PromptingBeginner

Specify Output Format Explicitly

Tell Claude exactly what structure you want: JSON, Markdown, TypeScript types, numbered lists—avoid post-processing by baking format into the prompt.

jsonformatstructured-output

The Strategy

Unspecified output formats force you to write parsing code. Explicit format instructions mean Claude's output slots directly into your application or workflow.

prompt.txt

<task>
Extract all action items from the meeting notes below.
</task>

<notes>
[Paste notes here]
</notes>

<output_format>
Return a JSON array. Each item must have:
- "owner": string (name of the person responsible)
- "action": string (what they need to do)
- "due": string (due date, or "unspecified")
- "priority": "high" | "medium" | "low"

Return ONLY the JSON array—no markdown fences, no explanation.
</output_format>

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PromptingBeginner

Use XML Tags for Structure

Claude is specifically trained to recognize and parse XML tags to separate instructions from content. Wrapping your prompt in named sections removes ambiguity.

xmlstructureclarity

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PromptingBeginner

Use Negative Constraints

Tell Claude what NOT to do. "Do not add comments", "Do not use any external libraries" — negative constraints are just as powerful as positive ones.

constraintsguardrailsfocused-output

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