# capi2 Claim Verify

> capi2 Claim Verify is a paid API for AI agents from capi2-claim-verify.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Verifies vendor, compliance, security, or commercial claims against supplied public evidence URLs, returning a verdict and confidence score.

## Facts

- Endpoint: POST https://capi2-claim-verify.onrender.com/v1/procurement-claim-check
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/capi2-claim-verify-a68ec39d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_di5uEurf40NOWlhDGrjSM

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 capi2-claim-verify-a68ec39d -d '<json body>'
```

Example prompt: Check whether Acme Corp's claim that 'all customer data is encrypted at rest and in transit' is supported by evidence on their security page at https://acmecorp.com/security — I need to know the verdict and how confident you are.

## When to prefer this

Choose this endpoint when you need evidence-grounded claim verification against specific public URLs rather than open-web search. It is purpose-built for procurement, vendor due diligence, and compliance workflows where you have a concrete textual claim and one or more authoritative source URLs to check against. Prefer it over generic web search when you want a structured verdict and confidence score you can pipe directly into a decision workflow.

## Known failure modes

- Supplied URL is unreachable or returns non-200 — source_results will show failed status and evidence will be empty
- Claim text is too short (<3 chars) or too long (>1200 chars) — returns 400 validation error
- No relevant evidence found at the URL — verdict may be INCONCLUSIVE or UNSUPPORTED with low confidence
- Micropayment via x402 fails or wallet has insufficient USDC — payment rejected before processing
- URL content is behind a login or paywall — only publicly accessible content is checked

## How this service works

Agent-native evidence-backed claim verification with x402 micropayments on Base USDC.

## Output

Returns a structured JSON object containing a verdict (e.g. SUPPORTED_BY_SUPPLIED_SOURCE, UNSUPPORTED, INCONCLUSIVE), a confidence score (0–1), extracted evidence snippets with relevance scores, an evidence summary, source check statuses, caveats about scope, and a timestamped request ID. The agent can use the verdict and confidence to make procurement or compliance decisions.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "claim": {
   "type": "string",
   "maxLength": 1200,
   "minLength": 3,
   "description": "Vendor, product, compliance, security, or commercial claim to verify."
  },
  "claim_id": {
   "type": "string",
   "maxLength": 200
  },
  "vendor_url": {
   "type": "string",
   "format": "uri",
   "description": "Public source URL containing evidence relevant to the claim."
  },
  "source_urls": {
   "type": "array",
   "items": {
    "type": "string",
    "format": "uri"
   },
   "maxItems": 3,
   "minItems": 1,
   "description": "Optional list of up to three public evidence URLs. These are checked together; vendor_url remains supported for backward compatibility.",
   "uniqueItems": true
  },
  "vendor_name": {
   "type": "string",
   "maxLength": 200
  },
  "request_type": {
   "type": "string",
   "maxLength": 120
  },
  "verification_type": {
   "type": "string",
   "maxLength": 120
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "claim": "Vendor states that customer data is encrypted at rest.",
  "caveats": [
   "Checks only the supplied public URL."
  ],
  "verdict": "SUPPORTED_BY_SUPPLIED_SOURCE",
  "evidence": [
   {
    "text": "Customer data is encrypted at rest.",
    "score": 0.9,
    "source_url": "https://example.com/security"
   }
  ],
  "protocol": "capi2.claim_verify/1.6.1",
  "checked_at": "2026-08-26T15:00:00Z",
  "confidence": 0.88,
  "request_id": "cv_018f5f8f0c2b4f7a",
  "vendor_url": "https://example.com/security",
  "source_results": [
   {
    "status": "checked",
    "final_url": "https://example.com/security",
    "requested_url": "https://example.com/security"
   }
  ],
  "sources_checked": 1,
  "evidence_summary": "Customer data is encrypted at rest.",
  "verification_result": "supported",
  "verification_status": "supported",
  "evidence_source_urls": [
   "https://example.com/security"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/capi2-claim-verify-a68ec39d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from capi2-claim-verify.onrender.com](https://www.zero.xyz/host/capi2-claim-verify.onrender.com/llms.txt)