Agent skill · software engineering · aiskillstore
systematic-debugging
Four-phase debugging methodology with root cause analysis. Use when investigating bugs, fixing test failures, or troubleshooting unexpected behavior. Emphasizes NO FIXES WITHOUT ROOT CAUSE FIRST.
Why this skill is useful
Provides a structured debugging methodology that helps identify root causes and avoid symptom-focused fixes, which the AI may not reliably generate on its own.
What it needs
About 3k tokens when loaded. Last updated 2026-08-07. 405 stars on the source repository.
What this skill does
Systematic Debugging Core Principle NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST. Never apply symptom-focused patches that mask underlying problems. Understand WHY something fails before attempting to fix it. The Four-Phase Framework Phase 1: Root Cause Investigation Before touching any code: 1. Read error messages thoroughly - Every word matters 2. Reproduce the issue consistently - If you can't reproduce it, you can't verify a fix 3. Examine recent changes - What changed before this started failing? 4. Gather diagnostic evidence - Logs, stack traces, state dumps 5. Trace data flow - Follow the call chain to find where bad values originate Root Cause Tracing Technique: Key principle: Never fix problems solely where errors appear—always trace to the original trigger. Phase 2: Pattern Analysis 1. Locate working examples - Find similar code that works correctly 2. Compare implementations completely - Don't just skim 3. Identify differences - What's different between working and broken? 4. Understand dependencies - What does this code depend on? Phase 3: Hypothesis and Testing Apply the scientific method: 1. Formulate ONE clear hypothesis - "The error occurs because X" 2. Design minimal test - Change ONE variable at a time 3. Predict the outcome - What should happen if hypothesis is correct? 4. Run the test - Execute and observe 5. Verify results - Did it behave as predicted? 6. Iterate or proceed - Refine hypothesis if wrong, implement if right Phase 4: Implementation 1. Create failing test case - Captures the bug behavior 2. Implement single fix - Address root cause, not symptoms 3. Verify test passes - Confirms fix works 4. Run full test suite - Ensure no regressions 5. If fix fails, STOP - Re-evaluate hypothesis Critical rule: If THREE or more fixes fail consecutively, STOP. This signals architectural problems requiring discussion, not more patches. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills aiskillstore/systematic-debugging--b22b9a