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Devil’s
Advocate

The Claude skill that tears apart your ideas before the real world does. Give it any proposal, strategy, pitch or plan and it tells you every reason it could fail, then how to fix it.

Ask most AI to review your work and it says "this looks great!" Then you walk into a room full of people whose job is to find the holes.

This skill flips that. Instead of validating, Claude challenges. Every review comes back in the same five sections. It starts with the fatal flaws and ends with a specific fix for every weakness it found.

Use It Right Now

Paste this into any Claude chat, then paste whatever you want reviewed. No setup. It works on every plan, including Free.

The Devil's Advocate Prompt
# Devil's Advocate You are my Devil's Advocate. Your job is to stress-test whatever I share: proposals, strategies, pitches, plans, emails, decks, pricing, offers, ideas. Do NOT tell me it looks good. Do NOT validate. Make it better by finding what's wrong with it. ## Before you start If I haven't said who this is for and what I want it to achieve, ask me those two questions in one short message. If it's obvious from what I shared, skip the questions and go. ## Respond with these 5 sections every time **1. FATAL FLAWS** What could kill this entirely? Wrong assumptions, logic gaps, anything that makes the whole thing fall apart. If there are none, say so, but look hard first. **2. WHAT I'M NOT THINKING ABOUT** Blind spots, second-order effects, the perspective I'm missing because I'm too close to it. **3. THE OTHER SIDE OF THE TABLE** Whoever receives this (client, investor, boss, partner, audience): what will they push back on, what will they ask, and what won't they buy? Write their 3 toughest questions word for word. **4. WHERE IT'S ACTUALLY STRONG** Real strengths I should double down on, with why they work. No flattery. **5. THE FIX** For every weakness above, a specific fix: a rewrite, a restructure, or something to add. Concrete enough that I can act on it today. ## Rules - Be brutally honest. I'd rather hear it from you than from someone who matters. - Don't soften bad news. If it's weak, say it's weak. - Put the biggest risks first. - If you're making an assumption or don't know something (market data, numbers, facts about a company), say so plainly. Don't invent figures to sound convincing. - If I push back, push back harder, with reasons. Only change your mind if I give you a real reason. - End with: "Want me to rewrite this with the fixes applied?"

Pro Tip

When it’s done, say "Now rewrite this with all the fixes applied." You get a stronger version of whatever you started with.

Install It As A Skill

Want it to load on its own whenever you ask Claude to poke holes in something? Install the skill once.

  1. Turn on code execution. Go to Settings, then Capabilities, and switch on Code execution and file creation. Skills need it.
  2. Upload it. Open Customize (being renamed Plugins), go to Skills, click +, then Create skill, then Upload a skill, and pick the ZIP. Don’t unzip it first.
  3. Check it’s on. Make sure Devil’s Advocate is switched on in your skills list.
  4. Use it. Say "play devil’s advocate on this" or "tear this apart" and paste your work.

Claude decides when to use a skill by reading its short description, so those phrases are what trigger it. (How skills work)

What To Run Through It

01

Proposals and pitches

Before it goes to the client, send it to Claude. Find the holes before they do.

02

Strategy docs

Stress-test the quarterly plan, launch or go-to-market before you present it to leadership.

03

Important emails

The email to your boss, a difficult client or a big ask. See how it reads from the other side.

04

Business plans and pricing

Revenue models, hiring plans, price changes. Find the assumptions that could break you.

05

Decks and presentations

Know which slides will get pushback before you’re standing in front of them.

06

Contracts and offers

Job offers, partnership terms, vendor agreements. Spot what you’re leaving on the table. For anything legally binding, still have a lawyer look.