# Batch Idempotency Keys

> Batch Idempotency Keys is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-20).

Derives stable, deterministic, non-secret idempotency keys for a batch of items from caller-supplied values and a namespace, without any external provider.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/batch-idempotency-keys?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/batch-idempotency-keys-8fc9aea9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0YJUfiXX3yrFU8NsF_9NK

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 batch-idempotency-keys-8fc9aea9 -d '<json body>'
```

Example prompt: Generate stable idempotency keys for this batch of 50 order items using the namespace 'orders-2024-06' so I can safely pass them to the payment processor without risk of duplicates.

## When to prefer this

Choose this endpoint when you need to derive stable, reproducible idempotency keys for a batch of structured items before handing them to a downstream tool with a strict contract (e.g. payment processor, task queue, ETL pipeline). It is ideal when you want deterministic, namespace-scoped keys computed without any external key-management service, secret storage, or stateful provider, and when you need a versioned result contract for auditability.

## Known failure modes

- Batch exceeds 256 items — request rejected
- Individual item exceeds 128 properties — item rejected or truncated
- Namespace string exceeds 8192 characters — validation error
- Malformed input array — schema validation failure
- Network or payment processing error — HTTP 402 or 5xx returned

## How this service works

Batch Idempotency Keys: Batch Idempotency Keys derives stable non-secret idempotency keys for batch items from bounded caller-supplied values without an external provider. Call Batch Idempotency Keys before an agent hands structured data or a batch plan to a downstream tool with a stricter contract. Returns the bounded transformation or validation finding with counts, normalized values, and a versioned result contract for Batch Idempotency Keys as versioned deterministic JSON. Price: $0.001 USD…

## Output

Returns a versioned deterministic JSON object containing idempotency keys for each input item, normalized values, item counts, and a versioned result contract — all computed in-memory without data retention.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "items": {
   "type": "array",
   "items": {
    "type": "object",
    "maxProperties": 128,
    "additionalProperties": true
   },
   "maxItems": 256,
   "description": "Items supplied to Batch Idempotency Keys; used only for this bounded calculation and processed in memory without retention."
  },
  "namespace": {
   "type": "string",
   "maxLength": 8192,
   "description": "Namespace supplied to Batch Idempotency Keys; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "keys": [
    {
     "key": "a7b59420f6ae73743bb81f97fe5222c4b3db261381bd9d0d85c9bd08996d04b7",
     "index": 0
    },
    {
     "key": "884e051ec6969bb1bc6dfd28dc6b13d09cab07dc71f656acd2a398e9c5473587",
     "index": 1
    }
   ],
   "cryptographic_secret": false
  },
  "schema": "delx/util-batch-idempotency-keys/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "375be9a5b0dc421b8588d162f162af2105b72820be462c39a74f3ceab5fd0343",
   "external_calls": 0
  },
  "operation": "data_batch:batch_idempotency_keys"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/batch-idempotency-keys-8fc9aea9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)