A simple API call is sufficient when: your task is single-step, inputs fit in the context window, you need one model's output, and failure handling is not critical. AI orchestration is needed when: your workflow requires multiple steps (retrieve, analyse, generate, validate), you need to route between models based on task complexity or cost, your agent uses tools that produce results it needs to reason about, you need to maintain state across a conversation or workflow, or failures in one step need graceful fallback rather than a full error.