diagnosing-bugs

Diagnose hard bugs and performance regressions through a six-phase feedback-loop workflow.

Updated Jul 30, 2026
One-click install
npx skills add https://github.com/j172/bid --skill diagnosing-bugs-j172
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: diagnosing-bugs
Source: https://github.com/j172/bid/tree/main/.agents/skills/diagnosing-bugs
Command: npx skills add https://github.com/j172/bid --skill diagnosing-bugs-j172

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve? Hard bugs and performance regressions stall when developers jump straight to hypotheses without a reproducible signal. This Skill enforces a disciplined diagnosis loop that builds a tight pass/fail feedback signal first, then reproduces, minimises, hypothesises, instruments, fixes, and cleans up. ## Core Features & Use Cases - Feedback loop construction: Ten ranked strategies for building a red-capable reproduction command, from failing tests and curl scripts to headless browser runs, trace replay, fuzz loops, and git bisect harnesses. - Structured hypothesis testing: Generates 3-5 ranked, falsifiable hypotheses before testing, then maps each instrumentation probe to a specific prediction with tagged debug logs for easy cleanup. - Regression test and post-mortem: Turns the minimised repro into a failing regression test at a correct seam, verifies the fix, removes instrumentation, and records the confirmed root cause. - Use Case: A user reports that an export endpoint intermittently returns corrupted data. The Skill guides building a deterministic loop that reproduces the corruption, minimising the input, ranking hypotheses, and landing a fix with a regression test. ## Quick Start Ask the agent to diagnose the bug where the export endpoint intermittently returns corrupted data and have it build a reproduction loop first.

Frequently Asked Questions about diagnosing-bugs

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

FAQPage Schema
How do I debug a bug that I cannot reproduce consistently?

Non-deterministic bugs are handled by raising the reproduction rate rather than seeking a clean repro. Loop the trigger 100 times, parallelise, add stress, narrow timing windows, or inject sleeps until the failure rate is high enough to debug against.

How to build a feedback loop for debugging a failing test?

Start with a failing test at whatever seam reaches the bug, then try curl scripts, CLI invocations with fixture inputs, headless browser scripts, trace replay, or a throwaway harness. The loop must assert the user's exact symptom and run deterministically in seconds.

What should I do when I cannot build any reproduction loop?

Stop and say so explicitly, listing what you tried. Ask the user for environment access, a captured artifact such as a HAR file or core dump, or permission to add temporary production instrumentation instead of hypothesising blindly.

Why write the regression test before the fix?

Writing the regression test first proves the test actually catches the bug by watching it fail before the fix and pass after. It only applies when a correct seam exists that exercises the real bug pattern as it occurs at the call site.

How are performance regressions diagnosed differently from functional bugs?

Performance regressions skip log-based probing in favor of measurement. Establish a baseline with a timing harness, profiler, or query plan, then bisect against that baseline, measuring first and fixing second.