The TypeScript AI Agent Architecture I Would Use in 2026

Most AI apps do not fail because the model is bad. They fail because the system surrounding the model lacks structure. The first version usually starts the same way. A user sends input, the app calls an LLM, and the response is returned. That is enough for a demo, but the moment the system needs to do anything real, the design starts to break. A real AI system does more than generate text. It may need to call APIs, use tools, remember context, validate outputs, retry on failures, ask for human a