A→Z
A2ZAI
Back to Glossary
techniques

System Prompt

Instructions given to an AI model that define its behavior, personality, and constraints.

Share:

Definition

A system prompt is a special message that sets the context and rules for how an AI model should behave throughout a conversation.

Purpose: - Define AI persona - Set behavioral guidelines - Establish constraints - Provide background context - Configure output format

Common Uses: - Role-playing ("You are a helpful coding assistant") - Format specification ("Respond in JSON") - Behavior rules ("Never discuss X") - Expertise framing ("You are an expert in Y") - Tone setting ("Be concise and professional")

Best Practices: - Be specific and clear - Use structured formatting - Include examples - Define edge cases - Test thoroughly

Note: System prompts are typically hidden from users but guide the AI's behavior in every response.

Examples

Custom GPTs use system prompts to define their specific behavior and knowledge domain.

Related Terms

Large Language Model (LLM)

AI models trained on massive text datasets that can understand and generate human-like text.

Context Window

The maximum amount of text a language model can process at once.

Prompt Engineering

The practice of designing effective prompts to get better outputs from AI models.

Want more AI knowledge?

Get bite-sized AI concepts delivered to your inbox.

Free intelligence briefs. No spam, unsubscribe anytime.

Discussion

Browse all termsTake AI 101 Course