doublecheck
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.
npx skills add majiayu000/claude-skill-registry --skill doublecheck --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# 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 | |--------------|----------------------
- Activation
- Active Mode
- One-Shot Mode
- Deactivation
- Layer 1: Self-Audit
- Step 1: Extract Claims
- Step 2: Check Internal Consistency
- Step 3: Initial Confidence Assessment
- Layer 2: Source Verification
- Search Strategy
- What Counts as a Source
- Handling Citations Specifically
- Layer 3: Adversarial Review
- Hallucination Pattern Checklist
What does the doublecheck skill do?
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.
How do I install it?
Run `npx skills add majiayu000/claude-skill-registry --skill doublecheck --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From majiayu000/claude-skill-registry, a repository with 534 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.