Debug
Systematic root cause investigation using scientific method.
Purpose
The Debug skill investigates bugs using systematic root cause analysis. No guessing — it finds the cause before attempting fixes, following a four-phase scientific method.
Usage
/development:debug <issue>Example:
/development:debug login returns 403 for valid usersWhat It Does
Phase 1: Investigation
- Reads error messages and stack traces carefully
- Reproduces the issue reliably
- Checks recent changes (git log, git diff)
Phase 2: Analysis
- Traces the data flow backward to the source
- Compares with similar working code
Phase 3: Hypothesis
- Forms a single, specific hypothesis
- Tests with the smallest possible change
Phase 4: Fix
- Writes a failing test reproducing the bug
- Implements the root cause fix
- Verifies all tests pass
Output
No sequential artifact — fixes are committed directly. Presents findings to the user: root cause, fix applied, commit hash, and related issues discovered.