Guide
What is a System Prompt?
Instructions that define LLM behavior and personality.
A system prompt is a set of instructions given to an LLM that defines its role, behavior, constraints, and output format. It's separate from user messages and persists across the conversation.
System Prompt Components
- Role: Who the AI is (e.g., "You are a helpful assistant")
- Constraints: What it should/shouldn't do
- Format: How to structure responses
- Context: Background information
Best Practices
- Be specific and explicit
- Include safety constraints
- Define output format clearly
- Test with adversarial inputs
Can users override system prompts?
Prompt injection attacks attempt this. Use input validation, output monitoring, and guardrails to protect system prompt integrity.
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