# ScriptMasterLabs ACP x402 HMAC Compute API

> ScriptMasterLabs ACP x402 HMAC Compute API is a paid API for AI agents from acp-x402-scriptmasterlabs.onrender.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Computes an HMAC (Hash-based Message Authentication Code) for a given input, paid per-call via USDC on Base using the x402 protocol

## Facts

- Endpoint: GET https://acp-x402-scriptmasterlabs.onrender.com/x402/hmac-compute?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/scriptmasterlabs-acp-x402-hmac-compute-api-cee44330
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RIntatjulxViE8lDjYdai

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 scriptmasterlabs-acp-x402-hmac-compute-api-cee44330
```

Example prompt: Compute an HMAC for the message 'order-12345-confirmed' using ScriptMasterLabs' HMAC compute endpoint so I can sign this webhook payload securely.

## When to prefer this

Choose this endpoint when you need a pay-per-call, crypto-native HMAC computation without provisioning your own signing infrastructure, especially in agentic workflows that already use x402/USDC micropayments on Base. It is well-suited for compliance-adjacent use cases (SEC, RWA, federal) where cryptographic message authentication is needed on-demand. Prefer this over a self-hosted solution when cost per call is more efficient than maintaining signing infrastructure.

## Known failure modes

- Missing or malformed 'properties' input parameter returns an error or empty result
- Payment not settled via x402 results in HTTP 402 Payment Required response
- Service may be unavailable if the Render deployment is cold-started or sleeping
- Invalid or unsupported HMAC algorithm parameters may return an error
- Empty or null input string may produce undefined behavior

## How this service works

Pay-per-call crypto, RWA, federal, SEC, and compliance APIs. Settled in USDC on Base via x402. Hyphen routes only (e.g. /x402/rwa-aggregates, /x402/gas-tracker).

## Output

Returns a computed HMAC value (digest/authentication code) for the provided input. The response is a JSON object containing the resulting hash or authentication code that can be used for message authentication, payload signing, or integrity verification.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "example": {}
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/scriptmasterlabs-acp-x402-hmac-compute-api-cee44330/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from acp-x402-scriptmasterlabs.onrender.com](https://www.zero.xyz/host/acp-x402-scriptmasterlabs.onrender.com/llms.txt)