explain

A plain-language explanation tool for understanding complex ideas, formulas, models, systems, and technical terms from their basic parts.

In plain words
What is it for?
It helps explain mathematics, prediction or scoring models, system designs, and other concepts when a first-principles breakdown is needed.
Why use it?
It makes unfamiliar subjects easier to follow by starting with the end result and showing how the inputs lead to it.

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/kv0906/pm-kit/explain
Any agent
npx skills add kv0906/pm-kit --skill explain
Clone the repo
git clone --depth 1 https://github.com/kv0906/pm-kit

Made for: Claude Code, Codex.

Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 838 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 $0.00055 $0.00838
Opus 5 $0.00028 $0.00419
Sonnet 5 $0.00011 $0.00168
Haiku 4.5 $0.00006 $0.00084

Measured 2d ago against content hash 8c8dfdd7fed0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

explain 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.

.claude/skills/explain/SKILL.md · 98 lines

How it starts

The opening of the file, as written. The whole thing — 98 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Explain — First Principles Concept Breaker

Reverse-engineer complex concepts into natural language. No jargon. Start from the end result and work backwards to raw inputs.

Input format: /explain [concept, formula, model, or paste]

What You Do

Take any complex input — math formula, scoring model, system design, methodology, technical concept — and explain it so a beginner can explain it back.

Input

User provides:

  • A math problem, equation, methodology, scoring system, model, or abstract concept
  • Optional: context of what it's used for (finance, physics, prediction markets, etc.)

Reasoning Process (follow in order)

Work through these steps internally before writing the explanation:

A. Find the End Goal — What is the final output? Translate it to a real-world result (money, score, probability, decision, ranking).

B. Find the Inputs — What raw information goes in? Translate each to real-world meaning.

C. Find How Value Is Earned — What actions/factors increase the result? What decreases it?

D. Find Comparisons — Does the model compare things? (person vs person, side vs side, time vs time). Explain as "share of total" or "relative contribution".

E. Find Rules and Boundaries — Minimums, maximums, penalties, special cases. Explain why each exists.

F. Find Time/Repetition — If the model samples repeatedly, explain as "measured many times and added up over time."

G. Find What Breaks Without Each Piece — For each major component, ask: what goes wrong if we remove this? This reveals WHY it exists.

Output Structure

Write these sections in order:

1. What This Produces

One sentence: what the final output represents in real life.

2. What Controls It

List the real-world factors that push the result up or down. No symbols.

3. Reverse Walkthrough (End → Beginning)

Start from the final result. Walk backwards through each layer until reaching raw inputs. Each step should answer: "where does THIS come from?"

Read the full file on GitHub · 98 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 · 98 lines · 55 tokens per session scan A 8c8dfdd7fed0

Subscribe to this mod's changes

explain is a skill published in the GitHub repository kv0906/pm-kit (133 stars, last pushed 2mo ago), licensed MIT. It adds 55 tokens to every session and 838 once invoked, about $0.0003 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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