What is a system prompt?

By the Variask team · Updated

Definition

A system prompt is the hidden instruction an AI product gives its model before the user's question, setting its role, tone and rules. It shapes how answers are written, such as whether to name brands or cite sources, but users do not see it.

How it works

  • The product sends the system prompt with every conversation.
  • It can tell the model to be concise, cite sources or stay neutral.
  • Different products wrap the same model with different system prompts.
  • This is one reason the same model can answer differently in different apps.

What it means for brands

  • You cannot change an AI product's system prompt, but you can change the sources it reads.
  • Expect differences between apps that use the same model.

Questions

System prompt:
common questions

No. They are set by the AI product. Work on your sources and pages instead.

Partly. Different instructions, search tools and settings all play a part.

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