# Verity Claim Verification

> Verity Claim Verification is a paid API for AI agents from verity-bzw7.onrender.com, paid per call via x402, $0.25/call, status unknown (last checked 2026-09-15).

Verifies a textual claim and returns a structured verdict (supported/unsupported/uncertain) with confidence score, reasoning, and evidence

## Facts

- Endpoint: POST https://verity-bzw7.onrender.com/verify
- Price: $0.25/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/verity-claim-verification-5bf41f4b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dIdpPFFfb0isggLWLPVRK

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 verity-claim-verification-5bf41f4b -d '<json body>'
```

Example prompt: Can you verify this claim for me: 'The Eiffel Tower is taller than the Statue of Liberty' — I want to know if it's supported or unsupported, how confident you are, and what evidence backs the verdict.

## When to prefer this

Choose Verity when an AI agent needs a structured, paid, high-accountability fact-check with explicit reasoning and evidence — particularly when the output needs to be machine-readable (verdict enum + confidence float) for downstream logic. Prefer this over a generic web search when you need a single authoritative verdict rather than a list of results, or when verifying AI-generated claims before acting on them.

## Known failure modes

- Missing required 'claim' field returns a validation error
- Ambiguous or overly vague claims may return 'uncertain' with low confidence
- Claims requiring real-time data may be marked uncertain if evidence is unavailable
- Service unavailable on Render cold-start may cause timeout or 503
- Payment failure via x402 protocol blocks the request from being processed

## How this service works

Grounded reality-check with live web citations.

## Output

A structured Verdict object containing: a verdict enum ('supported', 'unsupported', or 'uncertain'), a numeric confidence score (0–1), a human-readable reasoning string explaining the judgment, and an array of evidence strings cited to support the verdict.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "claim"
 ],
 "properties": {
  "claim": {
   "type": "string"
  },
  "context": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "title": "Verdict",
 "required": [
  "verdict",
  "confidence",
  "reasoning",
  "evidence"
 ],
 "properties": {
  "verdict": {
   "enum": [
    "supported",
    "unsupported",
    "uncertain"
   ],
   "type": "string",
   "title": "Verdict"
  },
  "evidence": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "title": "Evidence"
  },
  "reasoning": {
   "type": "string",
   "title": "Reasoning"
  },
  "confidence": {
   "type": "number",
   "title": "Confidence"
  }
 },
 "description": "The structured judgment an agent pays for."
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/verity-claim-verification-5bf41f4b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from verity-bzw7.onrender.com](https://www.zero.xyz/host/verity-bzw7.onrender.com/llms.txt)