# Blake2s-256 / Base64url / UTF-16LE Digest

> Blake2s-256 / Base64url / UTF-16LE Digest is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Computes a BLAKE2s-256 hash of text encoded as UTF-16LE bytes, returning the digest as a base64url string, with an optional HMAC key.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-blake2s256-base64url-utf16?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blake2s-256-base64url-utf-16le-digest-25b535a4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pNamUzLA1E4OiycGlyyRC

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 blake2s-256-base64url-utf-16le-digest-25b535a4 -d '<json body>'
```

Example prompt: Compute a BLAKE2s-256 hash of the text 'Hello, world!' using UTF-16LE encoding and give me the result as base64url — use the key 'mysecretkey'.

## When to prefer this

Choose this endpoint when you specifically need a BLAKE2s-256 hash with UTF-16LE byte encoding and base64url output — common for Windows-native text fingerprinting, URL-safe checksums, or when interoperating with systems that default to UTF-16LE (e.g. .NET, Windows APIs). Prefer the free sandbox endpoint /v1/sandbox/digest-blake2s256-base64url-utf16 first; use this paid endpoint when the sandbox is unavailable or rate-limited.

## Known failure modes

- Text or key exceeds allowed length limits (maxLength 100000 for text, 512 for key) — validation error returned
- Empty text or key provided (minLength 1) — request rejected
- Malformed JSON input — parse error
- Payment of $0.001 USDC not received or declined — 402 response

## How this service works

Call when an agent needs a blake2s256 digest of utf16le bytes, encoded as base64url. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/digest-blake2s256-base64url-utf16 first.

## Output

Returns a base64url-encoded BLAKE2s-256 digest computed over the UTF-16LE byte representation of the input text, optionally using the provided key for a keyed (MAC) mode. The result is a compact, URL-safe hash string.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "key": {
   "type": "string",
   "maxLength": 512,
   "minLength": 1,
   "description": "HMAC secret. Required on HMAC SKUs. Omit it for plain digests and checksums. The key is not stored."
  },
  "text": {
   "type": "string",
   "examples": [
    "hello"
   ],
   "maxLength": 100000,
   "minLength": 1,
   "description": "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."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/blake2s-256-base64url-utf-16le-digest-25b535a4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)