nw-five-whys-methodology
Toyota 5 Whys methodology with multi-causal branching, evidence requirements, and validation techniques
npx skills add majiayu000/claude-skill-registry --skill nw-five-whys-methodology --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Five Whys Methodology ## Philosophical Foundation Taiichi Ohno: "By repeating why five times, the nature of the problem as well as its solution becomes clear." Core tenets: scientific evidence-based investigation | address fundamental causes not symptoms | solve to prevent recurrence | use findings for Kaizen ## Multi-Causal Investigation Complex problems have multiple root causes. Investigate comprehensively: - **Parallel**: investigate all symptoms/conditions simultaneously - **Branch**: follow each cause through all five WHY levels - **Cross-cause**: ensure multiple causes don't contradict - **Comprehensive**: address all root causes, not just primary ## WHY Level Definitions ### WHY 1: Symptom Investigation What is immediately observable? Investigate all symptoms. Each branch continues independently. Document verifiable evidence per symptom. ``` WHY 1A: Path not found [Evidence: file exists but wrong context -- Windows vs WSL paths] WHY 1B: Permission denied [Evidence: user context mismatch between host and container] WHY 1C: Timing issues [Evidence: race conditions with file system operations] ``` ### WHY 2: Context Analysis Why does this condition exist? Follow each WHY 1 t
- Philosophical Foundation
- Multi-Causal Investigation
- WHY Level Definitions
- WHY 1: Symptom Investigation
- WHY 2: Context Analysis
- WHY 3: System Analysis
- WHY 4: Design Analysis
- WHY 5: Root Cause Identification
- Validation and Verification
- Evidence Requirements
- Backwards Chain Validation
- Solution Completeness
- Branch Documentation Format
What does the nw-five-whys-methodology skill do?
Toyota 5 Whys methodology with multi-causal branching, evidence requirements, and validation techniques
How do I install it?
Run `npx skills add majiayu000/claude-skill-registry --skill nw-five-whys-methodology --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From majiayu000/claude-skill-registry, a repository with 534 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.