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Fact-Checking AI Hallucinations

Version 2.0 Standard: Premium

AI does not know things. It predicts text. When it predicts confidently, the output looks like a fact. When it predicts a plausible but false fact, the output is a hallucination — and it looks exactly as confident as a true statement. You cannot tell the difference by reading the AI's output. The only defense is a systematic verification process applied to every claim, statistic, and name in every AI draft.


Part 1 — What Hallucinations Look Like

The Hallucination Spectrum

TypeExampleDanger Level
Fabricated statistics"According to a 2024 HubSpot study, 73% of marketers..." (study doesn't exist)🔴 High — readers may cite your fake stat
Invented citations"As noted in Smith et al. (2023)..." (paper doesn't exist)🔴 High — destroys credibility if checked
Outdated information"WordPress powers 43% of the web" (it was true in 2023, not 2025)🟡 Medium — technically wrong, but close
Confident wrong claims"Google's PageRank algorithm was deprecated in 2018" (incorrect)🔴 High — presented with authority
Plausible nonsense"The Flesch-Kincaid readability score measures semantic density" (it doesn't)🟡 Medium — sounds right, is wrong
Fictional products/features"Mailchimp's AI Subject Line Generator" (doesn't exist as described)🟡 Medium — readers discover the lie when they try

Part 2 — The Verification Workflow

The 3-Pass Verification Process

flowchart TD
A[AI Draft Complete] --> B[Pass 1: Flag\nEvery Claim]
B --> C[Pass 2: Verify\nFlagged Claims]
C --> D[Pass 3: Source\nAll Statistics]
D --> E{All Claims\nVerified?}
E -- Yes --> F[Draft Approved\nfor Editing]
E -- No --> G[Remove or Replace\nUnverifiable Claims]
G --> F

style F fill:#217346,color:#fff
style G fill:#F4A261,color:#000

Read the draft and highlight every:

  • Statistic — any percentage, number, or quantified claim
  • Named source — any study, report, person, or organization cited
  • Factual claim — any assertion about how something works
  • Product feature — any specific capability attributed to a tool
  • Date-sensitive fact — any claim that could have changed since the AI's training data

Rule: If it sounds like a fact, flag it. Err on the side of over-flagging.


Part 3 — High-Risk Categories

Some content areas are more prone to hallucination than others. Apply extra scrutiny here.

CategoryRisk LevelCommon HallucinationsVerification Priority
Statistics and data🔴 Very HighFabricated percentages, wrong study yearsAlways verify against primary source
Legal and compliance🔴 Very HighWrong regulations, outdated lawsAlways consult official sources
Medical/health claims🔴 Very HighIncorrect dosages, unsupported health claimsNEVER publish without expert review
Product comparisons🟡 HighWrong pricing, features that don't existCheck each product's official page
Historical facts🟡 MediumConflated timelines, wrong datesCross-reference with 2+ sources
Technical processes🟡 MediumPlausible but incorrect instructionsTest the process yourself if possible

Part 4 — Bad vs. Good Examples

"According to a 2024 study by McKinsey, 87% of B2B buyers prefer to complete their purchase journey digitally without interacting with a sales representative. This represents a 23% increase from 2022. The shift has led companies like Salesforce and HubSpot to invest heavily in self-serve purchasing platforms."

(Why it fails: This stat sounds plausible — McKinsey does publish B2B research. But the specific "87%" and "23% increase" need verification. If you search for this exact study, you may find similar numbers but not this exact claim. The 87% may be a hallucination based on a real 2022 finding of 70%.)


Part 5 — AI Collaboration Guidelines

The "Hallucination Detector" Prompt

Role: Research fact-checker Task: Review this draft and flag every statement that could be a hallucination. For each flagged item:

  1. Quote the exact claim
  2. Rate the hallucination risk: Low / Medium / High
  3. Suggest how to verify it (specific source to check)
  4. If the claim is likely fabricated, suggest a real alternative or recommend deletion Rules: Flag ALL statistics, ALL named studies, ALL product features, and ALL date-specific claims. Input: [Paste Draft]
AI checking AI is not reliable.

Using one AI model to verify another AI model's facts does NOT work. Both models may hallucinate the same plausible-sounding information. The verification step MUST use primary human sources — real websites, real reports, real documentation.


Part 6 — Output Checklist

Before moving to the next lesson, confirm every item below.
  • Hallucination types: You can identify 6 types of AI hallucination.
  • 3-pass process: You flag, verify, and source every claim in every AI draft.
  • Primary sources: Every statistic links to or names its primary source.
  • High-risk awareness: You apply extra scrutiny to statistics, legal claims, and product features.
  • Removal discipline: If you can't verify a claim, you delete it — no exceptions.
  • No AI-on-AI verification: You never use AI to fact-check AI.

Internal use only. Do not distribute externally. For questions or suggested updates, raise with the content lead.