explain-back

explain-back is a skill for Claude Code, Codex from JoshuaOliphant/claude-plugins. It costs 117 tokens per session (1,127 once invoked), scanned A, original, no licence file.

A guided learning skill for checking whether you truly understand information, rather than only recognising familiar explanations.

In plain words
What is it for?
It is for processing what you learned, testing your understanding, answering quizzes, and checking whether you can explain a topic before writing about it.
Why use it?
It helps uncover gaps in your understanding and the false confidence that can come from thinking something is clear.

Skill for Claude CodeCodex

Part of the understand plugin — 1 skill shipped together

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/joshuaoliphant/claude-plugins/explain-back
Any agent
npx skills add JoshuaOliphant/claude-plugins --skill explain-back
Clone the repo
git clone --depth 1 https://github.com/JoshuaOliphant/claude-plugins

Made for: Claude Code, Codex.

Or install understand, the plugin that ships this one along with the rest of its 1 skill.

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 explain-back

README.md
[![agentmods](https://agentmods.dev/badge/skills/joshuaoliphant/claude-plugins/explain-back.svg)](https://agentmods.dev/skills/joshuaoliphant/claude-plugins/explain-back)
Your own site
<a href="https://agentmods.dev/skills/joshuaoliphant/claude-plugins/explain-back"><img src="https://agentmods.dev/badge/skills/joshuaoliphant/claude-plugins/explain-back.svg" alt="Measured on agentmods" height="20"></a>
Per session 117 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,127 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00117 $0.01127
Opus 5 $0.00059 $0.00563
Sonnet 5 $0.00023 $0.00225
Haiku 4.5 $0.00012 $0.00113

Measured 4d ago against content hash 1897c17c5e7a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

explain-back 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 4d 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.

plugins/understand/skills/explain-back/SKILL.md · 89 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

3 files 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. 4d ago First seen · 89 lines · 117 tokens per session scan A 1897c17c5e7a

Subscribe to this mod's changes

explain-back is a skill published in the GitHub repository JoshuaOliphant/claude-plugins (6 stars, last pushed yesterday), with no licence file. It adds 117 tokens to every session and 1,127 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 2026-08-31.

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