| name | output-fact-checker |
| description | Verifies factual claims in agent-generated outputs against source documents and known references. Cross-references stated figures, dates, names, regulatory citations, and statistical claims to identify unsupported assertions, hallucinated data, and misattributed information before outputs reach end users.
|
| version | 1.0.0 |
| author | agentops |
| license | MIT |
| x-agent | {"industries":["cross-industry"],"risk_level":"standard","requires_approval":false,"memory_blocks":[],"mcp_dependencies":[],"tools":["file-read","web-search"],"trigger_keywords":["fact check","verify","accuracy","hallucination","source verification","claims"],"run_after":[],"compatibility":"Agent Platform >= 1.0"} |
Output Fact Checker
Purpose
Validates factual claims present in agent-generated outputs by cross-referencing them against provided source documents, authoritative databases, and publicly available records. The skill systematically identifies numerical discrepancies, incorrect attributions, fabricated citations, and unsupported statistical claims. It produces a structured verification report that flags each claim with a confidence rating and source attribution, enabling human reviewers to focus attention on the highest-risk assertions.
When to Use
- Before publishing or distributing any agent-generated content that contains specific facts, figures, or citations
- When an agent output references legislation, regulations, or legal precedents that must be accurate
- After generating reports containing financial data, performance metrics, or statistical summaries
- When the output includes dates, named individuals, organisational details, or geographic information that could be verified
- As a final quality gate in any workflow where factual accuracy carries reputational or compliance risk
- When combining information from multiple source documents where cross-referencing errors may occur
Instructions
- Receive the agent-generated output text and any source documents or reference materials that were used during generation. Catalogue each source with a unique identifier for traceability.
- Parse the output to extract all discrete factual claims. Categorise each claim by type: numerical (figures, percentages, dates), attributive (names, titles, organisations), referential (citations, regulation numbers, case references), or statistical (trends, comparisons, aggregates).
- For each extracted claim, locate the corresponding passage in the source documents. Record whether the claim is directly supported, partially supported, contradicted, or absent from the provided sources.
- For claims not found in source documents, attempt verification using web search against authoritative sources. Prioritise government databases, official organisational publications, and peer-reviewed materials. Record the verification source URL and retrieval date.
- Assign a confidence rating to each claim: VERIFIED (exact match with source), PARTIALLY VERIFIED (substance correct but details differ), UNVERIFIED (no supporting source found), or CONTRADICTED (source evidence conflicts with the claim).
- For any claim rated UNVERIFIED or CONTRADICTED, draft a specific correction note that identifies the discrepancy and provides the correct information where available.
- Compile the full verification report with a summary table showing total claims checked, verification distribution, and a ranked list of issues by severity.
- Flag any patterns of systematic error, such as consistent misattribution to a single source or repeated numerical inflation, that may indicate a broader generation issue requiring upstream correction.
Output Format
The verification report is structured as follows:
- Summary Header: Total claims extracted, number verified, partially verified, unverified, and contradicted, with an overall accuracy percentage.
- Claims Table: Each row contains the claim text, claim type, source reference, verification status, confidence rating, and correction note if applicable.
- High-Risk Findings: A prioritised list of contradicted or unverified claims with detailed explanations and suggested corrections.
- Source Inventory: A numbered list of all sources consulted during verification, including document titles, URLs, and access timestamps.
- Pattern Analysis: Any identified systematic issues with recommendations for upstream process adjustments.
Quality Checks
- Every factual claim in the output must be individually assessed; no claims should be skipped or batch-approved without examination
- Numerical values must be checked for unit consistency, decimal placement, and order-of-magnitude accuracy
- Regulatory and legal citations must be verified against official legislative databases, not secondary summaries
- Date claims must be validated for chronological consistency within the document as well as factual correctness
- Attribution claims (who said what, who holds which role) must be verified against the most recent available information
- The verification report itself must not introduce new unsupported claims or speculative corrections
Limitations
- Cannot verify claims about private or confidential information that is not present in the provided source documents or publicly available records
- Real-time data verification depends on web search availability and may not reflect information published after the last search index update
- Does not assess the quality of reasoning, logical coherence, or opinion-based statements; only factual claims are within scope
- Cannot guarantee detection of sophisticated fabrications that closely mimic plausible facts without obvious source contradictions
- Verification of claims in languages other than English requires source documents in the corresponding language
- Does not perform plagiarism detection; textual similarity to sources is not assessed beyond factual accuracy