# Vc Debug

Debug systematically with root-cause analysis before fixes.

- Repository: https://github.com/withkynam/vibecode-pro-max-kit (1164 stars)
- Category: Testing
- License: MIT
- Last updated: 2026-06-21
- Runs scripts: yes, review before use

## Install

Claude Code: `npx skills add withkynam/vibecode-pro-max-kit --skill vc-debug -g -a claude-code -y`
Codex: `npx skills add withkynam/vibecode-pro-max-kit --skill vc-debug -g -a codex -y`
Cursor: `npx skills add withkynam/vibecode-pro-max-kit --skill vc-debug -g -a cursor -y`
Gemini CLI: `npx skills add withkynam/vibecode-pro-max-kit --skill vc-debug -g -a gemini-cli -y`

## Description

Debug systematically with root-cause analysis before fixes. Use for bugs, test failures, unexpected behavior, performance issues, CI failures, or system investigation.

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

# Debugging & System Investigation

> **Output style:** Follow `process/development-protocols/communication-standards.md`, answer-first, plain language, no unexplained jargon, TL;DR on long responses.

Comprehensive framework combining systematic debugging, root cause tracing, defense-in-depth validation, verification protocols, and system-level investigation (logs, CI/CD, databases, performance).

## Core Principle

**NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST**

Random fixes waste time and create new bugs. Find root cause, fix at source, validate at every layer, verify before claiming success.

## When to Use

**Code-level:** Test failures, bugs, unexpected behavior, build failures, integration problems
**System-level:** Server errors, CI/CD pipeline failures, performance degradation, database issues, log analysis
**Always:** Before claiming work complete

## Techniques

### 1. Systematic Debugging (`references/systematic-debugging.md`)

Four-phase framework: Root Cause Investigation → Pattern Analysis → Hypothesis Testing → Implementation. Complete each phase before proceeding. No fixes without Phase 1.

**Load when:** Any bug/issue requiring investigation and fix

### 2. Root Cause Tracing (`references/root-cause-tracing.md`)

Trace bugs backward through call stack to find original trigger. Fix at source, not symptom. Includes `scripts/find-polluter.sh` for bisecting test pollution.

**Load when:** Error deep in call stack, unclear where invalid data originated

### 3. Defense-in-Depth (`references/defense-in-depth.md`)

Validate at every layer: Entry validation → Business logic → Environment guards → Debug instrumentation

**Load when:** After finding root cause, need comprehensive validation

### 4. Verification (`references/verification.md`)

**Iron law:** NO COMPLETION CLAIMS WITHOUT FRESH VERIFICATION EVIDENCE. Run command. Read output. Then claim result.

**Load when:** About to claim work complete, fixed, or passing

The rest: https://github.com/withkynam/vibecode-pro-max-kit/blob/HEAD/.claude/skills/vc-debug/SKILL.md