{"name":"grounded-answer-check","description":"Answer a question and grade how well the answer actually holds up against independent sources, in one call. Composite: one call runs answer-web + web-search + wikipedia-search + retrieval-rerank + citation-verify in parallel, then maps the answer's sentences onto reranked, re-verified evidence passages. Pass a question to get a generated, cited answer, or pass your own answer as context to grade it instead. Returns a support score, a supported/unsupported verdict, and the exact spans that had no backing evidence. Use it as a grounded answer API, hallucination check, RAG grounding evaluator, or source-backed QA layer before an agent trusts and repeats an answer.","price":"$0.06","method":"POST","input_schema":{"properties":{"question":{"type":"string","description":"The question to answer or to grade an answer against. Max 500 chars."},"context":{"type":"string","description":"Optional pre-written answer to GRADE instead of generating a new one via answer-web. Max 4000 chars."},"strictness":{"type":"string","enum":["lenient","strict"],"description":"How high the support score must be to mark the answer 'supported'. 'strict' requires stronger evidence coverage. Default 'lenient'."}},"required":["question"]},"input_example":{"question":"What is the capital of France?"},"output_example":{"question":"What is the capital of France?","answer":"Paris is the capital of France. It sits on the Seine river.","generated":true,"grounding":{"supported":true,"unsupported_spans":[],"support_score":1},"evidence":[{"title":"Paris facts","url":"https://example.com/paris","supports":true}],"composed_of":["answer-web","web-search","wikipedia-search","retrieval-rerank","citation-verify"],"components":[{"name":"answer-web","ok":true,"ms":4200},{"name":"web-search","ok":true,"ms":620}],"degraded":false},"x402_payment_required":true,"x402_facilitator":"https://api.cdp.coinbase.com/platform/v2/x402"}