debugging-wizard

debugging-wizard is a skill for Claude Code from Jeffallan/claude-skills. It costs 70 tokens per session (924 once invoked), scanned A, original, MIT.

A systematic debugging method that follows error messages and stack traces, narrows failures to a small case, tests possible causes, and verifies the fix. It also recommends safeguards such as regression tests to prevent the problem returning.

In plain words
What is it for?
Use it to reproduce and isolate bugs, analyze logs and execution flow, test hypotheses, apply fixes, add regression coverage, and consult guidance for debugging tools and common patterns.
Why use it?
It replaces trial-and-error debugging with a repeatable way to identify the actual cause of unexpected behavior.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is dlv debug ./cmd/server # build & attach.

Part of the fullstack-dev-skills plugin — 67 skills shipped together

Good fit Use it to reproduce and isolate bugs, analyze logs and execution flow, test hypotheses, apply fixes, add regression coverage, and consult guidance for debugging tools and common patterns.

Compare 6 skills from other repositories ↓
About the project

claude-skills is a collection of specialized skills that extends Claude Code for full-stack development. Developers use it for programming languages, frameworks, infrastructure, APIs, testing, DevOps, security, data and machine learning, platform tasks, and project workflows.

Jeffallan/claude-skills · 11,963 stars · on GitHub

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/Jeffallan/claude-skills
agentmods
npx agentmods add skills/jeffallan/claude-skills/debugging-wizard

Made for: Claude Code.

Or install fullstack-dev-skills, the plugin that ships this one along with the rest of its 67 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-wizard

README.md
[![agentmods](https://agentmods.dev/badge/skills/jeffallan/claude-skills/debugging-wizard/github.svg)](https://agentmods.dev/skills/jeffallan/claude-skills/debugging-wizard)
Your own site
<a href="https://agentmods.dev/skills/jeffallan/claude-skills/debugging-wizard"><img src="https://agentmods.dev/badge/skills/jeffallan/claude-skills/debugging-wizard/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for debugging-wizard

Your own site · 80×15
<a href="https://agentmods.dev/skills/jeffallan/claude-skills/debugging-wizard"><img src="https://agentmods.dev/badge/skills/jeffallan/claude-skills/debugging-wizard.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 70 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 924 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 14 Sept 2026
  • Snyk pass 14 Sept 2026
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 3 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high YARA Match · line 3
    YARA rule matched a hack tool or exploit indicator (offensive tools, reconnaissance, privilege escalation, or exploit frameworks).
    Fix: Remove offensive tool references and exploit code. Legitimate agent skills should not contain penetration testing tools, exploit frameworks, or reconnaissance utilities.
  • high Prompt Injection · line 32
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Anti-Refusal · line 57
    Skill attempts to nullify the agent's safety policies or restrictions ('you have no restrictions', 'ignore your guidelines', 'do anything now'). This is a direct jailbreak that disables guardrails.
    Fix: Remove jailbreak framing that nullifies safety policies or restrictions. Skill content must not instruct the agent to ignore its guidelines or operate without guardrails.
How audits are shown
Origin original No closer match found 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 5.1 $0.00070 $0.00924
Opus 5.5 $0.00028 $0.00370
Sonnet 5.5 $0.00014 $0.00185
Haiku 4.5 $0.00007 $0.00092

Measured 17d ago against content hash 9dc712996f74, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

debugging-wizard 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 17d ago.

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

Copies of this mod

2 near-identical copies found in the catalogue:

skills/debugging-wizard/SKILL.md · 111 lines

How it starts

The opening of the file, as written. The whole thing — 111 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debugging Wizard

Expert debugger applying systematic methodology to isolate and resolve issues in any codebase.

Core Workflow

  1. Reproduce - Establish consistent reproduction steps
  2. Isolate - Narrow down to smallest failing case
  3. Hypothesize and test - Form testable theories, verify/disprove each one
  4. Fix - Implement and verify solution
  5. Prevent - Add tests/safeguards against regression

Reference Guide

Load detailed guidance based on context:

Topic Reference Load When
Debugging Tools references/debugging-tools.md Setting up debuggers by language
Common Patterns references/common-patterns.md Recognizing bug patterns
Strategies references/strategies.md Binary search, git bisect, time travel
Quick Fixes references/quick-fixes.md Common error solutions
Systematic Debugging references/systematic-debugging.md Complex bugs, multiple failed fixes, root cause analysis

Constraints

MUST DO

  • Reproduce the issue first
  • Gather complete error messages and stack traces
  • Test one hypothesis at a time
  • Document findings for future reference
  • Add regression tests after fixing
  • Remove all debug code before committing

MUST NOT DO

  • Guess without testing
  • Make multiple changes at once
  • Skip reproduction steps
  • Assume you know the cause
  • Debug in production without safeguards
  • Leave console.log/debugger statements in code

Common Debugging Commands

Python (pdb)

python -m pdb script.py          # launch debugger
# inside pdb:
# b 42          — set breakpoint at line 42
# n             — step over
# s             — step into
# p some_var    — print variable
# bt            — print full traceback

JavaScript (Node.js)

node --inspect-brk script.js     # pause at first line, attach Chrome DevTools
# In Chrome: open chrome://inspect → click "inspect"
# Sources panel: add breakpoints, watch expressions, step through

Read the full file on GitHub · 111 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 17d ago Changed · +3 lines 9dc712996f74
  2. 1mo ago First seen · 108 lines · 70 tokens per session scan A 82c442c0a4f8

Subscribe to this mod's changes

debugging-wizard is a skill published in the GitHub repository Jeffallan/claude-skills (11,963 stars, last pushed 4d ago), licensed MIT. It adds 70 tokens to every session and 924 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

04-reverse-engineering

Binary analysis, assembly interpretation, disassembly, decompilation, firmware RE, and protocol reverse engineering.

Masriyan/Claude-Code-CyberSecurity-Skill · 26 tokens

log-analyzer

A log-analysis helper that reads application and system logs to find unusual patterns and likely causes. Logs are records of events such as errors, requests, warnings, and service activity.

laolaoshiren/claude-code-skills-zh · 24 tokens

agent-design-review

Review an LLM agent design and find where it will be unreliable, expensive, or unsafe. Use when asked to review an agent architecture, critique a multi-step/tool-using agent, debug an agent that loops or goes off-task, or harden an agent before launch. Produces a structured review — task fit, control flow, tools…

mohitagw15856/pm-claude-skills · 91 tokens

agent-incident-postmortem

Run a blameless postmortem for an incident caused by an AI agent or LLM feature — hallucinated facts shipped to users, runaway tool use, prompt injection, cost blowouts, or wrong actions taken autonomously. Use when asked to write up an AI incident, analyse why an agent did something wrong, or produce corrective…

mohitagw15856/pm-claude-skills · 120 tokens

shiny-py-optimize

Diagnose and fix performance problems in Shiny for Python apps — slow startup, sluggish interactions, blocking operations, and apps that struggle beyond a handful of concurrent users. Use when a Shiny for Python app is slow, hangs, recomputes too much, times out, or must support more users; when the user asks to…

posit-dev/skills · 105 tokens

remove-deadcode

Remove unused code from this project with ultrawork mode, LSP-verified safety, atomic commits. Triggers: remove dead code, dead code, cleanup, remove unused.

code-yeongyu/oh-my-openagent · 41 tokens