blog-factcheck
Verify statistics and claims in blog posts by fetching cited source URLs and checking if the claimed data actually appears on the page. Extracts all statistical claims (numbers, percentages, named sources), fetches each cited URL via WebFetch, and scores match confidence (exact match 1.0, paraphrase 0.7-0.9, not found 0.0). Flags uncited claims as UNVERIFIED. Use when user says "fact check", "verify statistics", "check sources", "validate claims", "factcheck", "source verification".
npx skills add Infrasity-Labs/dev-gtm-claude-skills --skill blog-factcheck --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.
# Blog Fact-Check Verify statistics, claims, and source attributions in blog posts. Pure Claude pipeline with no external NLP dependencies. ## Workflow ### Step 1: Read the Blog Post Read the target file and identify all sections containing data claims. ### Step 2: Extract Statistical Claims Scan the full text for every claim that includes a number, percentage, dollar amount, or named source. Build a claims list with these fields: | Field | Description | |-------|-------------| | claim_text | The exact sentence or phrase containing the statistic | | value | The numeric value (e.g., "42%", "$1.2M", "3x") | | attribution | Named source if present (e.g., "HubSpot", "Gartner 2025") | | url | Cited URL if present (from markdown link or parenthetical) | | location | Heading or line number where the claim appears | ### Step 3: Verify Cited Claims For each claim that includes a URL: 1. Fetch the source page via WebFetch 2. Search the returned content for the specific numeric value 3. If exact value found, check surrounding context matches the claim topic 4. Assign a confidence score (see Verification Scoring below) Process claims sequentially to avoid rate-limiting source sites. ### Step 4
- Workflow
- Step 1: Read the Blog Post
- Step 2: Extract Statistical Claims
- Step 3: Verify Cited Claims
- Step 4: Flag Uncited Claims
- Step 5: Generate Verification Report
- Claim Extraction Patterns
- Verification Scoring
- Output Format
- Verification Report: [Post Title]
- Recommended Actions
- Integration
- Cross-reference
- Limitations
What does the blog-factcheck skill do?
Verify statistics and claims in blog posts by fetching cited source URLs and checking if the claimed data actually appears on the page. Extracts all statistical claims (numbers, percentages, named sources), fetches each cited URL via WebFetch, and scores match confidence (exact match 1.0, paraphrase 0.7-0.9, not found 0.0). Flags uncited claims as UNVERIFIED. Use when user says "fact check", "verify statistics", "check sources", "validate claims", "factcheck", "source verification".
How do I install it?
Run `npx skills add Infrasity-Labs/dev-gtm-claude-skills --skill blog-factcheck --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 Infrasity-Labs/dev-gtm-claude-skills, a repository with 97 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.