core

core is a skill for Claude Code from muji-j/jp-power-tools. It costs 168 tokens per session (1,369 once invoked), scanned A, original, MIT.

A reference guide to Japan’s electricity market, including trading markets, supply and demand, settlement, and industry terms.

In plain words
What is it for?
Use it when researching electricity trading, generation, retail supply, balancing, transmission, capacity, or regulatory procedures in Japan.
Why use it?
It explains the Japanese rules and vocabulary needed to interpret market data and operational decisions correctly.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the jp-power plugin — 5 skills, 7 commands shipped together

Good fit Use it when researching electricity trading, generation, retail supply, balancing, transmission, capacity, or regulatory procedures in Japan.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/muji-j/jp-power-tools/core
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 muji-j/jp-power-tools --skill core
Clone the repo
git clone --depth 1 https://github.com/muji-j/jp-power-tools

Made for: Claude Code.

Or install jp-power, the plugin that ships this one along with the rest of its 5 skills, 7 commands.

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 core

README.md
[![agentmods](https://agentmods.dev/badge/skills/muji-j/jp-power-tools/core.svg)](https://agentmods.dev/skills/muji-j/jp-power-tools/core)
Your own site
<a href="https://agentmods.dev/skills/muji-j/jp-power-tools/core"><img src="https://agentmods.dev/badge/skills/muji-j/jp-power-tools/core.svg" alt="Measured on agentmods" height="20"></a>
Per session 168 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,369 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 $0.00168 $0.01369
Opus 5 $0.00084 $0.00685
Sonnet 5 $0.00034 $0.00274
Haiku 4.5 $0.00017 $0.00137

Measured 8d ago against content hash a6d72d61c3d2, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

core 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 8d 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.

jp-power/skills/core/SKILL.md · 56 lines

What it actually says

電力市場ドメイン — 基礎・用語 (core)

概要

日本の電力市場(卸取引・需給・制度)の実務のための汎用ドメイン知識。発電・小売・需給管理・トレーディングいずれの立場でも使える。特定企業固有の手順・数値は含まない。

基本骨格: 1日 = 48コマ(30分単位) / 計画値同時同量 の下で計画-実績の差分はインバランスとして精算 / 市場はスポット(前日)・時間前(当日)・需給調整(調整力)・容量の4層構造。

表記方針: 説明は日本語、公式用語はそのまま日本語表記で用いる(社外資料・報告書でそのまま使えるように)。

参照ファイル

ファイル 内容 読むタイミング
references/terms.md 用語集(市場・計画・調整力・容量・小売規制・託送・非化石・GX・計量精算・組織/機関・予測運用) 用語・概念が出る全作業の基本参照

関連スキル(同一プラグイン jp-power)

  • jp-power:markets — 市場別の規則・日次タイムライン・年間日程・制度改正(../markets/references/markets.md
  • jp-power:data — 公開情報源・データ取得(../data/references/sites.md, ../data/references/data-sources.md
  • jp-power:ops — 業務フロー・計算/予測(../ops/references/workflows.md, ../ops/references/calc.md
  • jp-power:regwatch — 制度ウォッチ(官の公表物の新規取得・業界影響サマリ、/power-news/power-verify

用語はこの core が起点。他スキルは上記の相対パスで terms.md を参照する。

鉄則(全作業共通)

  1. 情報収集は data スキルの sites.md 一次ソース直行が基本。 記憶上の URL で直接アクセスしない — このドメインはサイト移転が頻繁(監視委 emsc→egc.meti.go.jp、HJKS は hjks.jepx.or.jp、OCCTO ページ移動など)。記憶と sites.md が食い違えば sites.md を優先。
  2. 時刻・数値を記憶で断定しない。 締切・公表時刻、インバランスのアンカー値などは markets スキルの markets.md を確認し、制度改正の可能性があれば公式サイトで再確認。
  3. 単位混同に注意。 提出先ごとに kW/kWh/MW が異なる。コマ(30分)単位のため kW→kWh 換算は ÷2(→ ops の calc.md)。
  4. 汎用配布用スキルであり、企業固有情報(社名・内部URL・実際の入札価格/数量・発電所実名)は含まない — 作業成果物にもみだりに書かない。企業固有の手順は各組織の内部文書で別管理する。

コマンド(プラグイン共通)

  • /power-brief — 需給ブリーフィングHTMLダッシュボード生成。
  • /power-get — 公開データを対話取得し CSV でダウンロード。
  • /power-term — 電力市場の用語を用語集(terms.md)から即座に調べて説明。
  • /power-news — 官の新規公表物を取得し業界影響を汎用サマリで報告(制度ウォッチ)。
  • /power-verify — 情報源URL・数値・年間日程を公式ソースと突合(+制度変更の検知)。
  • /power-bid — 需給調整市場の応札CSV下書き。
  • /power-setup — Python・ライブラリ実行環境の点検・導入。
  • 各コマンドは自然文でも起動できる(不足引数は提案→確認)。常用エリアは /power-setup で登録可能。

(詳細は各スキルおよび scripts/README.md。)

更新

現行バージョン: v0.12.0(2026-07-30)。制度・URL は 2026-07-30 時点。

いずれかのスキル内容を変更したらバージョン表記を更新し、制度改正を確認したら該当参照ファイルを更新する。定期点検には /power-verify を使う。

Files

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.

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. 8d ago First seen · 56 lines · 168 tokens per session scan A a6d72d61c3d2

Subscribe to this mod's changes

core is a skill published in the GitHub repository muji-j/jp-power-tools (1 stars, last pushed 1mo ago), licensed MIT. It adds 168 tokens to every session and 1,369 once invoked, about $0.0008 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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