diagnose

Diagnose hard bugs through reproducible loops and structured hypotheses.

Updated Apr 28, 2026
One-click install
npx skills add https://github.com/rnaarla/agent_skills --skill diagnose-rnaarla
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: diagnose
Source: https://github.com/rnaarla/agent_skills/tree/main/skills/engineering/diagnose
Command: npx skills add https://github.com/rnaarla/agent_skills --skill diagnose-rnaarla

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve?

Disciplined diagnosis loop for hard bugs and performance regressions. Reproduce → minimise → hypothesise → instrument → fix → regression-test. Use when user says "diagnose this" / "debug this", reports a bug, says something is broken/throwing/failing, or describes a performance regression.

Core Features & Use Cases

  • Systematic reproduction: build deterministic repro loops to isolate the failure.
  • Hypothesis-driven debugging: generate and test focused hypotheses to narrow the cause.
  • Instrumentation-guided fixes: introduce targeted instrumentation and verify regressions are resolved.
  • Use Case: a flaky performance regression is reproduced, narrowed, instrumented, and fixed with a regression test.

Quick Start

Run the diagnose skill and follow the disciplined phases to reproduce, hypothesise, instrument, and fix the bug.

Frequently Asked Questions about diagnose

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I debug a hard bug that is difficult to reproduce?▼

Debugging a hard bug requires a disciplined diagnosis loop: build deterministic reproducible steps to isolate the failure, generate structured hypotheses, and introduce targeted instrumentation to validate fixes.

What is the best way to diagnose a performance regression in a complex software system?▼

Diagnosing a performance regression involves systematic reproduction to minimize variables, hypothesis-driven testing to narrow causes, and instrumentation-guided verification to confirm the regression is resolved.

How do I create a reproducible loop for bug analysis?▼

Creating a reproducible loop for bug analysis requires disciplined, phase-driven workflows that reproduce the failure deterministically, minimize the failing case, and generate focused hypotheses to test.

Can I use hypothesis testing for fixing flaky bugs and regressions?▼

Hypothesis testing for flaky bugs applies structured, phase-driven workflows where you generate focused hypotheses, introduce instrumentation, and verify fixes with regression testing to validate results.

When should I use a systematic diagnosis loop instead of regular debugging?▼

A systematic diagnosis loop is needed for hard bugs, performance regressions, and complex software systems requiring structured hypotheses, deterministic reproduction, and targeted instrumentation rather than ad-hoc debugging.

Does debugging complex software systems require targeted instrumentation?▼

Debugging complex software systems requires targeted instrumentation to validate that regressions are resolved, guiding the fix process and ensuring the structured hypotheses correctly identify the failure cause.