# Thinking Pre Mortem

Before committing to a plan or launch, assume it already failed and reason backward...

- Repository: https://github.com/tjboudreaux/cc-thinking-skills (1690 stars)
- Category: Engineering
- License: MIT
- Last updated: 2026-08-07
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add tjboudreaux/cc-thinking-skills --skill thinking-pre-mortem -g -a claude-code -y`
Codex: `npx skills add tjboudreaux/cc-thinking-skills --skill thinking-pre-mortem -g -a codex -y`
Cursor: `npx skills add tjboudreaux/cc-thinking-skills --skill thinking-pre-mortem -g -a cursor -y`
Gemini CLI: `npx skills add tjboudreaux/cc-thinking-skills --skill thinking-pre-mortem -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add tjboudreaux/cc-thinking-skills`

## Description

Before committing to a plan or launch, assume it already failed and reason backward through concrete causes, convert failure paths into mitigations, gates, and stop checks.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Pre-Mortem Analysis

**Core rule:** Prospective hindsight beats "what could go wrong?" Assume the plan has already failed (past tense), generate concrete failure paths, reverse them into prevention requirements, and bind each top path to a verifiable plan change.

## When to Use

- Before kickoff, major technical commitment, high-risk sprint work, launch, or release.
- After a plan looks solid but before execution, especially when optimism or overconfidence is likely.
- When a decision is costly to reverse and risks are still implicit rather than enforced.

## When NOT to Use

- Work is small, local, and cheaply reversible, skip the ceremony.
- You are mid-incident under time pressure, act now (OODA / scientific method); pre-mortem is pre-execution.
- You would only emit generic risks ("scope creep", "requirements unclear") that do not bind to this plan.
- Risks are already enforced by live gates (CI, canary, rollback, alerts) with no residual unlisted path.
- A mature risk register already covers the same specific failure paths with owners and checks.

## Procedure

The rest: https://github.com/tjboudreaux/cc-thinking-skills/blob/HEAD/skills/thinking-pre-mortem/SKILL.md