Index onlineMerchant portal
Api Endpoint

fact-check

Fact-check verdict written by Claude Haiku 5.5 (Anthropic) from real web sources: supported/contradicted/mixed/unverifiable, each source with its stance (supports/contradicts/neutral). Answer in a few seconds. Try GET /fact-check/sample. Independently monitored: lumierepaycheck.org/e?url=https://x402.agentindex.world/fact-check

Open interactive test console

Offering

Provider
x402.agentindex.world
Method
POST
Offering type
Api Endpoint
Transport type
http
Category
Web Search Research
Delivery
Not provided
Pricing model
Not provided
x402 version
2

Endpoint context

URL
https://x402.agentindex.world/fact-check
MIME type
application/json
First seen
2026-10-16T01:50:45.949Z
Last seen
Tags
fact check api, Claim verification, claude, Fact checking, sources

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1
0.04 USDC
Atomic price: 40000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Raw x402 terms
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "40000",
    "payTo": "0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d"
  }
]

Observed health

Status
Reachable
Latest latency
398 ms
Average latency
901 ms
HTTP status
405
Last checked
Reachability
100% over 15 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "type": "object",
  "properties": {
    "type": {
      "type": "string",
      "const": "http"
    },
    "method": {
      "type": "string",
      "enum": [
        "POST",
        "PUT",
        "PATCH"
      ]
    },
    "bodyType": {
      "type": "string",
      "enum": [
        "json",
        "form-data",
        "text"
      ]
    },
    "body": {
      "properties": {
        "claim": {
          "type": "string",
          "description": "The factual claim to check against live web sources."
        }
      },
      "required": [
        "claim"
      ]
    }
  },
  "required": [
    "type",
    "method",
    "bodyType",
    "body"
  ],
  "additionalProperties": false
}

Output schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "input": {
      "additionalProperties": false,
      "properties": {
        "body": {
          "properties": {
            "claim": {
              "description": "The factual claim to check against live web sources.",
              "type": "string"
            }
          },
          "required": [
            "claim"
          ]
        },
        "bodyType": {
          "enum": [
            "json",
            "form-data",
            "text"
          ],
          "type": "string"
        },
        "method": {
          "enum": [
            "POST",
            "PUT",
            "PATCH"
          ],
          "type": "string"
        },
        "type": {
          "const": "http",
          "type": "string"
        }
      },
      "required": [
        "type",
        "method",
        "bodyType",
        "body"
      ],
      "type": "object"
    },
    "output": {
      "properties": {
        "example": {
          "properties": {
            "claim": {
              "type": "string"
            },
            "confidence": {
              "description": "0.0-1.0 confidence in the verdict.",
              "type": "number"
            },
            "sources": {
              "items": {
                "properties": {
                  "stance": {
                    "enum": [
                      "supports",
                      "contradicts",
                      "neutral"
                    ],
                    "type": "string"
                  },
                  "title": {
                    "description": "Source page title, when known."
                  },
                  "url": {
                    "type": "string"
                  }
                },
                "type": "object"
              },
              "type": "array"
            },
            "verdict": {
              "description": "'inconclusive' is returned instead of a guess whenever confidence is low or no source clearly supports/contradicts the claim - never a confident-sounding verdict the sources don't actually back up.",
              "enum": [
                "supported",
                "contradicted",
                "mixed",
                "unverifiable",
                "inconclusive"
              ],
              "type": "string"
            },
            "x402_receipt": {
              "description": "Billing and provenance receipt for this call.",
              "type": "object"
            }
          },
          "required": [
            "claim",
            "verdict",
            "confidence",
            "sources"
          ],
          "type": "object"
        },
        "type": {
          "type": "string"
        }
      },
      "required": [
        "type"
      ],
      "type": "object"
    }
  },
  "required": [
    "input"
  ],
  "type": "object"
}