Do agents plan explicitly or should we let them just react?
hardAnswer
- Depends on task complexity.
- Short tasks (2-4 steps): pure ReAct works well; explicit planning adds overhead.
- Long / complex tasks (10+ steps): explicit planning helps — the LLM writes a plan first, then executes each step, replanning as needed.
- Frameworks: Plan-and-Execute (LangGraph), Reflexion, LATS (LLM tree search).
- Trade-off: plans can become rigid or hallucinated; hybrid = plan then re-plan every K steps.
- Reasoning models (o1, R1) do implicit planning inside their thinking tokens.
Check yourself — multiple choice
- Never plan
- Short tasks: ReAct suffices; long tasks: explicit plan + execute + replan; reasoning models plan implicitly in thinking tokens
- Always plan
- Only classification
Planning: ReAct for short; explicit plan-and-execute + replan for long; reasoning models plan implicitly.
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