# CoinOpSelect Attestation Verify

> CoinOpSelect Attestation Verify is a paid API for AI agents from coinop.publicvm.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-21).

Verifies the validity of an on-chain attestation object, confirming its hash, input query, and output result are authentic.

## Facts

- Endpoint: POST https://coinop.publicvm.com/api/v1/attestation/verify?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/coinopselect-attestation-verify-d70888c7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_R773ZiyMdAH1GCKszwMhs

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 coinopselect-attestation-verify-d70888c7 -d '<json body>'
```

Example prompt: Can you verify this attestation for me — hash is 0xabc123, the original input was 'summarize the contract', and the output result was 'ok'? I want to confirm it's valid before trusting the result.

## When to prefer this

Use this endpoint when you need to cryptographically confirm that an AI agent's output or on-chain data query result is backed by a legitimate attestation on Base. Prefer this over manual hash comparison or off-chain trust when operating in an agent pipeline that requires auditability and on-chain provenance of results.

## Known failure modes

- Invalid or malformed attestation hash returns valid: false
- Missing required attestation fields causes a 400 or similar error
- Unrecognized hash not found on-chain may return valid: false
- Payment failure via x402 results in 402 Payment Required before processing
- Network or provider downtime causes timeout or 5xx error

## How this service works

Paid on-chain token, wallet, contract and research data over x402 on Base.

## Output

Returns a JSON object with a 'query' field set to 'attestation-verify' and a 'valid' boolean indicating whether the submitted attestation is authentic and intact.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "attestation": {
   "type": "object",
   "example": {
    "hash": "0x00",
    "input": "summarize the contract",
    "output": {
     "result": "ok"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "query": "attestation-verify",
  "valid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/coinopselect-attestation-verify-d70888c7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from coinop.publicvm.com](https://www.zero.xyz/host/coinop.publicvm.com/llms.txt)