{"openapi":"3.1.0","info":{"title":"Claim Evaluator","version":"0.1.3","description":"Fact-check API for agents: likelihood score + web sources. Tempo USDC $0.05/request (MPP); Base USDC $0.05/request (x402); Stripe SPT $0.50/request (Link CLI).","x-guidance":"Claim Evaluator scores factual claims for agents.\n\nJob: POST a single factual claim. Get back a 0–100 likelihood it is true, short reasoning, and 3–5 web sources with stance (confirm | deny | unclear). Uses live web search. Not a substitute for professional fact-checking on high-stakes decisions.\n\nCall:\n1. POST https://claim-evaluator.com/v1/evaluate\n2. Header: content-type: application/json\n3. Body: { \"claim\": \"<factual statement>\" }  (1–4000 chars)\n4. Success: HTTP 200, application/json { likelihood, reasoning, sources[] }\n5. Unpaid: HTTP 402 — pay via MPP (WWW-Authenticate) and/or x402 (PAYMENT-REQUIRED), then retry the same request\n\nFixed price: $0.05 USD per request (MPP Tempo USDC, Stripe SPT, or Base x402).\n\nPay example (Stripe Link CLI):\nnpx @stripe/link-cli mpp pay https://claim-evaluator.com/v1/evaluate -X POST -H \"content-type: application/json\" -d '{\"claim\":\"<factual claim>\"}' --context \"<why you are paying; min 100 characters>\"\n\nPay example (AgentCash / Tempo USDC via MPP — use --timeout 120000; pay + web search often exceeds the 30s default):\nnpx agentcash fetch https://claim-evaluator.com/v1/evaluate -m POST -b '{\"claim\":\"<factual claim>\"}' -H \"content-type: application/json\" --payment-protocol mpp --payment-network tempo --max-amount 1 --timeout 120000\n\nPay example (AgentCash / Base USDC via x402 — use --timeout 120000):\nnpx agentcash fetch https://claim-evaluator.com/v1/evaluate -m POST -b '{\"claim\":\"<factual claim>\"}' -H \"content-type: application/json\" --payment-protocol x402 --payment-network base --max-amount 1 --timeout 120000\n\nFree (no paywall): GET / , GET /health , GET /openapi.json , GET /examples , GET /skill.md , GET /llms.txt\n\nProof: GET /examples returns three illustrative claim evaluations (Declaration date, Earth orbit, Great Wall myth).\n\nUse when the user needs a sourced likelihood on a checkable factual claim. Skip opinions, predictions, or requests that need original research beyond web search.","contact":{"email":"support@quant-bus.com"}},"x-service-info":{"categories":["ai","research","fact-checking"],"docs":{"homepage":"https://claim-evaluator.com","apiReference":"https://claim-evaluator.com/openapi.json","llms":"https://claim-evaluator.com/llms.txt"},"logo":"https://claim-evaluator.com/logo.png","favicon":"https://claim-evaluator.com/favicon.ico"},"paths":{"/":{"get":{"summary":"Marketing homepage (HTML) or service index (JSON via Accept)","security":[],"responses":{"200":{"description":"HTML homepage for browsers; JSON index when Accept: application/json"}}}},"/health":{"get":{"summary":"Liveness check (free)","security":[],"responses":{"200":{"description":"OK","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}}}}},"/openapi.json":{"get":{"summary":"OpenAPI discovery document (free)","security":[],"responses":{"200":{"description":"OK","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}}}}},"/skill.md":{"get":{"summary":"Agent onboarding skill (free markdown)","security":[],"responses":{"200":{"description":"Markdown skill for agents"}}}},"/llms.txt":{"get":{"summary":"Short machine-readable service summary (free)","security":[],"responses":{"200":{"description":"Plain-text llms.txt"}}}},"/examples":{"get":{"summary":"Illustrative claim evaluations (free)","security":[],"responses":{"200":{"description":"OK","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}}}}},"/v1/evaluate":{"post":{"operationId":"evaluateClaim","summary":"Evaluate a factual claim: likelihood 0–100, reasoning, and web sources","tags":["Fact-checking"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","required":["claim"],"properties":{"claim":{"type":"string","description":"Single factual claim to score. Prefer concrete, checkable statements over opinions or forecasts.","minLength":1,"maxLength":4000}},"additionalProperties":false}}}},"responses":{"200":{"description":"Likelihood score with reasoning and sources","content":{"application/json":{"schema":{"type":"object","required":["likelihood","reasoning","sources"],"properties":{"likelihood":{"type":"number","minimum":0,"maximum":100,"description":"0 = definitely false, 100 = definitely true"},"reasoning":{"type":"string","description":"2–3 sentence assessment"},"sources":{"type":"array","minItems":3,"maxItems":5,"items":{"type":"object","required":["name","url","stance","summary"],"properties":{"name":{"type":"string"},"url":{"type":"string"},"stance":{"type":"string","enum":["confirm","deny","unclear"]},"summary":{"type":"string"}}}}}}}}},"400":{"description":"Invalid request body"},"402":{"description":"Payment Required (MPP challenge and/or x402 PAYMENT-REQUIRED)"},"502":{"description":"Upstream LLM / web search failure"}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.050000"},"protocols":[{"mpp":{"method":"tempo","intent":"charge","currency":"0x20c000000000000000000000b9537d11c60e8b50","amount":"0.050000","recipient":"0xDb1eC2cbaD7ECc42F0fF26DD09B1A899359f2a83"}},{"mpp":{"method":"stripe","intent":"charge","amount":"0.500000","currency":"usd","recipient":"profile_61V7YXol8mCUYNmMOA6V7YXnIzSQojeUVGkOb7HUG8T2"}},{"x402":{"network":"eip155:8453","payTo":"0xDeE6661Cb699B099dd1663f099D0Fd4032e8b496"}}]}}}}}