Fact Check

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name: Fact Check description: This skill should be used when the user asks to "verify claims", "fact check", "validate documentation", "check sources", or needs verification of external source references. Provides patterns for systematic fact verification using Context7 and WebSearch.

<error_escalation> Claim cannot be verified due to missing documentation Note in report as unverifiable, proceed Conflicting information from different sources Document discrepancy, use AskUserQuestion for clarification Claim directly contradicts authoritative source STOP, flag discrepancy to user with evidence Security-related claim is incorrect BLOCK operation, require explicit user acknowledgment </error_escalation>

Version-specific example: Claim: "React 18 introduces automatic batching for all updates" Verification: Query Context7 with topic="batching" for React 18 docs Result: Confirmed - React 18 automatically batches state updates inside promises, setTimeout, and native event handlers

Threshold: Flag claims with confidence below 80

Web standards: WebSearch with domain filters MDN Web Docs: developer.mozilla.org W3C: w3.org WHATWG: html.spec.whatwg.org OWASP: owasp.org

<best_practices> Use Context7 as primary source for library documentation claims Flag all claims with verification confidence below 80 Document evidence source for each verification Prefer libraries with Context7 trust score 7+ for verification Use WebSearch fallback when Context7 unavailable Include direct quotes from sources as evidence Note when verification source has version mismatch </best_practices>

<anti_patterns> Marking claims as verified without actual source check Always query Context7 or WebSearch for evidence before marking verified

<related_agents> Primary agent using this skill for verification Uses fact-check for documentation accuracy Uses fact-check to verify documentation claims </related_agents>

<related_skills> Core tool for library documentation verification Evidence collection methodology Documentation accuracy standards </related_skills>