# verify.agentutil.net Fact Verification

> verify.agentutil.net Fact Verification is a paid API for AI agents from verify.agentutil.net, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-14).

Verifies a natural language claim and returns a verdict, confidence score, and current ground truth

## Facts

- Endpoint: POST https://verify.agentutil.net/v1/verify
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/verify-agentutil-net-1b3f47c3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TUaCf5oa-Hh2MUjBPi01b

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 verify-agentutil-net-1b3f47c3 -d '<json body>'
```

Example prompt: Can you fact-check this claim for me and tell me how confident you are: 'Apple is currently the most valuable public company in the world' — run it as a financial category check and give me the verdict plus the current truth.

## When to prefer this

Use this endpoint when an agent needs to programmatically verify a discrete factual claim and receive a structured verdict with confidence, especially for financial, entity, geographic, or general fact-check categories. Prefer this over web-search-based approaches when you need a structured true/false/uncertain output with a confidence score rather than raw search results.

## Known failure modes

- Claim exceeds 500-character limit — returns validation error
- Invalid or missing category enum value — returns 400 bad request
- Claim is ambiguous or unverifiable — may return low-confidence or uncertain verdict
- Payment not provided or insufficient — returns 402 Payment Required
- Service temporarily unavailable — returns 503

## How this service works

Fact verification — returns verdict, confidence, current truth

## Output

Returns a verdict (true/false/uncertain), a confidence score indicating how certain the system is, and the current ground truth or corrected information relevant to the claim.

## Example request

```json
{
 "claim": "The Earth orbits around the Sun",
 "category": "factcheck"
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "claim": {
   "type": "string",
   "maxLength": 500,
   "description": "Natural language claim to verify"
  },
  "category": {
   "enum": [
    "financial",
    "entity",
    "geo",
    "factcheck"
   ],
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/verify-agentutil-net-1b3f47c3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from verify.agentutil.net](https://www.zero.xyz/host/verify.agentutil.net/llms.txt)