{"uid":"cap_Y8FWntG0UZySo0O0F90Su","slug":"truthpal-claim-verification-200269ae","name":"TruthPal Claim Verification","description":"TruthPal: source-grounded claim verification for AI agents. Supported, contradicted or uncertain verdicts with exact source evidence. $0.02 USDC per request via x402 on Base.","url":"https://api.thetruthpal.com/v1/verify?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"claim":{"type":"string","maxLength":2000,"minLength":5,"description":"The factual claim to evaluate. Leading and trailing whitespace is trimmed before validation."},"source_url":{"type":"string","format":"uri","pattern":"^[Hh][Tt][Tt][Pp][Ss]?://","maxLength":2048,"description":"The credential-free public HTTP or HTTPS source containing the evidence to evaluate."}}},"responseSchema":{"type":"json","example":{"verdict":"supported","evidence":["The source states that the Moon formed about 4.5 billion years ago."],"reasoning":"The source directly supports the claim that the Moon formed several billion years ago.","confidence":0.94,"source_freshness":"current","supporting_evidence":["The source states that the Moon formed about 4.5 billion years ago."],"contradicting_evidence":[]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","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_cFuxW693S9tls4QtqzYMF","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Evaluates a factual claim against a provided source URL and returns a structured verdict with confidence score, reasoning, and supporting/contradicting evidence","exampleAgentPrompt":"Can you fact-check this claim — 'The Moon is approximately 4.5 billion years old' — against this NASA article: https://moon.nasa.gov/moon-in-motion/overview/ and tell me if the source actually supports it?","exampleUseCases":[{"title":"AI output grounding check","prompt":"I just got this answer from an AI: 'The global average temperature has risen by 1.1 degrees Celsius since pre-industrial times.' Can you verify that claim against this IPCC report page — https://www.ipcc.ch/report/ar6/wg1/chapter/summary-for-policymakers/ — and tell me how confident you are that the source backs it up?"},{"title":"News article claim verification","prompt":"A news article says 'Inflation in the US hit 9.1% in June 2022, the highest in 40 years.' Can you check that claim against https://www.bls.gov/cpi/ and give me a verdict with the supporting evidence from the page?"},{"title":"Research citation validation","prompt":"I need to cite a study in my report — I'm claiming 'regular exercise reduces the risk of heart disease by 35%'. Can you verify that against https://www.heart.org/en/healthy-living/fitness/fitness-basics/why-is-physical-activity-so-important and tell me if the source actually says that?"}],"resultDescription":"A JSON object containing: a verdict string (e.g. 'true', 'false', 'uncertain'), a natural-language reasoning explanation, a confidence score between 0 and 1, a source_freshness indicator, an array of supporting_evidence quotes from the source, and an array of contradicting_evidence quotes from the source","failureModes":["Source URL is inaccessible, behind a paywall, or returns a non-200 response — verdict cannot be generated","Claim is too vague or ambiguous for the system to evaluate against the source","Source content is not in a machine-readable format (e.g. PDF, behind JavaScript rendering)","Claim is entirely outside the scope of the source content, resulting in an 'uncertain' verdict with low confidence","Malformed input — missing claim or source_url fields returns a validation error"],"whenToPreferThis":"Choose TruthPal when you need a structured, evidence-backed verdict on a specific factual claim tied to a particular source URL — especially when validating AI-generated content, citations, or news claims. Prefer this over generic search or web-scraping when you need not just a yes/no but also a confidence score, extracted supporting quotes, and explicit reasoning. Best when both a claim and a verifiable public source are already known.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-10T06:33:49.177Z","isFirstParty":false,"canonicalSlug":"truthpal-claim-verification-200269ae"}