Building A2A Agent using Langchain4J and SpringBootEngineering Blog · April 2026 📦 Spring Boot 4 · LangChain4j · SpringAI A2A Server 🧠 Ollama / Qwen3 🔗 A2A Protocol 1.0 Table of Contents Spring A2A Server AutoConfiguration LangChain4j Agent ... Apr 12, 2026 engineering, ai, architecture, springboot, langchain4j