dev-navigate

A developer-navigation guide that asks what kind of work you want to do and recommends the appropriate development workflow. It covers planning, implementation, verification, debugging, and web testing.

In plain words
What is it for?
Use it to choose a workflow for shaping an idea, changing existing code, starting implementation, checking a website, updating specifications, or fixing errors.
Why use it?
Large development toolsets can make it unclear where to begin or which procedure should come next.

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

Made for: Claude Code, Codex.

Per session 110 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,170 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 $0.00110 $0.03170
Opus 5 $0.00055 $0.01585
Sonnet 5 $0.00022 $0.00634
Haiku 4.5 $0.00011 $0.00317

Measured 2d ago against content hash edef745f8086, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

dev-navigate 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-navigate/SKILL.md · 281 lines

How it starts

The opening of the file, as written. The whole thing — 281 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Dev Navigate

開発者がやりたいことを対話で把握し、最適なtsumikiスキルの開始ポイントを提案するナビゲーションスキル。提案後、ユーザーの承認があればそのスキルを起動する。

対象スキル一覧

スキル 概要
dcs:feature-rubber-duck アイデアを整理して実現可能なPRDを作成する
dcs:incremental-dev 既存コードへの段階的な機能追加の計画を立案する
dcs:impact-analysis 変更の影響範囲を分析する
dev-plan 要件をタスク分解して実装計画を立てる
dev-impl テストファースト実装を行う(Plan指定 or クイックモード)
dev-run impl → verify → debug を自動で連続実行する
dev-verify Plan 単位でテスト・ビルド・Lint を一括検証する
dev-debug エラーをカテゴリ別に診断して修正する(webtest エラーにも対応)
dev-screen-spec ソースコードまたは受け入れ条件から画面仕様を自動生成・差分更新する
dev-webtest-plan dev-plan の成果物から Web テスト計画を生成する。画面仕様の差分更新にも対応
dev-webtest Playwright で画面の動作確認・視覚テストを行い、問題を検出・記録する

ワークフロー

Step 1: メイン質問(Q1)

AskUserQuestion で以下を質問する:

質問: 「今やりたいことに一番近いのはどれですか?」

選択肢 説明
アイデアを整理してPRDにしたい まだ構想段階。アイデアを実現可能なPRDに落とし込みたい
既存コードに変更を加えたい 既に動いているコードに機能追加や変更をしたい
すぐに実装・修正に入りたい 要件やplanは明確。実装作業を始めたい
テスト・画面確認をしたい 実装済みのコードの検証や Web 画面の動作確認をしたい
エラーやバグを修正したい テスト失敗、ビルドエラー、画面の不具合などを直したい
画面仕様やテスト計画を最新化したい ソースコード変更後に画面仕様やテスト計画を差分更新したい

Step 2: 結果の判定

Q1の回答に応じて分岐する。

Q1 = 「アイデアを整理してPRDにしたい」

提案スキル: dcs:feature-rubber-duck

提案メッセージ:

## Nav 結果

**推奨スキル:** `/dcs:feature-rubber-duck`

アイデアを対話で深掘りし、実現可能なPRDドキュメントに整理します。
PRDが完成したら `/dev-plan` でタスク分解に進めます。

**推奨フロー:**
1. `dcs:feature-rubber-duck` — アイデアをPRDに整理
2. `dev-plan` — PRDからタスク分解
3. `dev-impl` — タスクごとに実装
Q1 = 「既存コードに変更を加えたい」

追加質問 Q2 に進む(Step 3)。

Q1 = 「すぐに実装・修正に入りたい」

提案スキル: dev-impl

提案メッセージ:

## Nav 結果

**推奨スキル:** `/dev-impl`

- Planとタスクがある場合: `/dev-impl <plan-name> <task-id>`
- 小さな修正の場合: `/dev-impl "修正内容"`(クイックモード)
- 複数タスクを自動実行する場合: `/dev-run <plan-name> <from> <to>`

Planがまだない場合は先に `/dev-plan` でタスク分解することも検討してください。
Q1 = 「テスト・画面確認をしたい」

追加質問 Q2b に進む(Step 3b)。

Q1 = 「エラーやバグを修正したい」

提案スキル: dev-debug

提案メッセージ:

## Nav 結果

**推奨スキル:** `/dev-debug`

- テスト失敗やビルドエラーの自動検出: `/dev-debug`
- 特定のエラーを指定: `/dev-debug "エラーメッセージ"`
- Web 画面テストで検出されたエラー: `/dev-debug webtest`

修正後は `/dev-verify` で回帰確認、Web 画面の場合は `/dev-webtest retest` で再テストできます。

Read the full file on GitHub · 281 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 · 281 lines · 110 tokens per session scan A edef745f8086

Subscribe to this mod's changes

dev-navigate is a skill published in the GitHub repository classmethod/tsumiki (974 stars, last pushed 25d ago), licensed MIT. It adds 110 tokens to every session and 3,170 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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