CO-STAR Prompt Framework Generator
Describe your task — get a structured CO-STAR prompt with Context, Objective, Style, Tone, Audience, and Response sections ready to paste into any chat model.
Related guide: Read on the blog →
What CO-STAR stands for
CContext
Background the model needs: situation, facts, constraints, prior decisions, or source material summaries.
OObjective
The specific goal — verb-first and measurable where possible. What done looks like in one sentence.
SStyle
Writing style: report, narrative, executive memo, tutorial, social post, technical doc.
TTone
Emotional register: formal, friendly, persuasive, empathetic, direct, academic.
AAudience
Who reads the output: role, expertise level, time available, what they already know.
RResponse
Output format: length, sections, bullets vs prose, tables, word limits, language.
Empty template
Context: [situation and facts] Objective: [specific goal] Style: [writing style] Tone: [emotional register] Audience: [reader profile] Response: [format and length]
Filled example
Context: We launch a team project tool next Tuesday. Current users are 200-person agencies using spreadsheets. Objective: Draft a launch email that drives free-trial signups from team leads. Style: Short marketing email — scannable, no jargon. Tone: Friendly and confident, not hype-heavy. Audience: Operations and team leads, busy, skeptical of new tools. Response: Subject line + body under 180 words + single CTA button text.
Generate your CO-STAR prompt
Describe the task or paste a rough draft — get labeled sections plus a combined paste-ready prompt.
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Upload up to 10 images at once on Image to Prompt. Pro includes unlimited batches. Otherwise: $1.99 one-time per batch, or 10 credits.
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Why CO-STAR works for chat prompts
Most failed prompts omit one of six decisions: background context, a specific objective, style, tone, audience, or response format. CO-STAR forces each decision into a labeled line so the model does not guess what you meant by "write something professional."
The framework shines for customer emails, landing page drafts, internal memos, and support replies — anywhere register and reader matter as much as the task itself.
How to use this CO-STAR generator
Type a one-sentence task or paste a rough draft. PromptMake fills all six CO-STAR sections with concrete content, marks missing facts as [ADD: ...] when needed, and adds a combined prose block for models that prefer paragraphs over labels.
Copy the result into ChatGPT, Claude, or Gemini. Edit Context with real data before sending customer-facing output — the generator structures intent; you supply verified facts.
CO-STAR vs RTF and CRAFT
RTF (Role, Task, Format) is a lighter three-part template for quick tasks. CRAFT (Context, Role, Action, Format, Tone) front-loads context and action. CO-STAR adds Style, Audience, and a dedicated Response slot — best when voice and reader profile strongly affect the output.
Many teams keep all three frameworks in a shared doc and pick by task weight: RTF for fast edits, CRAFT for operational briefs, CO-STAR for external comms.
FAQ
What is the CO-STAR prompt framework?
CO-STAR stands for Context, Objective, Style, Tone, Audience, and Response. It structures chat prompts so the model receives background, a clear goal, voice guidance, reader profile, and output format in labeled sections.
Who created CO-STAR?
CO-STAR was popularized by Singapore's GovTech for practical AI adoption. It is widely used for marketing copy, internal comms, and customer-facing content where tone and audience matter.
CO-STAR vs AIDA — which should I use?
AIDA (Attention, Interest, Desire, Action) is a copywriting formula for ads and sales pages. CO-STAR is a general prompt structure for any text task. Use CO-STAR to brief the model; use AIDA inside the Objective or Response section when writing ads.
Does this generator work with ChatGPT and Claude?
Yes. The output is plain labeled text you paste as a user message or fold into a system prompt. It is model-agnostic.
Can I start from a rough draft?
Yes. Paste a messy paragraph or bullet list — the generator expands it into complete CO-STAR sections plus a combined prose version.
Is it free?
Yes — 3 free text generations per day without signup. Sign up for 5 per day. Pro unlocks unlimited runs.
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