Free system prompt builder — assemble battle-tested system prompts for GPT, Claude, and Gemini with proven patterns.
Was System Prompt Builder useful?
Your vote helps us prioritize improvements.
The QuickToolz System Prompt Builder assembles production-ready system prompts using patterns proven across thousands of agents — role, capabilities, tone, format, tool-use rules, refusals, and example I/O. Pick the patterns that apply, fill in the blanks, and copy a clean, structured prompt ready for GPT, Claude, or Gemini.
Role + persona definition
Allowed/disallowed topics
Output schema (JSON, Markdown, plain text)
Tool-use rules (when to call, when not to)
Refusal language
Few-shot examples
Everything you need, nothing you don’t. Built for speed and simplicity.
Toggle each section in or out.
Adjusts formatting for GPT, Claude, or Gemini conventions.
Refusal language, safety rails, and tone shipped by default.
Everything you need, nothing you don’t. Built for speed and simplicity.
Customer support, code reviewer, data extractor, etc.
Got questions? We’ve got answers. Common questions about System Prompt Builder.
Role, tone, format, refusals.
Cleanly structured, ready to paste into your platform.
System prompt builder
Prompting rule
Keep system prompts short, specific, and stable. Put variables, examples, and user-specific context in the user message whenever possible — not in the system layer.