Fix Skill
Root cause analysis and surgical bug fixes.
When to Activate
This skill is relevant when:
- •Bug reports need investigation
- •Errors need diagnosis and fixing
- •Stack traces need analysis
- •Regression tests needed
- •Production issues require fixes
- •Root cause analysis required
Core Principles
Root Cause Obsessed
- •Don't just patch the symptom
- •Find the underlying disease
- •Understand why it broke
- •Fix the actual problem
- •Prevent future occurrences
Log Whisperer
- •Read stack traces carefully
- •See patterns in error logs
- •Trace execution paths
- •Use logging strategically
- •Follow the error chain
Test-Driven Fixes
- •Bug isn't fixed until test proves it
- •Write failing test first
- •Fix makes test pass
- •Regression test prevents recurrence
- •Green tests confirm fix
Defensive Coding
- •Assume everything will fail
- •Assert early, assert often
- •Validate inputs thoroughly
- •Handle edge cases
- •Add safety checks
Quick Checks
For bug fixes, verify:
- • Bug reproduction case created
- • Failing test demonstrates bug
- • Stack trace or error message analyzed
- • Execution path traced
- • Root cause identified
- • Hypothesis formulated
- • Hypothesis validated against code
- • Fix planned and documented
- • Code changes applied
- • Reproduction test now passes
- • Related tests still pass
- • No side effects introduced
- • Regression test added
- • Safety checks added if needed
- • Fix is clean, no technical debt
Diagnostic Process
Reproduce
- •Get stack trace or error message
- •Create failing test case
- •Document exact reproduction steps
- •Verify the failure (red state)
Diagnose
- •Trace execution path
- •Formulate hypothesis
- •Validate hypothesis
- •Identify root cause
Fix Strategy
- •Document root cause
- •Plan the fix
- •Define verification method
- •Consider side effects
Verify & Protect
- •Test passes (green state)
- •Run regression checks
- •Add assertions
- •Add type checks
- •Prevent recurrence
Fix Documentation
Root Cause
What exactly went wrong and why
The Fix
What code changes were made
Prevention
How we stopped it from recurring
Verification
How we proved it's fixed