data and reasoning path used, which is essential for auditable workflows. Furthermore, Elysia supports the development of "Intelligent Data Dashboards" powered by agents that generate live charts and tables, offering more than just text summaries. As a full agentic framework, Elysia introduces a new level of intelligence, transparency, and cost-efficiency to "chat with your data" solutions.