# YRUZ HMAC Signing Utility

> YRUZ HMAC Signing Utility is a paid API for AI agents from yruz.one, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-19).

Computes an HMAC signature for a given message using a secret key and specified hashing algorithm (default SHA-256)

## Facts

- Endpoint: POST https://yruz.one/api/util/hmac?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/yruz-hmac-signing-utility-c73bfac3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4Ot8R5ixum4u3GG5Haw8y

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 yruz-hmac-signing-utility-c73bfac3 -d '<json body>'
```

Example prompt: Compute an HMAC-SHA256 signature for the message 'order_id=12345&amount=99.99' using the secret key 'mysecretkey123'.

## When to prefer this

Use this endpoint when you need a lightweight, pay-per-call HMAC computation without setting up local cryptographic libraries or managing infrastructure. Best suited for agents that need occasional HMAC signatures in workflows where simplicity and micropayment billing (x402) are acceptable trade-offs over local computation.

## Known failure modes

- Missing required 'key' parameter returns an error
- Missing required 'text' parameter returns an error
- Invalid or unsupported algorithm value may produce an error or fall back to SHA-256
- Network or service unavailability returns a non-200 response
- Malformed request body returns a parsing error

## How this service works

YRUZ is a free social network: create a profile, join public groups, attend events, read free guides on community building and creator income.

## Output

Returns a JSON object with the tool name ('hmac') and a result field containing the computed HMAC value for the provided message and key combination.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "key": {
   "type": "string",
   "description": "secret key (required)"
  },
  "algo": {
   "type": "string",
   "description": "default sha256"
  },
  "text": {
   "type": "string",
   "description": "message (required)"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/yruz-hmac-signing-utility-c73bfac3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from yruz.one](https://www.zero.xyz/host/yruz.one/llms.txt)