ck-debug

# Debugging & System Investigation 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 ### 5. Investigation Methodology (`references/investigation-methodology.md`) Five-step structured investigation for system-level issues: Initial Assessment → Data Collection → Analysis → Root Cause ID → Solution Development **Load when:** Server incidents, system behavior analysis, multi-component failures ### 6. Log & CI/CD Analysis (`references/log-and-ci-analysis.md`) Collect and analyze logs from servers, CI/CD pipelines (GitHub Actions), application layers. Tools: `gh` CLI, structured log queries, correlation across sources. **Load when:** CI/CD pipeline failures, server errors, deployment issues ### 7. Performance Diagnostics (`references/performance-diagnostics.md`) Identify bottlenecks, analyze query performance, develop optimization strategies. Covers database queries, API response times, resource utilization. **Load when:** Performance degradation, slow queries, high latency, resource exhaustion ### 8. Reporting Standards (`references/reporting-standards.md`) Structured diagnostic reports: Executive Summary → Technical Analysis → Recommendations → Evidence **Load when:** Need to produce investigation report or diagnostic summary ### 9. Task Management (`references/task-management-debugging.md`) Track investigation pipelines via Claude Native Tasks (TaskCreate, TaskUpdate, TaskList). Hydration pattern for multi-step investigations with dependency chains and parallel evidence collection. **Fallback:** Task tools are CLI-only — if unavailable (VSCode extension), use `TodoWrite` for tracking. Debug workflow remains fully functional. **Load when:** Multi-component investigation (3+ steps), parallel log collection, coordinating debugger subagents ### 10. Frontend Verification (`references/frontend-verification.md`) Visual verification of frontend implementations via Chrome MCP (Claude Chrome Extension) or `ck:chrome-devtools` skill fallback. Detect if frontend-related → check Chrome MCP availability → screenshot + console error check → report. Skip if not frontend. **Load when:** Implementation touches frontend files (tsx/jsx/vue/svelte/html/css), UI bugs, visual regressions ## Quick Reference ``` Code bug → systematic-debugging.md (Phase 1-4) Deep in stack → root-cause-tracing.md (trace backward) Found cause → defense-in-depth.md (add layers) Claiming done → verification.md (verify first) System issue → investigation-methodology.md (5 steps) CI/CD failure → log-and-ci-analysis.md Slow system → performance-diagnostics.md Need report → reporting-standards.md Frontend fix → frontend-verification.md (Chrome/devtools) ``` ## Tools Integration - **Database:** `psql` for PostgreSQL queries and diagnostics - **CI/CD:** `gh` CLI for GitHub Actions logs and pipeline debugging - **Codebase:** `ck:docs-seeker` skill for package/plugin docs; `ck:repomix` skill for codebase summary - **Scouting:** `/ck:scout` or `/ck:scout ext` for finding relevant files - **Frontend:** Chrome browser or `ck:chrome-devtools` skill for visual verification (screenshots, console, network) - **Skills:** Activate `ck:problem-solving` skill when stuck on complex issues ## Red Flags Stop and follow process if thinking: - "Quick fix for now, investigate later" - "Just try changing X and see if it works" - "It's probably X, let me fix that" - "Should work now" / "Seems fixed" - "Tests pass, we're done" **All mean:** Return to systematic process.