Last week, finance dropped a screenshot into the group chat: this month’s LLM API bill was ¥5,368, up 4x month-over-month. “Do you tech people not feel anything if you don’t spend money?” That moment I suddenly understood every algorithm team that’s ever had their budget slashed. We run an intelligent customer-service system with three or four large clients. Daily active users aren’t huge, but conversations are extremely long. Some users chat with the bot for hundreds of turns, and every reques...