# Crawol Claim Verifier

> Crawol Claim Verifier is a paid API for AI agents from crawol.vercel.app, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-16).

Verifies a textual claim against web sources, returning a structured result with a success flag and verification data

## Facts

- Endpoint: POST https://crawol.vercel.app/api/verify
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crawol-claim-verifier-377678fa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HuR9Yvr9JbaVWIZMJKtVp

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability crawol-claim-verifier-377678fa -d '<json body>'
```

Example prompt: Can you verify this claim for me: 'The Eiffel Tower is 330 meters tall' — check it against 5 web sources and tell me if it holds up?

## When to prefer this

Choose this endpoint when you need to programmatically fact-check or validate a specific textual claim against live web content without setting up authentication or subscriptions. Ideal for AI agents that need pay-per-use, no-auth fact verification as part of automated workflows. Prefer over general web scraping endpoints when the goal is specifically to assess the truthfulness or support for a stated claim.

## Known failure modes

- Missing required 'claim' field returns a validation error
- Claim text too vague or ambiguous may yield inconclusive results
- Network timeouts on source fetching may result in partial or failed responses
- Very niche claims with limited web presence may return low-confidence or empty source data
- Payment failure via x402 results in 402 Payment Required before the request is processed

## How this service works

Web scraping and search for AI agents. No auth, no subscriptions. Pay per request in USDC via x402.

## Output

Returns a JSON object with a boolean 'success' field indicating whether the verification completed, and a 'data' object containing the structured verification results including source findings and the assessed credibility of the claim.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "claim"
 ],
 "properties": {
  "claim": {
   "type": "string",
   "description": "Claim to verify"
  },
  "sources": {
   "type": "number",
   "description": "Number of sources"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "type": "object"
  },
  "success": {
   "type": "boolean"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crawol-claim-verifier-377678fa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from crawol.vercel.app](https://www.zero.xyz/host/crawol.vercel.app/llms.txt)