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Prompt

Visual diagram · (in preparation) · Math · (in preparation) · Worked example · 3 difficulty levels.

TL;DR. The input text — instructions, context, examples — given to a language model to elicit a response.

Technical Definition

The input text — instructions, context, examples — given to a language model to elicit a response.

How it works

A prompt can range from a single question to thousands of tokens of system instructions, retrieved documents, and few-shot examples. Because LLMs are extremely sensitive to wording, the same task can produce vastly different outputs depending on prompt design — the discipline known as prompt engineering.

Related Concepts

  • Prompt Engineering — The art of crafting effective input instructions to guide LLM behavior without changing model weights.
  • System Prompt — A high-priority instruction that sets a model's role, tone, and constraints for an entire conversation.
  • Completion — The text a language model generates in response to a prompt.