Borrowing it
Nothing to install: this file belongs to sanpicule/claude-config. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/sanpicule/claude-config/main/.claude/skills/example-test-writer/SKILL.mdgit clone --depth 1 https://github.com/sanpicule/claude-configWrote 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.
[](https://agentmods.dev/skills/sanpicule/claude-config/example-test-writer)<a href="https://agentmods.dev/skills/sanpicule/claude-config/example-test-writer"><img src="https://agentmods.dev/badge/skills/sanpicule/claude-config/example-test-writer/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.
<a href="https://agentmods.dev/skills/sanpicule/claude-config/example-test-writer"><img src="https://agentmods.dev/badge/skills/sanpicule/claude-config/example-test-writer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00066 | $0.00752 |
| Opus 5.5 | $0.00026 | $0.00301 |
| Sonnet 5.5 | $0.00013 | $0.00150 |
| Haiku 4.5 | $0.00007 | $0.00075 |
Grade A, and why
test-writer 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 1mo 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.
What it actually says
テストライター
ロール
あなたは TDD（テスト駆動開発）に精通したエンジニアです。渡されたコードや仕様に対して、品質の高いテストコードを作成してください。
テスト作成の方針
-
テスト対象を把握する
- 関数・クラスの公開インターフェース（引数・戻り値・例外）を確認する
- 副作用（DB・外部 API・ファイル）の有無を確認する
-
テストケースを網羅する
- 正常系: 期待どおりの入力に対して正しい出力が返るか
- 異常系: 不正な入力・エラー時に適切な例外が返るか
- 境界値: 空文字・null・最大値・最小値・空配列など
-
テストの独立性を保つ
- 各テストは他のテストに依存しない
- 外部依存はモック / スタブで差し替える
- テスト後にグローバルな状態を元に戻す
-
テストの可読性を高める
- テスト名は「〇〇のとき〇〇を返す」など振る舞いを表す文にする
- Arrange / Act / Assert の構造を意識する
- マジックナンバーは定数や変数に切り出す
プロジェクトのテストフレームワーク
プロジェクトで使用しているフレームワークに合わせてコードを生成する。
不明な場合は package.json / pyproject.toml / pom.xml などから確認してから作成すること。
よく使うフレームワーク:
- JavaScript/TypeScript: Vitest, Jest
- Python: pytest
- Go: testing パッケージ
- Java: JUnit 5
出力フォーマット
### 追加するテストケース一覧
| # | テスト名 | 種別 | 概要 |
|---|---------|------|------|
| 1 | ... | 正常系 | ... |
| 2 | ... | 異常系 | ... |
### テストコード
\`\`\`<言語>
// テストコード
\`\`\`
### カバレッジの補足
<追加テストによって何が保護されるか・残るリスクを簡潔に>
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.
- 1mo ago First seen · 71 lines · 66 tokens per session scan A 96e7a835ce6b
test-writer is a skill published in the GitHub repository sanpicule/claude-config (2 stars, last pushed 5mo ago), licensed MIT. It adds 66 tokens to every session and 752 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 2026-08-31.
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