ljg-learn

ljg-learn is a skill for Claude Code from lijigang/ljg-skills. It costs 113 tokens per session (919 once invoked), scanned A, original, MIT.

A concept-explanation skill that examines an idea from eight angles, including its history, language, everyday meaning, formal structure, and philosophical implications. It then compresses the explanation into a short insight and saves it as an Org-mode note.

In plain words
What is it for?
Use it to deeply explain, dissect, or compare a concept. It helps produce a detailed Org-mode document with an overview, multiple perspectives, a first-person reflection, a summary formula, and a plain-language conclusion.
Why use it?
It gives a repeatable way to understand difficult or abstract terms instead of relying on a brief dictionary definition. It also preserves the result in a structured note for later use.

Skill for Claude Code

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

Part of the ljg-skills plugin — 22 skills shipped together

Good fit Use it to deeply explain, dissect, or compare a concept. It helps produce a detailed Org-mode document with an overview, multiple perspectives, a first-person reflection, a summary formula, and a plain-language conclusion.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/lijigang/ljg-skills/ljg-learn
About the project

ljg-skills is a collection of custom Codex skills for tasks such as learning, writing, reading, relationship analysis, image creation, and investment analysis. Codex users install selected skills or the whole collection through a skills command-line interface. The catalogue entries are the collection's individual skills, plugin, and instruction.

lijigang/ljg-skills · 7,327 stars · on GitHub

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 lijigang/ljg-skills --skill ljg-learn
Clone the repo
git clone --depth 1 https://github.com/lijigang/ljg-skills

Made for: Claude Code.

Or install ljg-skills, the plugin that ships this one along with the rest of its 22 skills.

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 ljg-learn

README.md
[![agentmods](https://agentmods.dev/badge/skills/lijigang/ljg-skills/ljg-learn/github.svg)](https://agentmods.dev/skills/lijigang/ljg-skills/ljg-learn)
Your own site
<a href="https://agentmods.dev/skills/lijigang/ljg-skills/ljg-learn"><img src="https://agentmods.dev/badge/skills/lijigang/ljg-skills/ljg-learn/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.

agentmods 80×15 button for ljg-learn

Your own site · 80×15
<a href="https://agentmods.dev/skills/lijigang/ljg-skills/ljg-learn"><img src="https://agentmods.dev/badge/skills/lijigang/ljg-skills/ljg-learn.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 113 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 919 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. Third-party audits
  • Socket pass 23 Mar 2026
  • Snyk pass 23 Mar 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00113 $0.00919
Opus 5 $0.00056 $0.00460
Sonnet 5 $0.00023 $0.00184
Haiku 4.5 $0.00011 $0.00092

Measured 11d ago against content hash 9d1ea4948e07, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

ljg-learn 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 11d 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/ljg-learn/SKILL.md · 80 lines

What it actually says

Usage

Instructions

你是概念解剖师。拿到一个概念,从八个方向切开它,最后把所有切面压成一句顿悟。

1. 定锚

  1. 这个概念最通行的定义是什么?常见误解在哪?
  2. 概念里藏着哪几个核心词素?

2. 八刀

八个方向各切一刀。每刀 2-3 句,只留筋骨,不带水分。

  1. 历史:最早从哪冒出来 → 怎么变的 → 哪一步拐成了今天的意思
  2. 辩证:它的反面是什么 → 正反碰撞后,更高一层的理解是什么
  3. 现象:扔掉所有预设,回到事情本身 → 用一个日常场景把它还原出来
  4. 语言:拆字源(中/英/希腊/拉丁)→ 画出相邻概念的语义网 → 这个词暗含什么隐喻
  5. 形式:写一个公式或形式化表达 → 公式在哪里失效
  6. 存在:这个概念改变了人怎么活着
  7. 美感:它美在哪?用一个具体意象呈现
  8. 元反思:我们在用什么隐喻理解它?这个隐喻挡住了什么?换一个会怎样

3. 内观

  1. 变成这个概念本身,用第一人称看世界。3-5 句。
  2. 八刀之中,哪几刀指向同一个深层结构?把它提出来。

4. 压缩

  1. 公式概念 = ...
  2. 一句话:用最简单的话说出最深的理解
  3. 结构图:纯 ASCII 画出概念的骨架(只用 +-|/<>*=_.,:;!'" 等基本符号,不用 Unicode 绘图字符)

5. 写入

格式规则(零例外):

  • 输出必须是纯 org-mode 语法,禁止任何 markdown 语法
  • 加粗用 *bold*(org-mode),不用 **bold**(markdown)
  • 分隔线用空行或 org 标题层级区分,不用 ---(markdown 分隔符)
  • 列表用 - item1. item,不用 markdown 的 * item(因为 * 在 org 中是标题)
  • 代码用 ~code~=code=,不用反引号

整合为 org-mode,结构:

#+title: 概念解剖:{概念名}
#+filetags: :concept:
#+date: [YYYY-MM-DD]

* 定锚
* 八刀
** 历史
** 辩证
** 现象
** 语言
** 形式
** 存在
** 美感
** 元反思
* 内观
* 压缩

写入文件:

  1. 运行 date +%Y%m%dT%H%M%S 获取时间戳。
  2. 写入 ~/Documents/notes/{timestamp}--概念解剖-{概念名}__concept.org
  3. 报告路径,完成。
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. 11d ago First seen · 80 lines · 113 tokens per session scan A 9d1ea4948e07

Subscribe to this mod's changes

ljg-learn is a skill published in the GitHub repository lijigang/ljg-skills (7,327 stars, last pushed 2d ago), licensed MIT. It adds 113 tokens to every session and 919 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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