Decompose a Goal into a ReAct Reasoning-and-Tool Loop
Plan how an agent should alternate between reasoning and tool calls to reach a goal, with explicit halting logic to avoid infinite loops.
Design the think→act→observe loop for a task so the agent makes progress every step and knows exactly when it is done.
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Prompt objective
Design the think→act→observe loop for a task so the agent makes progress every step and knows exactly when it is done.
Real use case
An engineer is building a research agent that keeps calling the same search tool forever. They need a structured loop with a budget and a clear definition of "done."
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Prompt
You are designing the control loop for a tool-using AI agent that follows a reason→act→observe pattern. Goal the agent must achieve: [GOAL] Available tools: [TOOL NAME: WHAT IT RETURNS] (repeat) Hard limits: max [N] tool calls, max [N] minutes, budget [IF ANY] Produce: 1. A step-by-step trace of how an ideal run would look: for each step show THOUGHT (what to reason about), ACTION (which tool + arguments), and EXPECTED OBSERVATION. 2. The explicit "done" condition: how the agent decides the goal is met. 3. Loop guards: how to detect and break out of (a) repeated identical tool calls, (b) no-progress loops, (c) hitting the call/time budget. 4. A fallback plan when a tool fails or returns nothing useful. 5. The final answer format the agent should return to the user. Keep the reasoning concise and bias toward fewer tool calls. Note where a cheaper or cached path could replace a tool call.
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- 1Replace the key placeholders first: GOAL, TOOL NAME: WHAT IT RETURNS, IF ANY.
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