System Prompts

---
tags: [Beginner]
---

# System Prompts

> The system prompt sets the rules of the game — persona, constraints, and output format — for
> the whole conversation. It's the most durable way to shape a model's behavior.

## Overview

Every message you send has a role. The **system prompt** is special: it's the standing
instruction the model treats as its operating context for the entire conversation, separate from
individual user turns. Get it right and your app behaves consistently; get it wrong and you'll
fight the model with every turn.

## Learning Objectives

By the end of this page you will be able to:

- Distinguish the system prompt from user/assistant messages.
- Write a system prompt that reliably controls persona, scope, and format.
- Understand the security limits of system prompts.

## Theory

### Where it sits