react prompting
**ReAct prompting** is the **reasoning-and-action prompting framework where the model alternates between internal thought steps and external tool actions** - it enables grounded problem solving in environments requiring retrieval or computation.
**What Is ReAct prompting?**
- **Definition**: Prompt format that interleaves reasoning traces with explicit action calls and observations.
- **Loop Pattern**: Think, act, observe, and continue until a final answer is produced.
- **Tool Scope**: Can invoke search, calculators, code execution, databases, or APIs.
- **Control Requirement**: Needs safe action schema and validation of tool outputs.
**Why ReAct prompting Matters**
- **Grounding Benefit**: External observations reduce reliance on unsupported internal recall.
- **Task Coverage**: Supports multi-step tasks requiring both reasoning and information retrieval.
- **Error Reduction**: Tool verification can catch reasoning assumptions early.
- **Agent Capability**: Forms a practical basis for LLM-powered workflow automation.
- **Traceability**: Action-observation chain improves auditability of decision process.
**How It Is Used in Practice**
- **Action Schema**: Define strict tool-call formats and allowed action types.
- **Observation Handling**: Parse tool results and integrate them into next reasoning step.
- **Safety Guardrails**: Apply tool permissions, timeout limits, and output validation checks.
ReAct prompting is **a core architecture pattern for tool-using LLM agents** - alternating reasoning with grounded actions improves reliability on tasks beyond pure text generation.