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Pre-Mortem Plan Analysis

Free

Identify weaknesses in your plans before execution.

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Free · Opens the source repo

What Pre-Mortem Plan Analysis does

The Pre-Mortem Plan Analysis skill is designed to help teams critically evaluate their plans by identifying potential weaknesses before they are put into action. By employing a systematic approach, this skill encourages users to imagine a scenario where their plan has failed and to work backwards to uncover the underlying assumptions and dependencies that could lead to such an outcome. This proactive analysis is crucial for anyone involved in project management, product development, or strategic planning, as it helps surface risks and vulnerabilities that may not be immediately apparent.

The skill operates through a structured framework that includes extracting core assumptions, rating their confidence and impact, mapping vulnerabilities, analyzing dependency chains, and assessing reversibility. Each step is aimed at fostering a deeper understanding of the plan's potential pitfalls, enabling teams to make informed decisions about resource allocation and risk management. This method is particularly useful when there is pressure to move quickly or when feedback has been overwhelmingly positive, as it prompts a necessary critical examination of the plan.

Ideal for project managers, product owners, and business strategists, the Pre-Mortem Plan Analysis skill is a valuable tool for anyone looking to ensure their plans are robust and resilient. By integrating this skill into the planning process, teams can enhance their ability to anticipate challenges and adapt their strategies accordingly, ultimately increasing the likelihood of successful outcomes.

This skill is not a replacement for traditional planning methods but rather a complementary approach that emphasizes the importance of critical thinking and risk assessment in the planning process. It is particularly beneficial in high-stakes environments where the cost of failure is significant, and thorough preparation is essential for success.

When to use it

Use this skill before committing significant resources to a plan or when preparing to present to stakeholders.

When not to use it

This skill may not be suitable for simple or low-stakes plans where the cost of failure is minimal.

What you can build with it

Evaluating a New Product Launch

Before launching a new product, use the skill to identify assumptions about market demand and execution capabilities.

Preparing for Investor Presentations

Run a pre-mortem analysis to anticipate questions and concerns from investors regarding your business plan.

Assessing a Hiring Strategy

Use this skill to evaluate the dependencies and assumptions in your hiring plan, ensuring you are prepared for potential challenges.

How to install Pre-Mortem Plan Analysis

View source

1. Install with the skills CLI

npx skills add alirezarezvani/claude-skills/challenge --agent claude-code

2. Or install it manually

Download the skill folder and drop it into ~/.claude/skills/ for all projects, or .claude/skills/ to scope it to one repo. Restart Claude Code so it picks up the new skill.

Anthropic's agentic coding CLI, and the reference implementation of Agent Skills. Drop a skill folder into ~/.claude/skills and Claude Code loads it automatically whenever a task matches the skill's description. Claude Code docs

Inside SKILL.md

Written by alirezarezvani

/em:challenge — Pre-Mortem Plan Analysis

Command: /em:challenge <plan>

Systematically finds weaknesses in any plan before reality does. Not to kill the plan — to make it survive contact with reality.


The Core Idea

Most plans fail for predictable reasons. Not bad luck — bad assumptions. Overestimated demand. Underestimated complexity. Dependencies nobody questioned. Timing that made sense in a spreadsheet but not in the real world.

The pre-mortem technique: imagine it's 12 months from now and this plan failed spectacularly. Now work backwards. Why?

That's not pessimism. It's how you build something that doesn't collapse.


When to Run a Challenge

  • Before committing significant resources to a plan
  • Before presenting to the board or investors
  • When you notice you're only hearing positive feedback about the plan
  • When the plan requires multiple external dependencies to align
  • When there's pressure to move fast and "figure it out later"
  • When you feel excited about the plan (excitement is a signal to scrutinize harder)

The Challenge Framework

Step 1: Extract Core Assumptions

Before you can test a plan, you need to surface everything it assumes to be true.

For each section of the plan, ask:

  • What has to be true for this to work?
  • What are we assuming about customer behavior?
  • What are we assuming about competitor response?
  • What are we assuming about our own execution capability?
  • What external factors does this depend on?

Common assumption categories:

  • Market assumptions — size, growth rate, customer willingness to pay, buying cycle
  • Execution assumptions — team capacity, velocity, no major hires needed
  • Customer assumptions — they have the problem, they know they have it, they'll pay to solve it
  • Competitive assumptions — incumbents won't respond, no new entrant, moat holds
  • Financial assumptions — burn rate, revenue timing, CAC, LTV ratios
  • Dependency assumptions — partner will deliver, API won't change, regulations won't shift

Step 2: Rate Each Assumption

For every assumption extracted, rate it on two dimensions:

Confidence level (how sure are you this is true):

  • High — verified with data, customer conversations, market research
  • Medium — directionally right but not validated
  • Low — plausible but untested
  • Unknown — we simply don't know

Impact if wrong (what happens if this assumption fails):

  • Critical — plan fails entirely
  • High — major delay or cost overrun
  • Medium — significant rework required
  • Low — manageable adjustment

Step 3: Map Vulnerabilities

The matrix of Low/Unknown confidence × Critical/High impact = your highest-risk assumptions.

Vulnerability = Low confidence + High impact

These are not problems to ignore. They're the bets you're making. The question is: are you making them consciously?

Step 4: Find the Dependency Chain

Many plans fail not because any single assumption is wrong, but because multiple assumptions have to be right simultaneously.

Map the chain:

  • Does assumption B depend on assumption A being true first?
  • If the first thing goes wrong, how many downstream things break?
  • What's the critical path? What has zero slack?

Step 5: Test the Reversibility

For each critical vulnerability: if this assumption turns out to be wrong at month 3, what do you do?

  • Can you pivot?
  • Can you cut scope?
  • Is money already spent?
  • Are commitments already made?

The less reversible, the more rigorously you need to validate before committing.


Output Format

Challenge Report: [Plan Name]

CORE ASSUMPTIONS (extracted)
1. [Assumption] — Confidence: [H/M/L/?] — Impact if wrong: [Critical/High/Medium/Low]
2. ...

VULNERABILITY MAP
Critical risks (act before proceeding):
• [#N] [Assumption] — WHY it might be wrong — WHAT breaks if it is

High risks (validate before scaling):
• ...

DEPENDENCY CHAIN
[Assumption A] → depends on → [Assumption B] → which enables → [Assumption C]
Weakest link: [X] — if this breaks, [Y] and [Z] also fail

REVERSIBILITY ASSESSMENT
• Reversible bets: [list]
• Irreversible commitments: [list — treat with extreme care]

KILL SWITCHES
What would have to be true at [30/60/90 days] to continue vs. kill/pivot?
• Continue if: ...
• Kill/pivot if: ...

HARDENING ACTIONS
1. [Specific validation to do before proceeding]
2. [Alternative approach to consider]
3. [Contingency to build into the plan]

Challenge Patterns by Plan Type

Product Roadmap

  • Are we building what customers will pay for, or what they said they wanted?
  • Does the velocity estimate account for real team capacity (not theoretical)?
  • What happens if the anchor feature takes 3× longer than estimated?
  • Who owns decisions when requirements conflict?

Go-to-Market Plan

  • What's the actual ICP conversion rate, not the hoped-for one?
  • How many touches to close, and do you have the sales capacity for that?
  • What happens if the first 10 deals take 3 months instead of 1?
  • Is "land and expand" a real motion or a hope?

Hiring Plan

  • What happens if the key hire takes 4 months to find, not 6 weeks?
  • Is the plan dependent on retaining specific people who might leave?
  • Does the plan account for ramp time (usually 3–6 months before full productivity)?
  • What's the burn impact if headcount leads revenue by 6 months?

Fundraising Plan

  • What's your fallback if the lead investor passes?
  • Have you modeled the timeline if it takes 6 months, not 3?
  • What's your runway at current burn if the round closes at the low end?
  • What assumptions break if you raise 50% of the target amount?

The Hardest Questions

These are the ones people skip:

  • "What's the bear case, not the base case?"
  • "If this exact plan was run by a team we don't trust, would it work?"
  • "What are we not saying out loud because it's uncomfortable?"
  • "Who has incentives to make this plan sound better than it is?"
  • "What would an enemy of this plan attack first?"

Deliverable

The output of /em:challenge is not permission to stop. It's a vulnerability map. Now you can make conscious decisions: validate the risky assumptions, hedge the critical ones, or accept the bets you're making knowingly.

Unknown risks are dangerous. Known risks are manageable.

Frequently asked questions about Pre-Mortem Plan Analysis

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