dev:debug

dev:debug is a skill for Claude Code from atournayre/claude-marketplace. It costs 17 tokens per session (666 once invoked), scanned A, original, MIT.

A troubleshooting workflow for analyzing an error message or stack trace, which records the chain of calls that led to a failure. It examines the relevant source code and context.

In plain words
What is it for?
Use it to investigate syntax, runtime, configuration, or logic errors and, when requested, plan or apply a resolution.
Why use it?
It turns a vague failure into a categorized diagnosis and identifies where the problem occurs.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: model in frontmatter.

Part of the dev plugin — 25 skills, 8 agents shipped together

Good fit Use it to investigate syntax, runtime, configuration, or logic errors and, when requested, plan or apply a resolution.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/atournayre/claude-marketplace/debug
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.

Any agent
npx skills add atournayre/claude-marketplace --skill debug
Clone the repo
git clone --depth 1 https://github.com/atournayre/claude-marketplace

Made for: Claude Code.

Or install dev, the plugin that ships this one along with the rest of its 25 skills, 8 agents.

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 dev:debug

README.md
[![agentmods](https://agentmods.dev/badge/skills/atournayre/claude-marketplace/debug/github.svg)](https://agentmods.dev/skills/atournayre/claude-marketplace/debug)
Your own site
<a href="https://agentmods.dev/skills/atournayre/claude-marketplace/debug"><img src="https://agentmods.dev/badge/skills/atournayre/claude-marketplace/debug/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 dev:debug

Your own site · 80×15
<a href="https://agentmods.dev/skills/atournayre/claude-marketplace/debug"><img src="https://agentmods.dev/badge/skills/atournayre/claude-marketplace/debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 666 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.
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 $0.00017 $0.00666
Opus 5 $0.00009 $0.00333
Sonnet 5 $0.00003 $0.00133
Haiku 4.5 $0.00002 $0.00067

Measured 9d ago against content hash e893c5c6402d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

dev:debug 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 9d 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.

dev/skills/debug/SKILL.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debug - Analyse et Résolution d'Erreurs

Instructions à Exécuter

IMPORTANT : Exécute ce workflow étape par étape :

Analyser une erreur (message ou stack trace) et proposer/appliquer résolution.

Variables

  • ERROR_INPUT: $ARGUMENTS
  • ERROR_TYPE: Type détecté (simple message vs stack trace)
  • CONTEXT_FILES: Fichiers pertinents
  • RESOLUTION_PLAN: Plan structuré si résolution demandée

Détection Automatique

Le système détecte automatiquement :

  • Stack trace : Parsing + formatage + analyse approfondie
  • Message simple : Analyse directe + diagnostic

Patterns stack trace :

  • Fatal error:, Uncaught, Exception, Error:
  • Présence de at <file>:<line>
  • Multiple lignes avec indentation/numéros

Workflow

1. Identification Type

Si stack trace détectée :

  • Parser trace (type, message, fichier:ligne, call stack)
  • Formater hiérarchiquement
  • Lire code source ligne incriminée
  • Générer rapport /tmp/stack-trace-analysis-[timestamp].md

Si message simple :

  • Catégoriser (syntaxe, runtime, logique, config)
  • Extraire infos contextuelles

2. Analyse Contexte

  • Examiner fichiers mentionnés
  • Analyser logs récents corrélés
  • Vérifier environnement (deps, config)
  • Identifier changements récents (git)

3. Diagnostic

  • Cause racine vs symptômes
  • Impact et criticité
  • Solutions possibles + trade-offs
  • Priorisation

4. Solutions

Stack trace : 3 niveaux

  1. Quick Fix ⚡ : Rapide, symptôme
  2. Recommandée ✅ : Équilibrée, cause
  3. Long-terme 🎯 : Robuste, prévention

Message simple : Plan résolution

  • Étapes séquencées
  • Tests validation
  • Rollbacks prévus
  • Risques estimés

5. Exécution (optionnel)

Si utilisateur demande résolution :

  • Appliquer corrections pas à pas
  • Valider chaque modif
  • Vérifier résolution complète
  • Documenter changements

Exemples

# Stack trace PHP
/dev:debug "Fatal error: Call to undefined method User::getName()"

# Fichier log
/dev:debug /var/log/app.log

# Message NPM
/dev:debug "npm ERR! missing script: build"

Read the full file on GitHub · 108 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. 9d ago First seen · 108 lines · 17 tokens per session scan A e893c5c6402d

Subscribe to this mod's changes

dev:debug is a skill published in the GitHub repository atournayre/claude-marketplace (9 stars, last pushed 6mo ago), licensed MIT. It adds 17 tokens to every session and 666 once invoked, about $0.0001 per session on Opus 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 2026-08-31.

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