# CAPI2 Agent Commerce Claim Verifier

> CAPI2 Agent Commerce Claim Verifier is a paid API for AI agents from capi2-agent-commerce.vandurmedries.workers.dev, paid per call via x402, $0.1/call, status unknown (last checked 2026-09-14).

Verifies a sustainability or commerce claim against provided evidence URLs and returns a confidence score with verification status and supporting sources.

## Facts

- Endpoint: POST https://capi2-agent-commerce.vandurmedries.workers.dev/v1/claim-verify
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/capi2-agent-commerce-claim-verifier-a74863de
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9S29_z_-oKiAt_0-pqQDC

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-agent-commerce-claim-verifier-a74863de -d '<json body>'
```

Example prompt: Can you verify the claim 'Our packaging is 100% recycled materials' made by EcoVend at https://ecovend.com, using these two sources as evidence: https://ecovend.com/materials-report and https://thirdparty-audit.org/ecovend-2024?

## When to prefer this

Choose this endpoint when you need a machine-verifiable, evidence-backed assessment of a sustainability or commerce claim from a specific vendor, especially when you want a confidence score and traceable evidence URLs rather than a simple yes/no. It is particularly suited for agent workflows requiring receipts or audit trails for ESG, green, or product claims before publishing, approving, or transacting.

## Known failure modes

- Claim text too short (below 3 characters) or too long (above 1200 characters) returns a 400 validation error
- Invalid or unreachable vendor_url returns an error or lowers confidence
- Source URLs that are inaccessible or irrelevant may result in low confidence score
- More than 3 source URLs provided returns a 400 validation error
- Payment of 0.1 USDC not completed via x402 protocol results in a 402 Payment Required response
- Malformed URI in vendor_url or source_urls returns schema validation error

## How this service works

Programmable authority checks and tamper-evident receipts for autonomous agents, sold through sustainable x402 commerce.

## Output

A JSON object containing a confidence score (0–1 float), a verification_status string (e.g. 'supported', 'unsupported', 'uncertain'), and an array of evidence_source_urls that substantiate the verification result.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "claim": {
   "type": "string",
   "maxLength": 1200,
   "minLength": 3
  },
  "vendor_url": {
   "type": "string",
   "format": "uri"
  },
  "source_urls": {
   "type": "array",
   "items": {
    "type": "string",
    "format": "uri"
   },
   "maxItems": 3
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "confidence": 0.88,
  "verification_status": "supported",
  "evidence_source_urls": [
   "https://example.com/security"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/capi2-agent-commerce-claim-verifier-a74863de/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from capi2-agent-commerce.vandurmedries.workers.dev](https://www.zero.xyz/host/capi2-agent-commerce.vandurmedries.workers.dev/llms.txt)