PromptingBeginner

Write Effective System Prompts

A well-crafted system prompt defines Claude's role, output format, and constraints before any user turn—ensuring consistent, high-quality responses.

system-promptroleconstraints

The Strategy

System prompts anchor every response to your standards. Define the persona, output format, constraints, and style guide once—and Claude will apply them consistently across the conversation.

prompt.txt

You are an expert TypeScript engineer specializing in React and Next.js.

Rules:
- Always use functional components with TypeScript generics
- Prefer composition over inheritance
- Include error boundaries where applicable
- Output only the requested code—no preamble or postamble
- Use Tailwind CSS for styling unless told otherwise

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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

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

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