Fact Checker & Claim Verifier

# Fact Checker & Claim Verifier

Verify claims, statistics, and quotes by cross-referencing multiple sources. Rate accuracy and flag misinformation.

## When to Use

- "Is it true that {claim}?"
- "Fact-check this article for me"
- "Verify these statistics before I use them in my presentation"

## Requirements

- **Brave Search MCP** for multi-source verification

## Workflow

### Step 1 — Identify Claims

From user input, extract specific verifiable claims:
- Factual assertions ("X is Y")
- Statistics ("N% of people...")
- Quotes ("Person X said...")
- Historical claims ("In year X, event Y happened")

### Step 2 — Research Each Claim

For each claim, search multiple sources:

```
brave_web_search: "{EXACT_CLAIM}"
brave_web_search: "{CLAIM_KEYWORDS} fact check"
brave_web_search: "{STATISTIC} source original study"
brave_web_search: "{QUOTE} original context {PERSON}"
```

Look for:
- Original source of the claim
- Corroborating sources
- Contradicting sources
- Established fact-check articles

### Step 3 — Rate Each Claim

```markdown
# Fact Check Report
📅 Checked: {DATE}

## Claim 1: "{CLAIM_TEXT}"

**Verdict:** ✅ True / 🟡 Mostly True / ⚠️ Misleading / ❌ False / ❓ Unverifiable

**Evidence:**
- Source 1: [{Publication}]({URL}) — {supports/contradicts} — "{key quote}"
- Source 2: [{Publication}]({URL}) — {supports/contradicts} — "{key quote}"
- Source 3: [{Publication}]({URL}) — {supports/contradicts}

**Context:** {Important nuance the claim leaves out}

**Original source:** {Where this claim originated, if findable}

---

## Claim 2: "{CLAIM_TEXT}"

**Verdict:** {rating}
...

---

## Summary
| # | Claim | Verdict | Sources |
|---|-------|---------|---------|
| 1 | {Short claim} | ✅/🟡/⚠️/❌/❓ | {N} sources |
| 2 | {Short claim} | {verdict} | {N} sources |

## Methodology
- Claims verified against {N} independent sources
- Verdicts require 2+ corroborating sources for "True"
- "Misleading" = technically true but missing critical context
- "Unverifiable" = insufficient evidence to confirm or deny
```

### Step 4 — Save Report

```bash
mkdir -p outputs/research
cat > "outputs/research/fact-check-{DATE}.md" << 'EOF'
{FACT_CHECK_REPORT}
EOF
```

## Important Rules

- Never rate a claim without searching for evidence first
- Require 2+ independent sources to rate "True"
- Always provide the original source when findable
- "Misleading" is distinct from "False" — context matters
- Acknowledge when claims are genuinely uncertain or debated
- Avoid political bias — verify from diverse sources

## Example Prompts

- "Is it true that humans only use 10% of their brain?"
- "Fact-check these statistics before I put them in my report"
- "Verify the claims in this article: [paste text]"