Diagnose

A discipline for hard bugs and regressions. Skip phases only when explicitly justified. All questions and findings reported to the user must be in Portuguese (pt-BR).

When exploring the codebase, use the project's domain glossary from .claude/CONTEXT.md to get a clear mental model of the relevant modules, and check docs/architecture/ for decisions in the area you are touching.

Re-validation loop: after every hypothesis, fix, or change, re-run the reproduction and the regression checks before declaring the bug resolved.

When to Use

• User asks or mentions this skill in English (e.g., "use /diagnose", "run diagnose").
• O usuário pede ou menciona esta skill em português (ex.: "use /diagnose", "execute diagnose").

Phase 1 — Build a feedback loop

This is the skill. Everything else is mechanical. If you have a fast, deterministic, agent-runnable pass/fail signal for the bug, you will find the cause — bisection, hypothesis-testing, and instrumentation all just consume that signal. If you do not have one, no amount of staring at code will save you.

Spend disproportionate effort here. Be aggressive. Be creative. Refuse to give up.