System Prompt Builder
Design robust system instructions for AI models by clearly defining persona, rules, and output formats.
System Prompt Builder
Assemble stronger prompts with structure, variables, custom sections, and inline quality feedback.
Persona / Role
Who should the model be?
0 words0 chars
Core Instructions
What should it actually do?
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Rules & Constraints
What must it never do?
0 words0 chars
Output Format
How should answers look?
0 words0 chars
Examples (Few-Shot)
Show the expected behavior
0 words0 chars
Add custom section
Quality Check
Prompt StrengthNot started
0 / 100
Words
0
Characters
0
Tokens
0
GPT-4o
~0
Claude
~0
Llama
~0
Persona / role defined
Core instructions defined
Rules & constraints defined
Output format defined
Example / few-shot provided
Custom context sections (optional)
All variables filled
Recommended length 50–1200 words
Add a persona to anchor behavior.
Specify core instructions for clearer direction.
Include a few explicit rules or constraints.
Define the expected output format.
Provide a short example for better behavior.
Final System PromptMarkdown
Fill out the sections to generate your system prompt...