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MapleAI Fact Check
x402
MapleAI Fact Check is a paid API for AI agents from base.mapleai.shop, paid per call via x402, $0.043/call, status unknown (last checked 2026-10-11).
Verifies a text claim by gathering evidence for and against it from recent sources, returning a verdict, confidence level, and cited evidence URLs.
Price / call$0.043
Success—
StatusUnknown
How this service works
14 chat models (GPT + Claude), 7 image models, and Jev structured decisions. Pay per request in USDC on Base with x402.
Output
Returns a JSON object with the original claim, a plain-language summary, a verdict (e.g. 'confirmed', 'refuted', 'unverified'), a confidence level (e.g. 'high', 'medium', 'low'), and two arrays — evidence_for and evidence_against — each containing source URLs, notes, and source type (e.g. 'x', 'web').
Example use cases
Verify viral social media claim
“I saw a tweet saying 'the US government spent $2 trillion on foreign aid last year' — can you fact-check that claim looking at sources from the past 7 days, and show me up to 6 pieces of evidence on each side?”
Validate health or science statistic
“Can you check whether it's true that 'drinking coffee reduces the risk of Alzheimer's disease by 65%'? Look back 30 days and give me up to 10 sources for and against.”
Check accuracy of political statement
“Fact-check the claim 'Inflation in the US hit a 40-year high in 2022' — use the last 7 days of sources and return up to 5 evidence items per side with links.”
Technical details
Endpoint
POSThttps://base.mapleai.shop/v1/x/factcheck?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need a structured, sourced verdict on a specific factual claim — especially when you want both supporting and contradicting evidence with cited URLs. It is more useful than a generic chat model for fact-checking because it returns machine-readable verdicts and confidence scores with traceable sources, and more targeted than a web search API because it interprets and weighs evidence automatically.
Side effects
- Claim too vague or ambiguous for a clear verdict — returns low confidence or inconclusive
- No evidence found within the specified days_back window — evidence arrays empty
- days_back exceeds 30 or max_sources exceeds 10 — validation error
- Payment failure via x402 — request rejected before processing
- Claim text exceeds 1000 characters — rejected by schema validation
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| claim | string | The statement to verify |
| days_back | integer | How far back to look |
| max_sources | integer | Max evidence items per side; drives the price |
Output
Schema · Response
{
"type": "json",
"example": {
"claim": "...",
"object": "x.factcheck",
"summary": "...",
"verdict": "confirmed",
"confidence": "high",
"evidence_for": [
{
"url": "https://x.com/user/status/123",
"note": "...",
"source_type": "x"
}
],
"evidence_against": []
}
}Tags
x402
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