Prompt

A prompt is the instruction, question or information you give an artificial intelligence system to tell it what you want it to do.

If you have ever typed a question into ChatGPT, you have already written a prompt. The prompt is the starting point of the conversation — the message that sets the task. Everything the AI produces is shaped by what you asked and how you asked it, which is why the same model can give a vague, unhelpful answer to one request and a precise, useful answer to a slightly different one.

Prompts range from the very simple to the quite detailed. A simple prompt might be a single line — 'summarise this article' — while a more useful one adds context and constraints: 'summarise this article for a busy manager who needs the three key decisions and any deadlines, in under 150 words, in a neutral tone.' The second version gives the model enough to aim at, and the result is usually closer to what you actually wanted.

What makes a prompt useful is not a secret formula but a few clear ingredients: enough context for the model to know the situation, a clear statement of the desired output, any constraints (length, tone, format, what to include or avoid), and, often, the role you want it to take ('explain this as if to a curious beginner'). Follow-up prompts matter too — you can refine a result by asking the model to shorten, rephrase, add a section or correct something, and a short back-and-forth frequently beats one perfect opening request.

It is worth resisting the idea that there is one 'perfect' prompt. In practice, good prompting is iterative: you try, see what comes back, and adjust. Clear, specific, well-contextualised requests tend to work better than vague ones, but the best prompt for a task is usually discovered by working with the model rather than copied from a list.

One quiet but important habit: because an LLM's AI hallucination risk rises when you ask it for specifics it cannot reliably know, a good prompt often includes an instruction to say when it is unsure — for example, 'if you're not certain, tell me rather than guessing.' The prompt is not just a task; it is also where you set the expectations that keep the result trustworthy.