Sent ahead of everything else in a chat request, it gives high-priority instructions and context covering role, rules, tone, format and boundaries. Compliance is not guaranteed, only steered; in chat and fine-tuning data it is the system turn.
Also called system prompt, metaprompt.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains System message in context, with comparison tables and the common traps.
Terms in this definition
- Role
How an actor normally or expectedly behaves, or the part a person takes in a process. A single actor may hold more than one role.
- FORMAT
A DAX function that turns a value into text according to a format string, for instance "MMMM" to show a month's name. Since the output is text, numeric operations can't use it, and dynamic format strings were introduced to get around that.
- Fine-tuning
Continuing to train a pretrained base model on task examples, through supervised fine-tuning, DPO or RFT, so its weights shift towards a style, format or task. It neither acts as a safety control nor adds new knowledge well.
- Chat message roles
Labels on chat messages: instructions go under system, the person's input under user, the model's previous answers under assistant, and results returned by a called tool under tool (or function).
- TURN
If a direct link can't be made, RDP Shortpath for Windows 365 relays UDP traffic via Microsoft servers on port 3478 instead.
Related terms
- Foundry playground
Interactive space in the Foundry portal where a deployed model can be tried out before any code is written. Users tweak temperature, top_p, max tokens and the system prompt, compare models and export sample code; production traffic does not belong here.