dev-debug

A debugging skill for diagnosing and fixing failed tests, build and type errors, runtime crashes, environment problems, and code-style issues.

In plain words
What is it for?
Use it in automatic mode, with a described error, or for errors found during web testing; it can address missing imports, type problems, failing assertions, configuration mistakes, and similar issues.
Why use it?
It organizes different error types around their likely evidence, such as error messages, test differences, stack traces, settings, and lint output. This helps focus the investigation on the relevant project files.

Skill for Claude CodeCodex

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/classmethod/tsumiki/dev-debug
Any agent
npx skills add classmethod/tsumiki --skill dev-debug
Clone the repo
git clone --depth 1 https://github.com/classmethod/tsumiki

Made for: Claude Code, Codex.

Per session 114 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,554 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00114 $0.03554
Opus 5 $0.00057 $0.01777
Sonnet 5 $0.00023 $0.00711
Haiku 4.5 $0.00011 $0.00355

Measured 2d ago against content hash 34a05be961ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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.

skills/dev-debug/SKILL.md · 257 lines

How it starts

The opening of the file, as written. The whole thing — 257 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Dev Debug

テスト失敗、コンパイルエラー、環境問題など、様々なエラーパターンに対応する集中デバッグスキル。エラーをカテゴリ分類し、それぞれに最適な診断・修正戦略を適用する。最小コンテキストでの高速解決を目指す。

前提知識

dev-*スキルフロー内の位置

dev-context → dev-plan → dev-impl → dev-verify
                              ↘ [dev-debug] ↗
                                     ↑
                              dev-webtest → [dev-debug webtest] → 「/dev-webtest retest で再テストしてください」
                                     ↑                                            │
                                     └──────── retest ────────────────────────────┘

dev-impl で解消できないエラーが発生した場合、dev-verify で問題が検出された場合、または dev-webtest で検出された画面系エラーの修正に使用する。

引数フォーマット

/dev-debug                           # 自動検出モード
/dev-debug "エラーメッセージや状況の説明"  # 手動指定モード
/dev-debug webtest                   # webtest エラー修正モード

エラーカテゴリと対応戦略

カテゴリ一覧

カテゴリ 診断アプローチ 典型的な修正
コンパイル/型エラー 型不一致、missing import、構文エラー エラーメッセージの直接分析 型定義修正、import追加
テスト失敗 assertion失敗、タイムアウト 期待値と実際の差分分析 ロジック修正 or テスト修正
ランタイムエラー null参照、パニック、未処理例外 スタックトレース分析 エラーハンドリング追加
環境・設定 依存関係エラー、設定ミス、パス問題 設定ファイル・環境変数チェック 設定修正、依存追加
Lint/フォーマット スタイル違反、未使用変数 Lint出力分析 自動修正 or コード調整
依存関係 バージョン競合、パッケージ不足 lock file/パッケージ分析 バージョン調整、パッケージ追加
webtest エラー 視覚崩れ、a11y違反、レスポンシブ不備、フォームバリデーション不備、シナリオ失敗 error.md の検出内容・再現手順を分析 CSS/HTML修正、バリデーション追加、機能バグ修正

ワークフロー

Step 1: エラー情報の収集と分類

自動検出モード(引数なし)
  1. docs/dev/context.md からテスト実行コマンドを取得する
  2. テストを実行してエラーを収集する
  3. ビルドコマンドがある場合はビルドも実行する
手動指定モード(引数あり、webtest 以外)

ユーザーが提供したエラー情報を分析する。

webtest モード(引数が webtest
  1. docs/dev/webtests/errors/ を Glob で走査し、全 error.md を取得する
  2. 各 error.md を Read し、frontmatter の status: open のものだけ収集する
  3. 0件の場合 →「未解決の webtest エラーはありません」と報告して終了
  4. severity 順にソートする(critical → major → minor)
  5. 各エラーを Step 2 の webtest エラー診断 → Step 3 の修正・検証で順次処理する
  6. 全エラー処理後、Step 4 で報告する(/dev-webtest retest での再テストを案内)
分類判定

Read the full file on GitHub · 257 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. 2d ago First seen · 257 lines · 114 tokens per session scan A 34a05be961ef

Subscribe to this mod's changes

dev-debug is a skill published in the GitHub repository classmethod/tsumiki (974 stars, last pushed 25d ago), licensed MIT. It adds 114 tokens to every session and 3,554 once invoked, about $0.0006 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 2026-08-30.

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