Spring AI's defaults are built for a fast start; they do not guarantee a low monthly cost. Shipping an LLM feature is easy — making it cost-efficient is not. This series shows the spots where money leaks, along with the control that closes each one. Spring AI 2.0 reached GA on 12 June 2026 . It needs Spring Boot 4 , moves the tool-calling loop out of the ChatModel , adds tool search, and extends structured outputs. Tool search and the extended structured-output controls point in the sam...