# x402-gateway: verify_batch (Semaphore ZK Proof Batch Verifier)

> x402-gateway: verify_batch (Semaphore ZK Proof Batch Verifier) is a paid API for AI agents from x402.freeq.one, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-13).

Batch-verifies up to 10 Semaphore ZK proofs in a single pay-per-call request, returning per-proof results with total count and average verification duration.

## Facts

- Endpoint: POST https://x402.freeq.one/tools/verify_batch
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-gateway-verify-batch-semaphore-zk-proof-batch-verifier-5a0e0093
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gA72kSJ1yhkOz6W-pfKhO

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 x402-gateway-verify-batch-semaphore-zk-proof-batch-verifier-5a0e0093 -d '<json body>'
```

Example prompt: I have 8 Semaphore Groth16 proofs from our anonymous voting system — can you batch-verify all of them at once and tell me which ones passed, which failed, and what the average verification time was?

## When to prefer this

Choose this endpoint when you need to verify multiple Semaphore ZK proofs efficiently in a single API call rather than making repeated single-proof requests. It is ideal for applications performing bulk identity checks, anonymous voting tallies, or airdrop eligibility verification where up to 10 proofs must be validated together with per-proof granularity and timing metrics. Prefer it over the single verify_semaphore endpoint when batch throughput and consolidated reporting matter.

## Known failure modes

- More than 10 proofs submitted — batch limit exceeded
- Malformed or invalid Groth16 proof format — verification error per proof
- Missing required fields in proof objects — 400 bad request
- Payment failure via x402 protocol — 402 Payment Required
- Network timeout for large batches — partial or no results returned

## How this service works

x402-gateway tool: verify_batch — Batch verify up to 10 Semaphore proofs in a single request. Returns per-proof results with total count and average duration.

## Output

Returns a structured JSON response containing per-proof verification results (pass/fail for each of up to 10 Semaphore Groth16 proofs), the total number of proofs processed, and the average duration taken to verify across all proofs in the batch.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "items": {
   "type": "array",
   "items": {
    "type": "object",
    "properties": {
     "proof": {
      "type": "object",
      "description": "Semaphore proof object"
     }
    }
   },
   "maxItems": 10,
   "description": "Array of up to 10 Semaphore proof objects to verify"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-gateway-verify-batch-semaphore-zk-proof-batch-verifier-5a0e0093/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.freeq.one](https://www.zero.xyz/host/x402.freeq.one/llms.txt)