doublecheck SKILL.md skillA

doublecheck from marielynneblock/arcanum-artifex is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned
mdr add marielynneblock/arcanum-artifex/doublecheck@git:20260710.0115f49

Pins git:20260710.0115f49 in mdr.lock. Pin the fingerprint instead.

Audit grade
A, 17 of 17 checks passed
Kind
SKILL.md skill
Repository
marielynneblock/arcanum-artifex
Path
skills/development/code-review/doublecheck/SKILL.md
Versions recorded
4
Latest version
git:20260710.0115f49, committed Jul 10, 2026
First version recorded
May 10, 2026
Size
15,937 bytes
Repository stars
4
License
none declared

Three-layer verification pipeline for AI output. Extracts verifiable claims, finds supporting or contradicting sources via web search, runs adversarial review for hallucination patterns, and produces a structured verification report with source links for human review.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Doublecheck

Run a three-layer verification pipeline on AI-generated output. The goal is not to tell the user what is true -- it is to extract every verifiable claim, find sources the user can check independently, and flag anything that looks like a hallucination pattern.

## Activation

Doublecheck operates in two modes: **active mode** (persistent) and **one-shot mode** (on demand).

### Active Mode

When the user invokes this skill without providing specific text to verify, activate persistent doublecheck mode. Respond with:

> **Doublecheck is now active.** I'll verify factual claims in my responses before presenting them. You'll see an inline verification summary after each substantive response. Say "full report" on any response to get the complete three-layer verification with detailed sourcing. Turn it off anytime by saying "turn off doublecheck."

Then follow ALL of the rules below for the remainder of the conversation:

**Rule: Classify every response before sending it.**

Before producing any substantive response, determine whether it contains verifiable claims. Classify the response:

| Response type | Contains verifiable claims? | Action |
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint
mdr add marielynneblock/arcanum-artifex/doublecheck@sha256:64fc10ded88bf7f8

The line at the top of this page pins the label git:20260710.0115f49, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_a4kceltx3ujoisfv.svg)](https://markdownregistry.com/a/art_a4kceltx3ujoisfv)

4 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 4 versions of this file, between May 10, 2026 and Jul 10, 2026, about one every 20 days.

versioncommittedcommitsizeaudit
git:20260710.0115f49 latest2026-07-10 0115f49 15,937 BA view · diff
git:20260710.ffb34002026-07-10 ffb3400 15,937 BA view · diff
git:20260515.b861afb2026-05-15 b861afb 15,937 BA view · diff
git:20260510.f26bcec2026-05-10 f26bcec 15,891 BA view

Audit of the latest version

A  17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (15937 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

marielynneblock/arcanum-artifex · 4 stars · license none declared · pushed 2026-09-19 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_a4kceltx3ujoisfv
GET https://markdownregistry.com/api/v1/resolve?ref=marielynneblock/arcanum-artifex/doublecheck
GET https://markdownregistry.com/api/v1/blob/64fc10ded88bf7f8904803bdfa6b4796687e2cdc7fe4d15fd205a1ac4f1380ad

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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Every file in marielynneblock/arcanum-artifex

Other files named doublecheck

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