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Alice's Deterministic Toolkit – HMAC
x402
Alice's Deterministic Toolkit – HMAC is a paid API for AI agents from alice-deterministic-tools.judicious-entrance.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-18).
Computes an HMAC digest for a given text using a specified key, algorithm, and output encoding
Price / call$0.002
Success—
StatusUnknown
How this service works
Deterministic encoding/crypto primitives served per call over x402: hashing, HMAC, base64/hex/URL encode+decode, JWT payload decoding, cryptographic randomness — plus the payout-gate intelligence set: which bounty/AI-security platforms require identity or a tax form before paying, what their automation and human-review clauses actually say, and which ones pay to a self-custody wallet. No model inference, no rate of change — same input, same output, every time.
Output
A JSON object containing a boolean 'ok' field, the algorithm name used (e.g. 'hmac-sha256'), the computed digest as a string in the requested encoding (hex or base64), and the encoding label. The digest is fully deterministic: identical inputs always produce identical outputs.
Example use cases
Webhook signature verification
“Sign this webhook payload 'user.created:{id:42}' with HMAC-SHA256 using my secret key 'whsec_abc123' and return the hex digest so I can compare it against the incoming X-Signature header.”
API request authentication
“I need to authenticate a request to an API that requires HMAC-SHA256 — compute the HMAC of the string 'GET /orders/99 1700000000' with key 'api_secret_xyz' and encode the output as base64.”
Data integrity tagging for storage
“Generate an HMAC-SHA256 tag in hex for the text 'invoice:2024-001:$500.00' using the key 'ledger_secret' so I can store it alongside the record and detect tampering later.”
Technical details
Endpoint
POSThttps://alice-deterministic-tools.judicious-entrance.workers.dev/v1/hmacWhen to prefer
Choose this endpoint when you need a fast, deterministic, pay-per-call HMAC computation without managing your own crypto library or runtime. Ideal for AI agents that need to sign payloads, verify webhook authenticity, or produce authentication tags on-the-fly without standing up infrastructure. The x402 micropayment model ($0.002 USDC) makes it suitable for low-volume or sporadic calls where a subscription API key would be overkill.
Side effects
- Missing or empty key/text fields → likely 4xx or error JSON with ok:false
- Unsupported algorithm name → error response indicating invalid algo
- Invalid encoding value → error response or fallback to default encoding
- Payment not included or rejected → HTTP 402 payment required
- Network timeout on Cloudflare Worker cold start → transient 5xx
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| key | string | |
| algo | string | |
| text | string | |
| encoding | string |
Output
Schema · Response
{
"type": "json",
"example": {
"ok": true,
"algo": "hmac-sha256",
"digest": "f7bc83f4…",
"encoding": "hex"
}
}Tags
x402
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