SAVER Verifier Fact Checking
Fact-checking and claim verification API for AI agents. Verify whether a cited source supports a claim; check statistics, dates, units and populations in research reports before publication. Separate web research returns a verdict, linked evidence and sources. Source verification is model-assessed, not guaranteed correct. POST /v2/verify; x402 v2 on Base; 0.20 USDC. No signup or API key.
Offering
- Provider
- api.saververify.com
- Method
- POST
- Offering type
- Api Endpoint
- Transport type
- http
- Category
- Other
- Delivery
- Not provided
- Pricing model
- Not provided
- x402 version
- 2
Endpoint context
- URL
https://api.saververify.com/v2/verify- MIME type
- Not provided
- First seen
- 2026-10-19T02:32:25.008Z
- Last seen
- Tags
- fact-checking, claim-verification, statistics, source-attribution, research-reports
Payment pricing
x402 payment terms are the authoritative price for calling this endpoint.
- Payment option 1
- 0.2 USDC
Atomic price: 200000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Raw x402 terms
[
{
"scheme": "exact",
"network": "eip155:8453",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "200000",
"payTo": "0xdfd6cb683F5288e1dD1337E84C09b490857CC110"
}
]Observed health
- Status
- Healthy
- Latest latency
- 120 ms
- Average latency
- 462 ms
- HTTP status
- 200
- Last checked
- Reachability
- 100% over 12 checks
Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.
Input schema
{
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"claim": {
"description": "One factual claim to check, preserving its figures, dates and qualifications.",
"maxLength": 8000,
"minLength": 1,
"pattern": "\\S",
"type": "string"
},
"context": {
"description": "Optional source URL, publication date, reporting period, jurisdiction or definitions needed to assess the claim; null is absent. At most 12000 UTF-16 code units.",
"maxLength": 12000,
"type": [
"string",
"null"
]
}
},
"required": [
"claim"
],
"type": "object"
},
"bodyType": {
"enum": [
"json"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
}Output schema
{
"properties": {
"example": {
"additionalProperties": false,
"properties": {
"confidence": {
"maximum": 1,
"minimum": 0,
"type": "number"
},
"confidenceType": {
"const": "model_assessed",
"type": "string"
},
"domain": {
"type": "string"
},
"evidence": {
"items": {
"additionalProperties": false,
"properties": {
"id": {
"type": "string"
},
"relation": {
"enum": [
"supports",
"contradicts",
"context"
],
"type": "string"
},
"sourceIds": {
"items": {
"type": "string"
},
"minItems": 1,
"type": "array",
"uniqueItems": true
},
"text": {
"type": "string"
}
},
"required": [
"id",
"text",
"relation",
"sourceIds"
],
"type": "object"
},
"maxItems": 10,
"type": "array"
},
"explanation": {
"type": "string"
},
"requestId": {
"type": "string"
},
"schemaVersion": {
"const": "2.0",
"type": "string"
},
"sources": {
"items": {
"additionalProperties": false,
"properties": {
"id": {
"type": "string"
},
"title": {
"type": "string"
},
"url": {
"format": "uri",
"type": "string"
}
},
"required": [
"id",
"title",
"url"
],
"type": "object"
},
"type": "array"
},
"status": {
"enum": [
"supported",
"contradicted",
"mixed",
"insufficient_evidence"
],
"type": "string"
},
"timestamp": {
"format": "date-time",
"type": "string"
}
},
"required": [
"status",
"confidence",
"explanation",
"evidence",
"sources",
"domain",
"timestamp",
"schemaVersion",
"requestId",
"confidenceType"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}