What is the difference between an AI system prompt and a user prompt?

FireTail helps you inventory and analyze AI prompts by identifying their role in shaping model behavior and outputs. Prompts are categorized to distinguish between those defined by the system and those provided by the user.

AI System Prompt

An AI system prompt is a predefined instruction given to the AI model by the platform or service provider. It defines the model's default behavior, tone, and guardrails.

Purpose:

• Sets the AI's persona (e.g., assistant, advisor, bot).
• Establishes behavioral rules (e.g., formal tone, avoid speculation).
• Embeds safety, compliance, and ethical boundaries.

Example:

"You are a helpful assistant. Do not make assumptions and avoid generating unsafe content".

User Prompt

A user prompt is the direct input or query provided by an end user. It tells the model what task to perform or question to answer.

Purpose:

• Asks a question or gives an instruction.
• Directly shapes the AI's response based on the user's intent.

Example:

"List the top OWASP API security risks."