debugging-strategies

debugging-strategies is a skill for Claude Code, Codex from EngineerWithAI/engineerwith-agents. It costs 43 tokens per session (3,025 once invoked), scanned A, a copy of debugging-strategies, MIT.

A guide to investigating bugs and performance problems through reproduction, isolation, experiments, profiling, and root-cause analysis.

In plain words
What is it for?
Use it to analyze stack traces and crash dumps, investigate memory leaks, profile slow code, and track down difficult bugs.
Why use it?
It replaces random changes with a repeatable way to understand unexpected behavior. This is useful for issues in unfamiliar codebases, production systems, and distributed applications.

Skill for Claude CodeCodex

Part of the developer-essentials plugin — 11 skills shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/engineerwithai/engineerwith-agents/debugging-strategies
Any agent
npx skills add EngineerWithAI/engineerwith-agents --skill debugging-strategies
Clone the repo
git clone --depth 1 https://github.com/EngineerWithAI/engineerwith-agents

Made for: Claude Code, Codex.

Or install developer-essentials, the plugin that ships this one along with the rest of its 11 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for debugging-strategies

README.md
[![agentmods](https://agentmods.dev/badge/skills/engineerwithai/engineerwith-agents/debugging-strategies.svg)](https://agentmods.dev/skills/engineerwithai/engineerwith-agents/debugging-strategies)
Your own site
<a href="https://agentmods.dev/skills/engineerwithai/engineerwith-agents/debugging-strategies"><img src="https://agentmods.dev/badge/skills/engineerwithai/engineerwith-agents/debugging-strategies.svg" alt="Measured on agentmods" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,025 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 95% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00043 $0.03025
Opus 5 $0.00022 $0.01512
Sonnet 5 $0.00009 $0.00605
Haiku 4.5 $0.00004 $0.00302

Measured yesterday against content hash 61dbd539f0f9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

debugging-strategies scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

95% identical to debugging-strategies — 152 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/developer-essentials/skills/debugging-strategies/SKILL.md · 528 lines

How it starts

The opening of the file, as written. The whole thing — 528 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debugging Strategies

Transform debugging from frustrating guesswork into systematic problem-solving with proven strategies, powerful tools, and methodical approaches.

When to Use This Skill

  • Tracking down elusive bugs
  • Investigating performance issues
  • Understanding unfamiliar codebases
  • Debugging production issues
  • Analyzing crash dumps and stack traces
  • Profiling application performance
  • Investigating memory leaks
  • Debugging distributed systems

Core Principles

1. The Scientific Method

1. Observe: What's the actual behavior? 2. Hypothesize: What could be causing it? 3. Experiment: Test your hypothesis 4. Analyze: Did it prove/disprove your theory? 5. Repeat: Until you find the root cause

2. Debugging Mindset

Don't Assume:

  • "It can't be X" - Yes it can
  • "I didn't change Y" - Check anyway
  • "It works on my machine" - Find out why

Do:

  • Reproduce consistently
  • Isolate the problem
  • Keep detailed notes
  • Question everything
  • Take breaks when stuck

3. Rubber Duck Debugging

Explain your code and problem out loud (to a rubber duck, colleague, or yourself). Often reveals the issue.

Systematic Debugging Process

Phase 1: Reproduce

## Reproduction Checklist

1. **Can you reproduce it?**
   - Always? Sometimes? Randomly?
   - Specific conditions needed?
   - Can others reproduce it?

2. **Create minimal reproduction**
   - Simplify to smallest example
   - Remove unrelated code
   - Isolate the problem

3. **Document steps**
   - Write down exact steps
   - Note environment details
   - Capture error messages

Phase 2: Gather Information

## Information Collection

1. **Error Messages**
   - Full stack trace
   - Error codes
   - Console/log output

2. **Environment**
   - OS version
   - Language/runtime version
   - Dependencies versions
   - Environment variables

3. **Recent Changes**
   - Git history
   - Deployment timeline
   - Configuration changes

4. **Scope**
   - Affects all users or specific ones?
   - All browsers or specific ones?
   - Production only or also dev?

Read the full file on GitHub · 528 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 528 lines · 43 tokens per session scan A 61dbd539f0f9

Subscribe to this mod's changes

debugging-strategies is a skill published in the GitHub repository EngineerWithAI/engineerwith-agents (4 stars, last pushed 7mo ago), licensed MIT. It adds 43 tokens to every session and 3,025 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 95% identical to debugging-strategies, differing in 152 lines, and is treated as a copy.

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