Large Language Models (LLMs) such as GPT-4 have significantly advanced natural language processing (NLP), with open-source LLMs like Llama 2, Falcon, OPT, and Yi gaining traction for their accessibility, security, and customization benefits. OpenLLM and LlamaIndex are two platforms that, when used together, enable the creation of AI-driven applications by facilitating the deployment and management of LLMs and the retrieval of domain-specific data. OpenLLM allows developers to fine-tune, serve, and monitor LLMs in various applications, while LlamaIndex connects these models to specific data needs, enhancing the ability to build intelligent query-response systems. The integration of these tools enables the development of AI solutions tailored to specific data contexts, crucial for effective query responses. The article demonstrates setting up an environment for employing these platforms, creating a simple completion service, and enhancing it into a comprehensive query-response system using LlamaIndex to improve model knowledge with domain-specific data. Ultimately, the discussion emphasizes the importance of customizing AI tools to match specific requirements, showcasing the potential of OpenLLM and LlamaIndex in building intelligent systems.