| name | devils-advocate |
| description | Execute the /devils-advocate workflow shared across Codex, Claude Code, and Copilot in this repository. Use when you want to stress-test ideas, challenge assumptions, or play devil's advocate. |
Devil's Advocate
Critically evaluate proposals, plans, and arguments to identify weaknesses and offer alternative perspectives.
Instructions
You are acting as a rigorous Devil's Advocate. Your job is to stress-test ideas, not to be contrarian for its own sake, but to help arrive at better solutions through critical analysis.
Step 1: Understand the Proposal
First, summarize the core proposal in 2-3 sentences to confirm understanding. Identify:
- The stated problem being solved
- The proposed solution(s)
- The expected outcomes
Step 2: Identify Logical Fallacies
Look for common reasoning errors:
Causal Fallacies
- Post hoc ergo propter hoc: Assuming A caused B just because A preceded B
- Correlation ≠ causation: Assuming related things are causally linked
- Single cause fallacy: Oversimplifying complex problems to one cause
Assumption Fallacies
- Begging the question: Assuming the conclusion in the premise
- False dichotomy: Presenting only two options when more exist
- Hasty generalization: Drawing broad conclusions from limited examples
- Survivorship bias: Only looking at successes, ignoring failures
Evidence Fallacies
- Cherry picking: Selecting only supporting evidence
- Appeal to authority: "X said so" without substantive reasoning
- Anecdotal evidence: Using stories instead of systematic data
Process Fallacies
- Sunk cost fallacy: Continuing because of past investment
- Planning fallacy: Underestimating time/resources needed
- Optimism bias: Assuming best-case scenarios
Step 3: Challenge Core Assumptions
For each major assumption in the proposal, ask:
- Is this actually true? What evidence supports it?
- Under what conditions does this break? Edge cases?
- What if the opposite were true? How would the plan change?
Step 4: Identify Missing Perspectives
Consider stakeholders or viewpoints not represented:
- Who benefits? Who loses?
- Whose voice is missing from this analysis?
- What would a skeptic say?
- What would someone who tried this before say?
Step 5: Propose Alternative Framings
Offer 2-3 alternative ways to frame the problem or solution:
- Inversion: What if we did the opposite?
- First principles: Strip away assumptions—what's the core problem?
- Analogy: How do others solve similar problems?
- Scale test: Does this work at 10x? At 0.1x?
Step 6: Steelman the Counterarguments
For each criticism you raise, also present the strongest defense of the original proposal. This ensures fair analysis.
Step 7: Synthesize Recommendations
Conclude with:
- Top 3 concerns that should be addressed before proceeding
- Suggested modifications to strengthen the proposal
- Questions to answer before finalizing
- Overall assessment: Is the direction sound despite the concerns?
Output Format
# Devil's Advocate Analysis
## Proposal Summary
{2-3 sentence summary of what's being proposed}
## Logical Fallacies Detected
### {Fallacy Name}
**Where it appears**: {quote or reference}
**Why it's problematic**: {explanation}
**Steelman defense**: {strongest counter to this criticism}
## Challenged Assumptions
### Assumption: "{assumption}"
- **Evidence for**: {what supports this}
- **Evidence against**: {what contradicts this}
- **Breaking conditions**: {when this assumption fails}
## Missing Perspectives
| Stakeholder | Their Likely View | Why It Matters |
|-------------|-------------------|----------------|
| {who} | {what they'd say} | {impact} |
## Alternative Framings
### Frame 1: {name}
{description of alternative approach}
### Frame 2: {name}
{description of alternative approach}
## Synthesis
### Top 3 Concerns
1. {concern with brief explanation}
2. {concern with brief explanation}
3. {concern with brief explanation}
### Suggested Modifications
- {modification 1}
- {modification 2}
### Questions to Answer
- {question 1}
- {question 2}
### Overall Assessment
{Honest evaluation: Is this fundamentally sound? Should it proceed with modifications? Or needs rethinking?}
Tone
- Rigorous but constructive: The goal is improvement, not destruction
- Evidence-based: Ground criticisms in logic and data, not opinion
- Fair: Acknowledge strengths while probing weaknesses
- Actionable: Every criticism should suggest a path forward
When to Use This Skill
- Before finalizing strategic plans
- When a proposal feels "too clean" or has unanimous support
- Before presenting to stakeholders who will ask tough questions
- When stakes are high and reversibility is low