What is defense-in-depth in the context of debugging?

Defense-in-depth involves adding validation at every layer of the call stack once a bug is found, ensuring that similar issues are caught immediately in the future rather than propagating through the system.

What is the core principle of Root Cause Tracing?

The core principle is to never fix just the symptom where an error appears; instead, you must trace backward through the call chain until you find the original trigger and fix it at the source.

When is the best time to use the Root Cause Tracing skill?

Use it when an error occurs deep in execution with a long call chain, or when it is unclear where the invalid data causing a crash actually originated.

How does this skill handle test pollution?

It provides methodology and bisection scripts that run tests one-by-one to identify which specific test is leaking state or 'polluting' the environment for subsequent tests.

Does this work for both frontend and backend code?

While the provided examples focus on backend environments like Node.js and Python, the systematic tracing and instrumentation principles apply to any complex software execution stack.

Root Cause Tracing

Name: Root Cause Tracing
Author: carlopezzuto

bycarlopezzuto

0•

Security & Testing

Systematically identifies the original source of software bugs by tracing execution flow backward through the call stack to ensure permanent fixes at the trigger point.

Root Cause Tracing is a specialized skill for Claude Code designed to help developers solve complex bugs that manifest deep within an execution chain. Instead of applying 'band-aid' fixes to symptoms, this skill provides a structured methodology for traversing the call stack to find the initial trigger of invalid data or incorrect state. It emphasizes the use of instrumentation, stack trace analysis, and defense-in-depth validation patterns to ensure bugs are eliminated at their source. It also includes specific strategies for identifying test pollution in large suites using bisection techniques for both TypeScript and Python environments.

Key Features

01Structured heuristics for differentiating between immediate symptoms and root causes

02Defense-in-depth implementation patterns for multi-layered validation

03Systematic backward call stack traversal to identify original bug triggers

04Instrumentation guidance using manual stack traces and environment-aware logging

05Automated test pollution isolation using bisection scripts for JS/TS and Python

060 GitHub stars

Use Cases

01Identifying specific tests causing environmental pollution in large, flaky test suites

02Debugging silent failures where invalid data originates far from the eventual crash point

03Implementing robust validation layers to prevent regressions in complex backend services

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add carlopezzuto/agents root-cause-tracing

For use in Claude.ai and ChatGPT

Download Skill