diagnose

Diagnose hard bugs through reproduce, hypothesise, instrument, fix, and verify phases.

356|59|Updated Apr 29, 2026
One-click install
npx skills add https://github.com/amazingloft999-droid/mattpocock-skills --skill diagnose-amazingloft999-droid
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: diagnose
Source: https://github.com/amazingloft999-droid/mattpocock-skills/tree/main/skills/engineering/diagnose
Command: npx skills add https://github.com/amazingloft999-droid/mattpocock-skills --skill diagnose-amazingloft999-droid

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve?

Disciplined diagnosis loop for hard bugs. 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

  • Establish fast, deterministic feedback loops to identify root causes.
  • Guide hypothesis-driven investigation with structured phases and guardrails.
  • Instrument code, collect traces, and verify fixes with regression tests across local and CI environments.

Quick Start

Activate the diagnose skill to establish a fast, deterministic feedback loop for hard bugs.

Frequently Asked Questions about diagnose

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

FAQPage Schema
What is a structured debugging loop for diagnosing hard bugs?

A structured debugging loop guides hypothesis-driven investigation through phases: reproduce, minimise, hypothesise, instrument, fix, and regression-test, ensuring reliable signal collection for root cause identification.

How do I reproduce and minimise a hard bug across different codebases?

You reproduce and minimise a hard bug by establishing a fast, deterministic feedback loop that captures traces and instruments code, enabling repeatable experimentation and reliable signal collection for root cause triage.

Can I use this structured debugging approach for performance regressions in CI environments?

Yes, you can use this approach for performance regressions in CI environments; it guides hypothesis-driven investigation, instruments code to collect traces, and verifies fixes with regression tests across local and CI setups.

Do I need to run tests and instrument code to diagnose hard bugs?

Yes, diagnosing hard bugs requires the ability to run tests, capture traces, and instrument code to produce reliable signals for debugging and to verify fixes through regression-testing.

What is the best way to triage a bug that is throwing or failing intermittently?

The best way to triage an intermittent or failing bug is to use a disciplined diagnosis loop from reproduction to regression-testing, enabling repeatable experimentation and fast triage to isolate the root cause.

When should I not use a hypothesis-driven debugging loop?

You should avoid a hypothesis-driven debugging loop for trivial bugs where the root cause is immediately visible, as the structured phases of reproduction, instrumentation, and regression-testing add unnecessary overhead.