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HMAC of a message under a key
x402
HMAC of a message under a key is a paid API for AI agents from twin.unykorn.org, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-01).
Computes an HMAC (keyed-hash message authentication code) for a given message and secret key using a specified algorithm
Price / call$0.002
Success—
StatusUnknown
How this service works
HMAC of a message under a key — Genesis402 / UnyKorn Operator Network
Output
Returns a JSON object with ok:true, the type field set to 'hash-hmac', the computed HMAC digest, and a payment receipt containing the transaction hash, USD amount, and receipt ID.
Example use cases
Webhook signature verification
“Calculate the HMAC-SHA256 of the payload 'user_id=42&event=purchase' with the shared secret 'wh_secret_abc123' so I can check it against the signature header from this incoming webhook.”
API request signing
“I need to sign my API request body 'GET /api/orders?page=1' using HMAC-SHA512 with the key 'api_private_key_xyz' before sending it to the server.”
Data integrity tagging
“Generate an HMAC-MD5 authentication tag for the string 'invoice_id=9981&amount=250.00' using the key 'billing-secret-key' so I can store it alongside the record to detect tampering.”
Technical details
Endpoint
POSThttps://twin.unykorn.org/hash-hmac?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need a simple, pay-per-call HMAC computation without managing your own cryptographic infrastructure — ideal for agents that occasionally need to sign messages, verify webhook payloads, or authenticate data on demand without a persistent server-side HMAC library. Particularly useful when the algorithm is configurable and you need a trusted third-party computation.
Side effects
- Missing or invalid key returns an error response
- Unsupported algorithm name causes a failure
- Text exceeding 49152 characters is rejected
- Malformed hex input (not matching 0x[hex] pattern) returns a validation error
- Network or payment processing failure returns a non-ok response
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| params | object |
Output
Schema · Response
{
"type": "json",
"example": {
"ok": true,
"type": "hash-hmac",
"receipt": {
"tx_hash": "0x<64hex>",
"amount_usd": 0.002,
"receipt_id": "g402-<16hex>"
},
"generated_at": "<iso8601>"
}
}Tags
x402
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