A system prompt is a special message sent at the start of a conversation in modern Chat APIs that gives the model a persistent role, tone, and set of rules. Unlike user messages, its effect carries through the entire conversation and frames every subsequent request. Popularized by OpenAI's Chat Completions API, the concept then became standard across Anthropic, Google, and other providers. In production it's the primary lever for shaping product behavior, and a well-written system prompt often substitutes for Fine-tuning.
MEVZU N°124ISTANBULYEAR I — VOL. III
Glossary · Beginner · 2022
System Prompt
A special message at the start of a conversation that sets the model's persistent instructions and role.
- EN — English term
- System Prompt
- TR — Turkish term
- Sistem Promptu