Advanced AI customer service goes far beyond FAQ chatbots. Architecture components: 1) Intent classification: fine-tuned BERT or LLM-based classifier identifying 50-100 specific intents (billing_question, cancellation_request, technical_issue). 2) Entity extraction: NER for order numbers, product names, dates. 3) Context management: maintain conversation history and customer profile across channels (email, chat, phone). 4) Sentiment scoring: real-time analysis routing high-frustration customers to senior agents. 5) Knowledge base retrieval: RAG over product documentation, policies, and FAQs for accurate, current answers. 6) CRM integration: pull order history, past interactions, account tier to personalize responses. 7) Escalation logic: multi-factor scoring combining sentiment, issue complexity, customer tier, and resolution confidence. 8) Post-interaction analysis: automatically categorize resolved issues, identify knowledge gaps, measure CSAT correlation with AI vs human handling. Production metrics: containment rate (% resolved without human), CSAT score, average handle time, escalation rate.