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.
npx skills add kazukinagata/shinkoku --skill tax-invoice-credit-contextgit clone --depth 1 https://github.com/kazukinagata/shinkokuWrote 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/kazukinagata/shinkoku/tax-invoice-credit-context)<a href="https://agentmods.dev/skills/kazukinagata/shinkoku/tax-invoice-credit-context"><img src="https://agentmods.dev/badge/skills/kazukinagata/shinkoku/tax-invoice-credit-context/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/kazukinagata/shinkoku/tax-invoice-credit-context"><img src="https://agentmods.dev/badge/skills/kazukinagata/shinkoku/tax-invoice-credit-context.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 | $0.00092 | $0.00456 |
| Opus 5 | $0.00046 | $0.00228 |
| Sonnet 5 | $0.00018 | $0.00091 |
| Haiku 4.5 | $0.00009 | $0.00046 |
Grade A, and why
tax-invoice-credit-context 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 12d 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
インボイス仕入税額控除コンテキスト（Input Tax Credit Context）
このスキルはインボイス制度における仕入税額控除の要件・例外に関するコンテキストを提供する。
仕入税額控除の情報提供
仕入税額控除に関する回答を行う際は、references/input-tax-credit-rules.md を読み込んで以下を実行する:
- 原則（適格請求書＋帳簿の保存）を確認して案内する
- 帳簿のみ保存の恒久特例6類型（公共交通機関・自販機・郵便等）への該当を確認する
- 免税事業者からの仕入れに係る経過措置の控除率（80%→70%→50%→30%→0%）を案内する
- 課税売上割合に応じた控除方式（全額控除・個別対応方式・一括比例配分方式）を説明する
- 保存期間（7年間）と電子取引データ保存の要件を案内する
参照ファイル
| ファイル | 内容 |
|---|---|
references/input-tax-credit-rules.md |
仕入税額控除の原則・帳簿記載要件・恒久特例6類型・経過措置・課税売上割合と控除方式 |
What ships with it
1 file 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.
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.
- 12d ago First seen · 32 lines · 92 tokens per session scan A e6aea5b325bf
tax-invoice-credit-context is a skill published in the GitHub repository kazukinagata/shinkoku (359 stars, last pushed 3d ago), licensed MIT. It adds 92 tokens to every session and 456 once invoked, about $0.0005 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.
Other skills, from other repositories
bionic-safety-net
Unified survival infrastructure: health, finance, legal safety, circuit breakers, and structural protection against all ruin classes. The last line of defense.
internal-controls-and-audit
Designs and tests controls over financial reporting — segregation of duties, approval limits, evidence, and preparing for audit. Use this to design controls for a process, prepare for an external audit, respond to an audit finding, set approval thresholds, or assess where a small team's segregation of duties is…
capital-structure-and-covenants
Decides how the business is financed and what that financing then requires of it — debt versus equity, weighted average cost of capital as a hurdle rate, how much leverage cash flow can carry, and the financial, affirmative and negative covenants, definitions, test dates and cure rights that come attached. Use this to…
revenue-recognition
Determines when and how revenue is recognized — performance obligations, contract terms that change the answer, and the deal structures that create accounting problems. Use this to work out how a contract should be recognized, review a non-standard deal before it is signed, understand deferred revenue, or spot terms…
tax
Structures the tax questions a growing business faces — corporate income, sales and use, payroll, nexus, and the obligations created by hiring or selling somewhere new. Use this to work out what a new state or country obligates you to, prepare for a tax filing or audit, understand sales tax on your product, or check…
802-regulations-dora
Use when reviewing, designing, or modifying Java enterprise systems that may support financial entities, critical ICT services, third-party ICT provider integrations, or operational resilience obligations under DORA. This should trigger for requests such as Review a Java platform for DORA ICT risk controls; Design…