{"uid":"cap_RRwQiIedW32piSZe4cYhx","slug":"verity-suite-faithfulness-checker-bb23816e","name":"Verity Suite Faithfulness Checker","description":"The trust fabric for AI agents — calibrated, fail-closed services agents pay per call.","url":"https://verity-suite.onrender.com/faithful/quick","method":"POST","headers":{},"bodySchema":{"type":"object","required":["source","candidate"],"properties":{"mode":{"type":"string","description":"'summary' or 'translation'. If absent, the checker applies the stricter union of both checks rather than guessing a mode."},"source":{"type":"string","description":"the original source text; the sole ground truth the candidate is judged against"},"candidate":{"type":"string","description":"the summary or translation to check against the source"}}},"responseSchema":{"type":"object","title":"faithful_out","required":["verdict","faithfulness","reasons"],"properties":{"reasons":{"type":"array","items":{"type":"string"},"title":"Reasons","description":"concrete claim-level reasons, each either citing a specific source-vs-candidate discrepancy or confirming specific support; at least one reason required"},"verdict":{"enum":["faithful","minor_drift","unfaithful","uncertain"],"type":"string","title":"Verdict","description":"faithful=every candidate claim is supported by the source and no material source claim is dropped or distorted; minor_drift=only small non-material omissions/nuance loss that change no core claim, entity, quantity, date, or stance; unfaithful=at least one hallucination, contradiction, negation flip, wrong/invented entity-number-date, dropped material claim, or distortion; uncertain=cannot reliably compare (empty/unreadable/truncated/gibberish input or texts too misaligned to map). FAIL CLOSED: never faithful or minor_drift when unsure."},"omissions":{"type":"array","items":{"type":"string"},"title":"Omissions","description":"material claims present in the source but dropped or weakened in the candidate"},"faithfulness":{"type":"number","title":"Faithfulness","maximum":1,"minimum":0,"description":"calibrated probability the candidate fully preserves source meaning with no hallucination, contradiction, or material distortion; 1=certainly faithful, 0=certainly unfaithful. A single confirmed defect drives this well below 0.5."},"hallucinations":{"type":"array","items":{"type":"string"},"title":"Hallucinations","description":"claims asserted in the candidate that are not supported by the source (added or invented content)"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_Klx7pSYFB2bpS_VSxjm5G","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether a summary or translation faithfully preserves the source text, returning a calibrated verdict and claim-level reasons.","exampleAgentPrompt":"Check whether this summary is faithful to the original article — here's the source: 'The Federal Reserve raised interest rates by 0.5% citing persistent inflation concerns.' And here's the candidate summary: 'The Federal Reserve cut rates by 0.5% due to inflation.' Flag any hallucinations or distortions.","exampleUseCases":null,"resultDescription":"Returns a verdict enum (faithful, minor_drift, unfaithful, or uncertain), a calibrated faithfulness probability score between 0 and 1, an array of claim-level reasons citing specific source-vs-candidate discrepancies or confirmations, a list of hallucinations (claims in the candidate not supported by the source), and a list of material omissions (claims in the source dropped or weakened in the candidate).","failureModes":["Empty or unreadable source or candidate text returns verdict 'uncertain' rather than a guess","Completely misaligned texts (e.g. different languages without mode set) may return 'uncertain'","Truncated or gibberish input returns 'uncertain' — endpoint fails closed, never guesses faithful","Missing required fields (source or candidate) returns a 400-level error","Very long texts may hit token or processing limits causing a timeout or truncation-related 'uncertain'"],"whenToPreferThis":"Use this endpoint when you need a calibrated, fail-closed faithfulness verdict on a summary or translation — not just a similarity score. Prefer it over embedding cosine similarity when you need claim-level hallucination and omission detection. Prefer it over general-purpose LLM prompting when you need a structured, reliable verdict with explicit reasons rather than a freeform answer. Best suited for pipelines that need to gate on faithfulness before publishing or acting on AI-generated content.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:52:46.568Z","isFirstParty":false}