AI Glossary / System prompt
⌨️ Prompts
System prompt
A hidden instruction that gives the model a role and rules for the entire conversation.
A system prompt is an instruction set placed "above" the conversation - usually invisible to the user - that gives the model its role, tone, and rules for the entire dialogue. This is where you write things like: "you are a customer service assistant for company X, you respond in English, you do not provide legal advice." For AI application developers, the system prompt is the primary tool for controlling model behavior. For users, it's important to know that every chat has this hidden layer - it's what makes the same model behave completely differently across different products.
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