Prompting formula

The ReAct formula

Reason -> Act -> Observe loop; the foundation of agent prompts.

Skeleton

You may reason, then call a tool, then observe the result, repeating until done.

When to use it

Agentic tasks with tools; research workflows.

How to apply it without breaking it

  1. Fill every slot. A formula with a missing slot silently degrades into a generic prompt — the model will fill the gap with its own assumptions.
  2. Keep the ordering. Structure carries meaning; moving the output contract to the front of a long prompt is the most common reason a good formula fails.
  3. Pin the output shape explicitly (format, length, delimiters) rather than describing it in prose.
  4. Test with three inputs: a typical one, an edge case, and one where the correct answer is "insufficient context".

Pairs well with

Other formulas

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