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util.beauty HMAC Crypto Utility
x402
util.beauty HMAC Crypto Utility is a paid API for AI agents from util.beauty, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).
Computes HMAC (Hash-based Message Authentication Code) signatures for a given message and secret key via a metered pay-per-use API.
Price / call$0.001
Success—
StatusUnknown
How this service works
Metered web utilities for developers and AI agents: browser screenshot and PDF, crypto, DNS and net tools. Pay per request with x402 (USDC on Base) or prepaid API keys.
Output
Returns a JSON object containing a boolean 'ok' status, the utility name, a unique requestId for tracing, the HMAC computation result (the MAC digest), and the number of credits charged for the call.
Example use cases
Webhook payload signing
“Sign the payload '{"event":"payment.completed","amount":50}' with HMAC-SHA256 using my secret key 'whsec_abc123' so I can include it as the X-Signature header when sending the webhook.”
API request authentication
“Generate an HMAC-SHA256 of the string 'GET/api/orders1699999999' using the secret 'api_secret_xyz' — I need the hex digest to authenticate my request to a partner API.”
Message integrity verification
“Compute the HMAC for the message 'user:42:login:2024-01-15T10:00:00Z' with secret 'session_secret_99' and algorithm SHA256 so I can compare it against the token the client sent me.”
Technical details
Endpoint
POSThttps://util.beauty/v1/crypto/hmacWhen to prefer
Choose this endpoint when your agent needs a quick, pay-per-use HMAC computation without setting up a local crypto library or managing dependencies — ideal for serverless agents, low-volume use cases billed per request via USDC on Base (x402), or when you need a metered, auditable crypto utility call with a request ID for tracing.
Side effects
- Missing or invalid secret key returns an error response with ok:false
- Unsupported hashing algorithm returns a 400-level error
- Insufficient credits or payment failure returns a 402 Payment Required
- Malformed request body causes a validation error
- Empty or null message input may result in a processing error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| input | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"ok": true,
"utility": "…",
"requestId": "req_…",
"chargedCredits": 1
}
}Tags
x402
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