AI Agent Platform Architecture integrates Next.js frontend, NestJS backend, and LangGraph orchestrator to coordinate intelligent agent workflows. The NestJS backend routes requests through Keycloak authentication, manages state in PostgreSQL and Redis, and delegates AI reasoning to a FastAPI RAG Service backed by a vector database. Langfuse and Elastic APM provide observability across the entire stack, enabling teams to monitor agent performance, latency, and error rates in production. This layered design separates concerns—presentation, application logic, authentication, data persistence, and AI reasoning—making it easy to scale individual components independently. Fork this diagram on Diagrams.so to customize it for your LLM application, add additional services, or export as .drawio for documentation.