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ReAct
Combines reasoning with acting through external tool use
In 30 seconds
- What
- Agent loops through thought, calls external tools, observes results, then reasons on new data to decide next action.
- When to use
- Tasks requiring real-time information lookup, verification, or multi-step tool chains where each step depends on live feedback.
- Watch out
- Tool calls can fail or return stale data, forcing the agent into retry loops or hallucinated recovery attempts.
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ReAct: Overview
Combines reasoning with acting through external tool use
- Thought → Action → Observation loop
- Integrates external tools
- Dynamic strategy adaptation
- Real-time environmental feedback
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References
The papers, specifications, and repositories this pattern is based on.
- ReAct: Synergizing Reasoning and Acting in Language Models (Yao et al., 2022)arXiv:2210.03629
- Chain-of-Thought Prompting Elicits Reasoning in Large Language Models (Wei et al., 2022)arXiv:2201.11903
- Toolformer: Language Models Can Teach Themselves to Use Tools (Schick et al., 2023)arXiv:2302.04761
- WebGPT: Browser-assisted question-answering with human feedback (Nakano et al., 2021)arXiv:2112.09332
- LangChain ReAct Agent Documentation