Prompt Glossary
A prompt is the input given to a model or agent: the user’s request, the surrounding instructions, examples, files, retrieved context, tool results, and constraints that shape the answer. In casual use, prompt often means the sentence typed into a chatbot. In agentic systems, it is the whole input layer.
Prompting matters because models are highly context-sensitive. The same model can behave very differently when the task is framed as a question, a role, a workflow, a checklist, a set of examples, or a tool invocation. Good prompting is therefore less like magic words and more like good specification: making the task, audience, constraints, and success condition visible.
The system prompt is the higher-priority version of this layer. Ordinary prompts ask for work. System prompts define the operating frame in which the work is done.