Analyze A/B test results with statistical significance, sample size validation, confidence intervals, and ship/extend/stop recommendations. Use when evaluating experiment results, checking if a test reached significance, interpreting split test data, or deciding whether to ship a variant.
pre-mortem
pre-mortem is an open-source testing skill for Claude Code and compatible agents, published by phuryn. Its author describes it as: “Run a pre-mortem risk analysis on a PRD or launch plan. Categorizes risks as Tigers (real problems), Paper Tigers (overblown concerns), and Elephants (unspoken worries), then classifies as launch-blocking, fast-follow…”. The project has 25k stars on GitHub and is available under the MIT license. Add it to your setup with `/plugin marketplace add phuryn/pm-skills`.
What pre-mortem does
You are a veteran product manager conducting a pre-mortem analysis on $ARGUMENTS. This skill imagines launch failure and works backward to identify real risks, distinguish them from perceived worries, and create action plans to mitigate launch-blocking issues.
Installation
Add pre-mortem to your agent with:
/plugin marketplace add phuryn/pm-skillsAlways review a skill's source before installing it. This command comes from the skill's public repository; the linked repo is the source of truth for exact setup steps.
What's inside
The SKILL.md for pre-mortem is organised into these sections:
- Purpose
- Context
- Instructions
- Notes
- Further Reading
When to use it
Reach for pre-mortem when you want testing help from your agent without writing the same instructions every session. Load the skill and the agent picks it up automatically for relevant tasks.
Strengths
- Clear MIT license — safe to read and adapt
- Ships in phuryn/pm-skills, an established project with 25,392 GitHub stars
- Actively maintained (recent commits)
Topics
Frequently asked questions
- What does pre-mortem do?
- Run a pre-mortem risk analysis on a PRD or launch plan. Categorizes risks as Tigers (real problems), Paper Tigers (overblown concerns), and Elephants (unspoken worries), then classifies as launch-blocking, fast-follow, or track. Use when preparing for launch, stress-testing a product plan, or identifying what could go wrong.
- How do I install pre-mortem?
- Run /plugin marketplace add phuryn/pm-skills in your agent, then reload your skills. Review the source at https://github.com/phuryn/pm-skills before installing.
- Is pre-mortem free to use?
- Yes. pre-mortem is free and open source under the MIT license, so you can read, run, and adapt it within that license's terms.
- Where does pre-mortem come from?
- pre-mortem ships inside phuryn/pm-skills, a repository that contains 41 catalogued skills in total. The repository's 25,392 GitHub stars apply to that whole collection, not to this skill on its own.
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