ReAct (Reason + Act) Pattern

ReAct (Reason + Act) alternates between reasoning, taking a tool action, observing the result, and reasoning again.

The loop continues until a goal is reached or constraints stop progress.

It is especially useful when the agent must gather information from systems before deciding what to do next.

ReAct reduces hallucination by encouraging “look before you leap” behavior: observe real system state.

It makes troubleshooting easier because each action is tied to an observation and an updated decision.

Combined with tool boundaries and guardrails, ReAct becomes a controlled, auditable operating loop.

• Unlimited loops without budgets/timeouts, causing runaway cost or repeated actions.
• Using ReAct without tool auditability (actions become invisible).
• Not capturing observations in a structured way, making logs hard to analyze.
• Treating “reasoning” as a replacement for verification; observations still need validation.

• Copyl enables controlled action loops through explicit tools and governed integrations.
• Policies can limit what actions are allowed and when, ensuring loops do not exceed constraints.
• Auditability captures the sequence of actions and outcomes for review and compliance.

• Tool-Using Agent Pattern
• Memory-Augmented Agent Pattern
• Guardrail-First Agent Pattern
• Retry / Self-Healing Agent Pattern
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