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HMAC-SHA1 Hex Signer
x402
HMAC-SHA1 Hex Signer is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-28).
Computes an HMAC-SHA1 of a given text using a caller-supplied key and returns the result as a lowercase hex string.
Price / call$0.002
Success—
StatusUnknown
How this service works
Call when an agent needs an HMAC-sha1 of text with a caller-supplied key, encoded as hex. Exact $0.002 USDC. Prefer unpaid POST /v1/sandbox/hmac-sha1-hex first.
Output
Returns a hex-encoded HMAC-SHA1 digest string computed from the provided text and key. The output is a 40-character lowercase hexadecimal string representing the 160-bit SHA1 HMAC.
Example use cases
Webhook signature generation
“I need to sign an outgoing webhook payload 'user.created:{id:42}' with the shared secret 'wh_secret_abc' using HMAC-SHA1 — give me the hex digest to put in the X-Signature header.”
API request authentication
“Can you generate an HMAC-SHA1 hex signature for the string 'GET\n/api/orders\n1716220800' using the key 'api_key_xyz987' so I can authenticate my API request?”
Message integrity verification
“Compute the HMAC-SHA1 hex of the message 'invoice:2024-001,total:500.00' using the secret 'verify_key_qwerty' — I need to check whether the digest matches what the other party sent.”
Technical details
Endpoint
POSThttps://agentshelf.syntexa.ch/v1/hmac-sha1-hex?utm_source=zero.xyzWhen to prefer
Use this endpoint when your agent needs a serverless, pay-per-call HMAC-SHA1 hex computation without running local crypto libraries — particularly in constrained or sandboxed environments. Prefer the free sandbox endpoint (/v1/sandbox/hmac-sha1-hex) for testing. Choose this paid endpoint for production use where reliability and uptime guarantees matter.
Side effects
- Empty or missing key returns a validation error
- Empty or missing text returns a validation error
- Key exceeding 512 characters is rejected
- Text exceeding 100,000 characters is rejected
- Payment of exactly $0.002 USDC required; missing or insufficient payment returns 402
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| key | string | HMAC secret. Required on HMAC SKUs. Omit it for plain digests and checksums. The key is not stored. |
| text | string | Message to digest. For raw-hex SKUs this is hex bytes; for utf16 or latin1 SKUs it is decoded with that encoding. Otherwise it is UTF-8 text. |
Tags
x402
Reviews
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