{"uid":"cap_xQ-eB5I_BTBvqQX0eO7Rw","slug":"halowerk-grounding-score-26ad65ae","name":"Halowerk Grounding Score","description":"Splits the answer into sentences and measures, for each one, how much of it is covered by the supplied sources. Coverage is asymmetric on purpose: the question is what share of the statement appears in the source, so a long source can fully cover a short claim, and it combines single-word overlap with word-pair overlap because the same words in a different order can mean something else. Two checks override coverage and this is the point of the endpoint.","url":"https://research.halowerk.com/v1/grounding-score","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"answer":{"type":"string","maxLength":40000,"minLength":10,"description":"The answer or text to be checked against the sources."},"sources":{"type":"array","items":{"type":"object","required":["text"],"properties":{"id":{"type":"string","maxLength":100,"description":"Optional identifier, echoed back on every match."},"url":{"type":"string","maxLength":2000,"description":"Optional origin, passed through unchanged."},"text":{"type":"string","maxLength":200000,"minLength":1,"description":"Full text of the source."}},"additionalProperties":false},"maxItems":50,"minItems":1,"description":"The sources the answer is supposed to rest on."},"min_coverage":{"type":"number","default":0.6,"maximum":1,"minimum":0.1,"description":"Coverage from which a sentence counts as supported. Default 0.6."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_SXjYDnVOIax6v2Vhe-U0j","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Scores how well a set of source documents supports each sentence in an answer, detecting hallucinations and unsupported claims via coverage and override checks.","exampleAgentPrompt":"Can you check how well this AI-generated answer is grounded in the sources I retrieved? Score each sentence for how much of it is actually covered by the source documents, and flag any sentences that aren't supported.","exampleUseCases":[{"title":"RAG faithfulness check","prompt":"I have a 5-sentence answer my RAG pipeline generated and 3 source chunks it retrieved. Can you score each sentence for how much of it is actually covered by those sources so I can catch any hallucinated claims?"},{"title":"Research summary verification","prompt":"I wrote a summary of a scientific topic based on three papers. Can you check each sentence of my summary against those papers and tell me which sentences are fully covered, partially covered, or not covered at all?"},{"title":"Chatbot quality assurance","prompt":"Before publishing this customer-facing chatbot response, I need to verify it's grounded in our official documentation. Score each sentence of the response against the relevant docs and flag anything that isn't supported."}],"resultDescription":"Returns a per-sentence breakdown of grounding coverage scores indicating what share of each statement appears in the provided sources, combining single-word and word-pair overlap metrics, plus override flags that can supersede coverage scores when specific conditions are met.","failureModes":["missing or empty answer text returns an error","no source documents provided results in zero coverage scores","very short single-word sources may produce unreliable overlap metrics","override conditions may suppress coverage scores unexpectedly if not understood","large inputs with many long documents may exceed payload limits"],"whenToPreferThis":"Choose this endpoint when you need fine-grained, sentence-level grounding verification of AI-generated text against source documents — especially for RAG pipelines, hallucination detection, or research quality assurance. Unlike simple string matching, it uses asymmetric coverage (a long source can cover a short claim) and combines unigram and bigram overlap to account for word-order sensitivity. Prefer it over generic similarity metrics when you need both a nuanced coverage score and the ability to override coverage with hard rule checks.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:37:23.731Z","isFirstParty":false}