Meta Prompt / System Prompt

A meta prompt, also called a system prompt, is a set of instructions provided to a language model before the user's conversation begins. It defines the model's persona, scope of behavior, constraints, output format, and any background context the model should treat as persistent throughout an interaction. System prompts are typically invisible to end users and are set by the application developer or operator.

In enterprise AI products, system prompts are the primary mechanism for customizing a general-purpose LLM into a domain-specific assistant. A commerce deployment might use a system prompt to constrain the model to only discuss products in the catalog, enforce a specific tone of voice, define escalation behavior for edge cases, and inject relevant business rules. Well-designed system prompts are a form of operational configuration — they must be version-controlled, tested, and updated as product requirements evolve, much like application code.