The Anatomy of a Great Prompt

Yesterday we talked about the Role + Context + Task + Format framework. Today I want to zoom in on the first piece, because it's the single highest-leverage thing you can do.

It's this: tell the AI who to be.

That's it. One sentence at the top of your prompt. And it changes everything.

The persona trick

Compare these two:

Without a role: "Review this quarterly budget and give me feedback."

With a role: "You are a CFO with 20 years of experience in SaaS companies. Review this quarterly budget and give me feedback. Focus on cash flow risks and areas where we're overspending relative to growth stage."

The first gives you generic bullet points that sound like a finance textbook. The second gives you the kind of sharp, experienced feedback you'd actually pay a consultant for.

Why does this work? Remember from Week 1: AI is pattern matching across everything it's been trained on. When you say "act as a CFO," you're essentially telling it to pull from patterns associated with how CFOs think, what they prioritize, and how they communicate. You're narrowing the search space from "everything" to "this specific type of expertise."

It's like the difference between asking "someone" for advice versus asking your smartest friend who happens to work in that exact field.

Five roles that work for almost anything

You don't need to get creative here. These five cover probably 80% of what a business professional needs:

1. "You are a senior strategy consultant." Use for: analyzing decisions, evaluating plans, weighing tradeoffs. You'll get structured thinking and frameworks.

1. "You are an expert copywriter." Use for: emails, landing pages, presentations, any writing where persuasion matters. The tone shifts immediately.

1. "You are a skeptical board member." Use for: stress-testing ideas, finding holes in your plan, preparing for tough questions. This one is gold for presentation prep.

1. "You are a data analyst." Use for: making sense of numbers, finding patterns in spreadsheets, creating charts or summaries from raw data.

1. "You are my executive coach." Use for: career decisions, managing up, navigating office politics, thinking through tough conversations. Surprisingly good at this.

When personas shine

The persona trick is most powerful in a few specific situations:

Getting feedback. Instead of "what do you think of this email?" try "You're the recipient of this email. You're a busy VP who gets 200 emails a day. Would you read past the first line? Be honest."

Brainstorming. "You're the head of growth at a B2B startup. Give me 10 unconventional ways to generate leads without paid ads."

Editing your own work. "You're a ruthless editor at The Economist. Cut this 800-word memo down to 400 words without losing any key points."

See the pattern? You're not just asking for help. You're telling the AI exactly what lens to look through.

The combining trick

Here's where it gets really useful. You can stack roles.

"First, act as a marketing director and write me a launch plan for this product. Then, switch roles: act as the CFO and poke holes in the budget. Finally, act as the customer and tell me honestly if you'd care about this."

Three perspectives. One conversation. That's the kind of analysis that would take a week of meetings to get from real people.

One thing to try right now

Next time you open ChatGPT or Claude, before you type your actual question, start with: "You are a [specific expert] with [specific experience]."

Make it specific. "A marketing consultant" is fine. "A marketing consultant who specializes in B2B SaaS companies with $10-50M revenue" is better. The more specific the role, the more specific the output.

One sentence of context ("Act as...") can transform the quality of every response you get from AI.