fact-checking-explainers

A checking process for verifying that every factual claim in an explainer is supported by a real source. An explainer is a piece that makes a difficult topic easier to understand.

In plain words
What is it for?
Use it while researching or after drafting explainers to check claims against cited sources. For code-related claims, it checks the actual implementation.
Why use it?
It prevents unsupported or incorrect statements from reaching readers. Claims must be backed by evidence, corrected to match the source, or removed.

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/analyticalmonk/explain-this/fact-checking-explainers
Any agent
npx skills add analyticalmonk/explain-this --skill fact-checking-explainers
Clone the repo
git clone --depth 1 https://github.com/analyticalmonk/explain-this

Made for: Claude Code, Codex.

Per session 84 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,609 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 $0.00084 $0.01609
Opus 5 $0.00042 $0.00805
Sonnet 5 $0.00017 $0.00322
Haiku 4.5 $0.00008 $0.00161

Measured 2d ago against content hash a660efc471ba, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fact-checking-explainers 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.

skills/fact-checking-explainers/SKILL.md · 121 lines

How it starts

The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fact-Checking Explainers

Overview

An explainer's authority comes from being right. A reader who catches one confident, wrong claim stops trusting the rest of the piece, figures and all. This skill makes claim verification enforceable by tying every checkable claim to evidence you can point to, correcting it, or cutting it. It is not a proofreading pass and not advisory: it is the gate an explainer passes before it is delivered.

The Iron Law

NO EXPLAINER SHIPS WITH AN UNVERIFIED FACTUAL CLAIM.

Every checkable claim either traces to a source that supports it, gets corrected to match the source, or gets cut.

Apply the same resolution loop to every factual claim:

  • Support it with an actual source passage you can point to.
  • Correct it until it matches the source.
  • Cut it when no source supports it.

Treat memory, plausibility, background knowledge, and deadline pressure as signals to run the loop, not reasons to skip it. "Verify" means checking an actual source in this session.

When to Use

Run this skill:

  • At research-time, over the sources gathered for an explainer, before any drafting.
  • Post-draft, over the finished article, before delivery. This is a blocking gate.
  • On request, whenever asked to fact-check, verify, or audit an explainer or article.

creating-explainers and explaining-codebases both call this skill at the gates above. When they do, interactive explainer delivery waits for a PASS report.

When NOT to use: content that is not an explainer, or a pure opinion or editorial piece that makes no factual claims. (Most explainers make many factual claims. Default to running it.)

What Counts as a Checkable Claim

A checkable claim is a specific factual or empirical assertion:

  • numbers, dates, measurements, percentages
  • names, attributions, who-did-what, who-built-what
  • direct quotes
  • historical events and their order
  • performance results and benchmarks
  • mechanism claims: "X uses Y", "X causes Y", "X is faster than Y because Z"

Read the full file on GitHub · 121 lines

Files

What ships with it

2 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. 2d ago First seen · 121 lines · 84 tokens per session scan A a660efc471ba

Subscribe to this mod's changes

fact-checking-explainers is a skill published in the GitHub repository analyticalmonk/explain-this (19 stars, last pushed 1mo ago), licensed MIT. It adds 84 tokens to every session and 1,609 once invoked, about $0.0004 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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