COAST Prompt Framework

COAST = Context, Objective, Actions, Scenario, Task. A five-part framework for complex prompts where background, constraints, and full situation context are necessary for a useful AI response.

When to Use COAST

Use the COAST framework when:

The task involves business strategy, marketing planning, or research where context heavily shapes the output.
A generic answer would be useless — the AI needs to know your specific situation, constraints, and goals.
Multiple stakeholders, budgets, timelines, or team constraints affect what the response should recommend.
You need a concrete deliverable — a plan, document, or structured output — not just general advice.

When Not to Use COAST

Simple, quick tasks — use the TAG framework instead.
Image generation prompts — visual models require different prompt structures focused on style, medium, and composition.
Step-by-step workflow tasks — use the RISE framework for ordered procedural outputs.

COAST Framework Template

Context: [Background information and setting]
Objective: [What you want to achieve]
Actions: [Specific actions or steps the AI should take]
Scenario: [Specific situation, constraints, or parameters]
Task: [The specific deliverable or output]

Example: Marketing Strategy

Before (weak prompt):

Create a marketing plan

After (structured prompt):

Context: Early-stage B2B SaaS startup, project management tool, currently at 50 paying customers
Objective: Increase trial signups by 30% over the next 90 days
Actions: Identify 3 top acquisition channels, outline content topics, suggest budget allocation
Scenario: Total marketing budget of $5,000, team of 2 non-marketers handling execution
Task: Write a 90-day marketing plan with weekly action items and key metrics to track

Example prompt:

I run an early-stage B2B SaaS startup offering a project management tool with 50 paying customers. I want to increase trial signups by 30% over 90 days. My total marketing budget is $5,000 and I have a team of 2 non-marketers. Identify the 3 best acquisition channels, outline content topics for each, suggest how to allocate the budget, and write a 90-day plan with weekly action items and metrics to track progress.

Example: Content Audit

Before (weak prompt):

Audit my blog content

After (structured prompt):

Context: B2B software blog with 80 published posts, mostly top-of-funnel content; organic traffic has stagnated for 6 months
Objective: Identify which posts to update, consolidate, or remove to improve overall SEO performance
Actions: Categorize posts by traffic potential, flag outdated content, identify cannibalization issues
Scenario: I have access to Google Analytics and Search Console data; team can update 4 posts per month
Task: Produce a prioritized audit spreadsheet structure with recommended action per post and rationale

Example prompt:

I manage a B2B software blog with 80 posts, primarily top-of-funnel content, and organic traffic has been flat for 6 months. Using standard SEO principles, help me categorize posts by traffic potential, flag outdated content, and identify topic cannibalization. Assume I can update 4 posts per month. Provide a prioritized audit spreadsheet structure with a recommended action (update, consolidate, or remove) and a one-line rationale for each category.

How to Write a COAST Prompt — Step by Step

Set the Context. Provide background information — who you are, what the project is, and any relevant history the AI needs to know.
Define the Objective. State the primary goal you want to achieve in one clear sentence.
List the Actions. Specify the concrete steps or sub-tasks the AI should perform to accomplish the objective.
Describe the Scenario. Provide situational constraints — budget, team size, timeline, technical limitations, or target audience.
Specify the Task. State the exact deliverable you expect — a plan, a document, a structured list, or a specific output format.

Frequently Asked Questions

What does COAST stand for in prompt engineering?

COAST stands for Context, Objective, Actions, Scenario, Task. It is a five-part prompt framework designed for complex tasks where missing background information would result in a generic or unhelpful AI response.

When should I use COAST instead of TAG?

Use COAST when the AI needs full situational context to produce a useful response — such as business strategy, marketing plans, or research tasks. Use TAG for simple, direct requests that do not require background context.

Is COAST good for business strategy prompts?

Yes, COAST is especially effective for business strategy, marketing planning, and research tasks. The Context and Scenario components ensure the AI understands the environment and constraints before generating recommendations.

Try the Prompt Generator →

Also see: All AI Prompt Frameworks · AI Prompt Optimizer