RAG systems combine a vector database with a large language model (LLM) to achieve optimal performance, but mastering this requires deeper understanding and fine-tuning beyond basic setups. Rerankers are specialized components that refine search results in a second evaluation stage, improving the quality and ranking of outputs. Fine-tuning rerankers is a logical progression after working with embeddings and offers a powerful approach to enhancing how systems interpret and prioritize information. A Cross-Encoder model can be used for sentence pair classification tasks, including reranking search results, allowing deeper interaction between input texts.