Klarna, a leader in fintech, has transformed global commerce through its consumer-centric, AI-powered payment and shopping solutions, boasting over 85 million active users and 2.5 million daily transactions. The company addresses the challenge of scaling customer support and handling escalations by utilizing an AI Assistant powered by LangGraph and LangSmith, which has significantly improved efficiency by performing tasks equivalent to 700 full-time staff. This AI Assistant, enhanced by controllable agent architecture, context-aware intelligence, and test-driven development, has reduced average customer query resolution time by 80% and automated approximately 70% of repetitive support tasks, allowing customer service agents to focus on complex interactions. The advanced prompt optimization and meta-prompting features have further improved the accuracy of root cause identification, leading to a notable reduction in customer escalations and empowering Klarna's teams to deliver superior customer experiences globally.