What problem does it solve? Hard bugs and flaky performance regressions resist casual code reading and guesswork. This Skill enforces a disciplined diagnosis loop that builds a tight, deterministic reproduction signal before any hypothesis is tested, preventing wasted time on wrong fixes. ## Core Features & Use Cases - Feedback Loop Construction: Builds a red-capable, deterministic, fast reproduction command using failing tests, curl scripts, headless browsers, trace replay, fuzz loops, or bisection harnesses. - Structured Six-Phase Process: Guides reproduction and minimization, ranked falsifiable hypothesis generation, one-variable-at-a-time instrumentation, regression-test-first fixing, and cleanup with post-mortem. - Human-in-the-Loop Fallback: Ships a bash template script for driving a human through manual reproduction steps when automation is impossible, capturing observations as parseable output. - Use Case: A user reports that an export endpoint intermittently throws a 500 error. The Skill builds a curl-based loop that reproduces the failure at a high rate, minimizes the input, tests ranked hypotheses with tagged debug logs, and lands a fix with a regression test. ## Quick Start Ask the agent to diagnose the bug where the export button throws an error, and have it build a reproduction loop before proposing any fix.
