fact-check

fact-check is a command for Claude Code from runnithan/claudex-setup. It costs 22 tokens per session (169 once invoked), scanned A, original, MIT.

A command for checking factual claims in written content against information found in authoritative online sources.

In plain words
What is it for?
Use it to verify each claim, record its status and source, and summarize which claims need changes.
Why use it?
It separates supported claims from unsupported or incorrect ones, making errors easier to correct before publishing.

Command for Claude Code

Part of the claudex-setup plugin — 3 skills, 21 commands, 22 agents 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 commands/runnithan/claudex-setup/fact-check
Clone the repo
git clone --depth 1 https://github.com/runnithan/claudex-setup

Made for: Claude Code.

Or install claudex-setup, the plugin that ships this one along with the rest of its 3 skills, 21 commands, 22 agents.

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 fact-check

README.md
[![agentmods](https://agentmods.dev/badge/commands/runnithan/claudex-setup/fact-check.svg)](https://agentmods.dev/commands/runnithan/claudex-setup/fact-check)
Your own site
<a href="https://agentmods.dev/commands/runnithan/claudex-setup/fact-check"><img src="https://agentmods.dev/badge/commands/runnithan/claudex-setup/fact-check.svg" alt="Measured on agentmods" height="20"></a>
Per session 22 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 169 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 $0.00022 $0.00169
Opus 5 $0.00011 $0.00084
Sonnet 5 $0.00004 $0.00034
Haiku 4.5 $0.00002 $0.00017

Measured 4d ago against content hash 81ce8bf839a9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fact-check 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.

.claude/commands/fact-check.md · 24 lines

What it actually says

Review the following content and fact-check every factual claim:

$ARGUMENTS

For each claim:

  1. Identify the specific factual assertion
  2. Search the web for verification using authoritative sources
  3. Classify as Verified, Unverified, or Incorrect

Output a markdown table:

# Claim Status Source / Notes
1 ... Verified / Unverified / Incorrect Link or explanation

After the table, provide a summary: X/Y claims verified, any corrections needed.

If no arguments are provided, ask the user to paste or describe the content they want fact-checked.

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 · 24 lines · 22 tokens per session scan A 81ce8bf839a9

Subscribe to this mod's changes

fact-check is a command published in the GitHub repository runnithan/claudex-setup (1 stars, last pushed 3d ago), licensed MIT. It adds 22 tokens to every session and 169 once invoked, about $0.0001 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.