Dictionary term
System Prompt
Also called system message
PromptingBeginner
A system prompt is a top-level instruction that sets a model's role, rules, and behavior before the user's messages are processed.
In plain English
A system prompt is the standing instructions you give an AI before the conversation starts: who it is, what it may do and how it should answer.
Analogy
Like the job description and ground rules you give an employee before they start handling customers.
Why it matters
It is where you lock in tone, format, and guardrails for every AI step, keeping automated outputs consistent across runs.
In practice
"You are a polite booking assistant. Only answer using the provided business hours."
Related terms
Sources
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