Booking.com is leveraging AI and machine learning to enhance user experiences by implementing various agent and generative AI (GenAI) use cases, such as the AI Trip Planner chatbot, free-text filters, and search functionalities. Chana Ross, the Machine Learning Manager, highlights the importance of tool descriptions in reducing hallucinations and the integration of product managers and UX writers in prompt optimization to improve user interaction. To ensure the effectiveness of large language models (LLMs), Booking.com employs evaluation bundles that assess hallucination, relevancy, and clarity, which are crucial as LLMs can drift over time. The company combines LLMs with deterministic services to maintain personalized yet auditable results, using Arize AX for production monitoring and evaluations to track and improve agent performance. Ross emphasizes starting with simple solutions, understanding the problem thoroughly, and iterating with evaluative feedback to efficiently bring agents to production, while also stressing the importance of monitoring and metric dashboards for ongoing system oversight.