Glossary
System Prompt
A system prompt is a high-priority instruction supplied by an AI application to define the assistant’s role, boundaries and behavior. Users typically do not control it, and it can affect tone, tool use, source handling and which requests the application will answer.
In plain terms
It is the application’s standing instruction to the model before the user asks anything.
Why it matters
Different products can produce different answers from similar models because their system instructions and connected tools differ.
How to apply it
- Test visibility by product, not only by underlying model family.
- Record product mode and settings where possible.
- Do not infer hidden system instructions from one response.
Example
Two assistants using related models return different vendor lists because one is instructed to browse and cite sources while the other is not.
Sources
Related reading
Related terms
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