ADK Java — Plan-and-Execute Pattern

Why it matters

Plan-execute shapes complex task handling. Cheaper than pure ReAct for known workflows.

The architecture

Planner: makes step list.

Executor: runs each step, possibly with tools.

Replan: if step fails.

How it works end to end

Planner: uses strong LLM.

Executor: cheaper LLM for simple steps.

Replanning: on failure signals.