Prompt frameworks: RTF, CO-STAR, RISEN and the six-part structure
A prompt framework is a checklist of the parts a prompt should contain. Frameworks use different names and different numbers of parts, but they ask for much the same things. Here are the common ones and when each fits.
RTF: Role, Task, Format
The shortest of the common frameworks and a good first habit. Say who the AI should be, what it should do and how the answer should look.
You are a friendly customer-support writer (Role). Reply to the customer message below and offer a refund or a replacement (Task). Use three short paragraphs and no jargon (Format).
Best for quick, single-step requests.
CO-STAR: Context, Objective, Style, Tone, Audience, Response
A longer checklist that separates style from tone and names the audience. Context is the background, Objective is the goal, Style and Tone describe how it should sound, Audience says who reads it, and Response says what form the answer takes.
Context: we are announcing a price change to existing customers. Objective: explain the change and keep them subscribed. Style: clear and concise. Tone: warm and honest. Audience: non-technical small-business owners. Response: an email under 150 words.
Best for writing where voice and audience matter.
RISEN: Role, Instructions, Steps, End goal, Narrowing
Adds the steps to follow and a narrowing part that sets limits. Useful when the order of the work matters.
Role: a senior analyst. Instructions: review the quarterly sales table below. Steps: find the three biggest changes, suggest a cause for each, list what to check next. End goal: a briefing for the sales director. Narrowing: one page, nothing beyond what the data supports.
Best for multi-step tasks such as analysis or planning.
The six-part structure VegaPrompts uses
VegaPrompts builds a prompt from six parts: role, context, objective, instructions, format and constraints. It covers what the shorter frameworks ask for and keeps instructions and constraints separate, so long prompts stay readable.
Which one should you use?
You do not need to memorise any of them. They are checklists: a prompt that answers who, what, for whom, in what form and within what limits covers the same ground.
- A simple one-step request: RTF.
- Writing where tone and audience matter: CO-STAR.
- A multi-step task: RISEN.
- Anything long or reused: the six-part structure.
Framework names, and the wording of each letter, vary between sources.
Skip the writing
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