takeokunn/Fact Check

<purpose> Provide patterns and methodology for systematic fact-checking of claims against authoritative external sources. This skill contains the knowledge (patterns, concepts, best practices) for verification operations. </purpose> <tools> <tool name="resolve-library-id"> <description>Resolve package name to Context7-compatible library ID</description> <param name="libraryName">Library name to search for</param> <use_case>Must call before get-library-docs for library documentation claims</use_case> </tool> <tool name="get-library-docs"> <description>Fetch documentation for a specific library to verify claims</description> <param name="context7CompatibleLibraryID">Library ID from resolve-library-id</param> <param name="topic">Specific topic to verify</param> <param name="tokens">Max tokens to retrieve (default: 5000)</param> <use_case>Verify claims about library APIs, behavior, and best practices</use_case> </tool> <tool name="WebSearch"> <description>Search web for verification of general claims</description> <param name="query">Search query for verification</param> <use_case>Verify claims about standards, specifications, and general technical facts</use_case> </tool> <tool name="WebFetch"> <description>Fetch specific URL content for verification</description> <param name="url">URL to fetch</param> <param name="prompt">Extraction prompt for relevant content</param> <use_case>Verify claims against specific documentation pages or specifications</use_case> </tool> </tools> <patterns> <pattern name="claim_extraction"> <description>Identify claims that reference external sources for verification</description> <decision_tree name="when_to_use"> <question>Does the content reference external documentation or standards?</question> <if_yes>Apply claim extraction to identify verifiable assertions</if_yes> <if_no>No fact-checking needed for this content</if_no> </decision_tree> <example> Claim types to extract: Library API claims: "useState returns a tuple" Documentation references: "according to the React docs" Standard compliance: "follows WCAG 2.1 AA" Version-specific behavior: "in React 18, Suspense..." Performance claims: "O(log n) complexity per MDN"

  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
</example>

</pattern> <pattern name="source_selection"> <description>Choose appropriate verification source based on claim type</description> <decision_tree name="when_to_use"> <question>What type of claim needs verification?</question> <branch condition="Library/framework API">Use Context7 with resolve-library-id then get-library-docs</branch> <branch condition="Web standard/specification">Use WebSearch for official specification</branch> <branch condition="General technical fact">Use WebSearch with authoritative domain filter</branch> <branch condition="Specific documentation URL">Use WebFetch to retrieve and verify</branch> </decision_tree> <example> Source priority: Context7 for library documentation (trust score 7+) WebFetch for specific URLs cited in claims WebSearch for general technical claims Mark as unverifiable if no source available </example> </pattern> <pattern name="confidence_assessment"> <description>Calculate verification confidence based on evidence quality</description> <decision_tree name="when_to_use"> <question>Has verification evidence been collected?</question> <if_yes>Apply confidence assessment to rate verification quality</if_yes> <if_no>Continue evidence collection before assessment</if_no> </decision_tree> <example> Confidence levels: 90-100: Exact match with authoritative source 80-89: Strong match with minor wording differences 70-79: Partial match, some details unverified 60-69: Weak match, significant uncertainty 0-59: No match or contradictory evidence

  Threshold: Flag claims with confidence below 80
</example>

</pattern> <pattern name="discrepancy_reporting"> <description>Format and report verification failures with evidence</description> <decision_tree name="when_to_use"> <question>Is the verification confidence below 80?</question> <if_yes>Apply discrepancy reporting to document the issue</if_yes> <if_no>Mark claim as verified</if_no> </decision_tree> <example> Discrepancy report format: Claim: Original assertion made Source: Where claim was made Verification source: Context7/WebSearch result Evidence: Actual information from source Confidence: 0-100 score Recommendation: Suggested correction or note </example> </pattern> </patterns> <concepts> <concept name="verification_sources"> <description>Authoritative sources for different claim types</description> <example> Library documentation: Context7 MCP React: /facebook/react Next.js: /vercel/next.js TypeScript: /microsoft/typescript NixOS: /nixos/nixpkgs

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

</concept> <concept name="claim_types"> <description>Categories of verifiable claims</description> <example> API behavior: Function signatures, return types, parameters Configuration: Config options, default values, valid settings Best practices: Recommended patterns from official docs Deprecation: API deprecation status and alternatives Compatibility: Version compatibility and requirements Performance: Complexity claims, benchmark references Security: Security recommendations and vulnerability info </example> </concept> <concept name="confidence_thresholds"> <description>Confidence score interpretation</description> <example> 80+: Verified - Claim matches authoritative source 60-79: Uncertain - Partial verification, review recommended Below 60: Disputed - Claim contradicts or unsupported by source Unverifiable: No authoritative source available </example> </concept> </concepts>

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

<anti_patterns> <avoid name="assumption_verification"> <description>Marking claims as verified without actual source check</description> <instead>Always query Context7 or WebSearch for evidence before marking verified</instead> </avoid>

<avoid name="single_source_reliance"> <description>Relying on only one source for disputed claims</description> <instead>Cross-reference with multiple sources when confidence is borderline (70-85)</instead> </avoid> <avoid name="ignoring_version_context"> <description>Verifying claims without considering version differences</description> <instead>Note version context and verify against appropriate documentation version</instead> </avoid> <avoid name="over_verification"> <description>Attempting to verify every statement including obvious facts</description> <instead>Focus on claims referencing external sources, APIs, and specifications</instead> </avoid> </anti_patterns> <rules priority="critical"> <rule>Always verify claims against authoritative sources before flagging</rule> <rule>Use Context7 as primary source for library and framework claims</rule> <rule>Flag claims with confidence below 80 in fact check results</rule> <rule>Document evidence source for every verification</rule> </rules> <rules priority="standard"> <rule>Use WebSearch as fallback when Context7 unavailable</rule> <rule>Prefer official documentation over third-party sources</rule> <rule>Note version context when verifying version-specific claims</rule> <rule>Cross-reference disputed claims with multiple sources</rule> </rules>

<error_escalation inherits="core-patterns#error_escalation"> <examples> <example severity="low">Claim cannot be verified due to missing documentation</example> <example severity="medium">Conflicting information from different sources</example> <example severity="high">Claim directly contradicts authoritative source</example> <example severity="critical">Security-related claim is incorrect</example> </examples> </error_escalation>

<constraints> <must>Query authoritative sources before verification</must> <must>Document evidence for all verification results</must> <must>Flag discrepancies with confidence scores</must> <avoid>Marking claims verified without source check</avoid> <avoid>Verifying claims based on assumption or memory</avoid> <avoid>Ignoring version context in verification</avoid> </constraints>

<related_skills> <skill name="context7-usage">Core tool for library documentation verification</skill> <skill name="investigation-patterns">Evidence collection methodology</skill> <skill name="technical-documentation">Documentation accuracy standards</skill> </related_skills>

<related_agents> <agent name="explore">Locate referenced code patterns and claims in the codebase</agent> <agent name="quality-assurance">Verify factual accuracy of implementation assertions</agent> </related_agents>