System prompt
High-priority instructions supplied by the application operating a model.
What System prompt does not show
It shapes behavior but is not an impenetrable security boundary against conflicting or injected content.
Related terms in Models and generation
How a model produces text, what its training and decoding controls change, and what none of them can prove about a source.
Autoregressive model · Transformer · Attention · Self-attention · Parameter · Inference · Pretraining · Fine-tuning · Supervised fine-tuning · Instruction tuning · RLHF · Preference optimization · Knowledge distillation · Quantization · Mixture of experts · Multimodal model · Vision-language model · Small language model · Tokenizer · Temperature · Top-p sampling · Deterministic decoding · Developer message · Tool call · Function calling · Structured output · Constrained decoding · Chain of thought · Reasoning trace · Context caching · Context compaction · Model routing · Model drift · Model version
Questions about System prompt
What is System prompt?
High-priority instructions supplied by the application operating a model.
What does System prompt not show or guarantee?
It shapes behavior but is not an impenetrable security boundary against conflicting or injected content.
Which area of the glossary does System prompt belong to?
Models and generation: How a model produces text, what its training and decoding controls change, and what none of them can prove about a source.
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