Root Cause Tracing

When bugs appear five levels deep in your call stack, your instinct is to patch where the error shows up. This skill forces you to trace backward through the entire chain until you find the actual source. It walks through adding stack trace instrumentation with console.error (not logger, which tests suppress), running bisection scripts to find which test pollutes state, and systematically moving up the call chain. The real value is the discipline: never fix the symptom, always fix the trigger, then add validation at every layer you traced through. Includes a concrete example of tracking an empty string through five function calls to find it was a test accessing a fixture before beforeEach ran.

skills.sh installs: 1.3K
GitHub stars: 1.8K
last updated: Aug 21, 2026

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Install

$ npx -y skills add neolabhq/context-engineering-kit --skill root-cause-tracing --agent claude-code

Installs into .claude/skills of the current project.

Files

Root Cause Tracing

Overview

Bugs often manifest deep in the call stack (git init in wrong directory, file created in wrong location, database opened with wrong path). Your instinct is to fix where the error appears, but that's treating a symptom.

Core principle: Trace backward through the call chain until you find the original trigger, then fix at the source.

When to Use

digraph when_to_use {
    "Bug appears deep in stack?" [shape=diamond];
    "Can trace backwards?" [shape=diamond];
    "Fix at symptom point" [shape=box];
    "Trace to original trigger" [shape=box];
    "BETTER: Also add defense-in-depth" [shape=box];

    "Bug appears deep in stack?" -> "Can trace backwards?" [label="yes"];
    "Can trace backwards?" -> "Trace to original trigger" [label="yes"];
    "Can trace backwards?" -> "Fix at symptom point" [label="no - dead end"];
    "Trace to original trigger" -> "BETTER: Also add defense-in-depth";
}

Use when: