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@swayson
Created October 26, 2025 07:31
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  1. swayson created this gist Oct 26, 2025.
    241 changes: 241 additions & 0 deletions fact-check.md
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    # Fact Check

    Verify claims and statements from websites, papers, or text by cross-referencing multiple sources.

    ## Workflow

    ### 1. Gather Input

    **Determine input type:**
    - URL provided: `/fact-check https://example.com/article`
    - Text provided: `/fact-check "specific claim to verify"`
    - No input: Prompt user for content to fact-check

    **If URL provided:**
    ```bash
    # Fetch content from URL
    WebFetch tool with URL
    Extract main claims and assertions
    ```

    **If file path provided:**
    ```bash
    # Read document (supports PDF, MD, TXT)
    Read tool for text files
    Extract claims for verification
    ```

    ### 2. Extract Claims

    **Identify verifiable statements:**
    - Break down content into discrete claims
    - Identify factual assertions vs opinions
    - Note quantitative claims (numbers, dates, statistics)
    - Flag subjective vs objective statements

    **Present claims to user:**
    - List all extracted claims
    - Ask which to verify (all or specific ones)
    - Check if user wants to specify preferred sources

    ### 3. Verify Each Claim

    **For each claim:**

    **Cross-reference search:**
    ```bash
    # Use WebSearch to find supporting/contradicting evidence
    Search for claim + key terms
    Search for contradicting evidence
    Search academic/authoritative sources if applicable
    ```
    **If user specified sources:**
    - Prioritize those sources
    - Still check for contradicting evidence elsewhere
    **Evaluate evidence:**
    - Check source credibility
    - Look for primary vs secondary sources
    - Note publication dates
    - Identify potential bias
    - Find consensus vs outlier positions
    ### 4. Assess Confidence
    **Use probabilistic thinking (Annie Duke method):**
    - **90-100%**: Multiple high-quality primary sources agree, no credible contradictions
    - **70-89%**: Strong evidence from credible sources, minor contradictions explained
    - **50-69%**: Mixed evidence, some credible sources support, some contradict
    - **30-49%**: Weak support, significant contradictions, or low-quality sources
    - **10-29%**: Strong evidence against claim, most sources contradict
    - **0-9%**: Claim definitively false based on high-quality evidence
    **Consider:**
    - Source quality and expertise
    - Recency of information
    - Consensus among experts
    - Base rates and prior probability
    - What we don't know (epistemic humility)
    ### 5. Generate Report
    **Create markdown file: `fact-check-report-{timestamp}.md`**
    **Report structure:**
    ```markdown
    # Fact Check Report
    Generated: {timestamp}
    Source: {URL or "User provided text"}
    ## Summary
    - Total claims verified: X
    - High confidence (70%+): X
    - Medium confidence (30-69%): X
    - Low confidence/False (<30%): X
    ## Detailed Findings
    ### Claim 1: "{claim text}"
    **Verification Status**: ✓ Verified / ⚠ Uncertain / ✗ False / ~ Misleading
    **Confidence**: X% (reasoning)
    **Supporting Evidence**:
    - [Source name](URL) - {excerpt or summary}
    - [Source name](URL) - {excerpt or summary}
    **Contradicting Evidence**:
    - [Source name](URL) - {excerpt or summary}
    **Analysis**:
    {Nuanced explanation of why confidence is at this level}
    **Key Uncertainties**:
    - What we don't know
    - Limitations of available evidence
    ---
    {Repeat for each claim}
    ## Overall Assessment
    {Summary of document/claim credibility}
    ## Sources Consulted
    1. [Source](URL)
    2. [Source](URL)
    ...
    ## Methodology Notes
    - Search terms used
    - Source selection criteria
    - Limitations of this fact-check
    ```

    ### 6. Present Results

    **Show user:**
    - Summary of findings
    - Path to detailed report
    - Offer to investigate specific claims further
    - Ask if user wants to fact-check related claims

    ## Rules

    **Source Quality:**
    - Prioritize primary sources over secondary
    - Academic/peer-reviewed > news > blogs
    - Check source funding/bias
    - Note conflicts of interest
    - Prefer recent sources for time-sensitive claims

    **Epistemic Humility:**
    - Be explicit about uncertainty
    - Don't force binary true/false on complex claims
    - Note when evidence is insufficient
    - Distinguish "no evidence found" from "evidence of absence"
    **Handling Opinions:**
    - Mark subjective statements clearly
    - Don't fact-check opinions as true/false
    - Can verify attributed quotes
    - Can check if opinion is widely held

    **Safety:**
    - Don't fact-check personal/private information
    - Warn if claim requires specialized expertise
    - Note when topic is actively debated
    - Avoid political bias in source selection
    ## Input Arguments
    **URL mode:**
    ```
    /fact-check https://example.com/article
    ```
    **Text mode:**
    ```
    /fact-check "The Earth is 4.5 billion years old"
    ```
    **With source specification:**
    ```
    /fact-check "claim" --sources nature.com,science.org
    ```
    **Interactive mode:**
    ```
    /fact-check
    # Prompts for input
    ```
    ## Usage Examples
    **Example 1 - URL:**
    ```
    /fact-check https://example.com/health-article
    ```
    **Example 2 - Inline claim:**
    ```
    /fact-check "Coffee reduces risk of Alzheimer's by 65%"
    ```
    **Example 3 - Interactive:**
    ```
    /fact-check
    > What would you like me to fact-check?
    [paste article text or URL]
    > Should I verify all claims or specific ones?
    All
    > Any preferred sources?
    None, use your judgment
    ```
    ## Output
    ```
    Analyzing content...
    Extracted 12 verifiable claims
    Verifying claim 1/12: "X happened in 2020"
    - Searching for evidence...
    - Found 5 sources
    - Confidence: 85%
    ...
    Report generated: fact-check-report-20251026-143022.md
    Summary:
    ✓ Verified (70%+): 8 claims
    ⚠ Uncertain (30-69%): 3 claims
    ✗ False/Misleading (<30%): 1 claim
    Would you like me to investigate any claims further?
    ```