# Blake2b-512 Base64url Digest (UTF-16LE)

> Blake2b-512 Base64url Digest (UTF-16LE) is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.009/call, status unknown (last checked 2026-09-29).

Computes a BLAKE2b-512 keyed or unkeyed digest of a UTF-16LE-encoded text string and returns it as a base64url-encoded string.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-blake2b512-base64url-utf16?utm_source=zero.xyz
- Price: $0.009/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blake2b-512-base64url-digest-utf-16le-9e09d9ed
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bcGPoz1F2_Nk3B7L1f4D3

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 blake2b-512-base64url-digest-utf-16le-9e09d9ed -d '<json body>'
```

Example prompt: Can you give me the BLAKE2b-512 hash of the text 'Hello, World!' encoded as UTF-16LE and return it as base64url? Use the key 'mysecretkey'.

## When to prefer this

Choose this endpoint when you specifically need a BLAKE2b-512 digest of text treated as UTF-16LE bytes with base64url output encoding — for example when matching a specific hash format used by a .NET or Windows application, or when integrating with systems that require BLAKE2b over UTF-16LE rather than SHA-256 or UTF-8. Prefer the free sandbox endpoint at /v1/sandbox/digest-blake2b512-base64url-utf16 for testing before paying.

## Known failure modes

- Text or key exceeds maximum length (100,000 or 512 chars) — returns validation error
- Empty text or key supplied — rejected by schema minLength constraint
- Malformed request body (missing required fields) — 400 bad request
- Payment not provided or insufficient USDC — 402 payment required
- Service temporarily unavailable — 5xx error

## How this service works

Call when an agent needs a blake2b512 digest of utf16le bytes, encoded as base64url. Exact $0.009 USDC. Prefer unpaid POST /v1/sandbox/digest-blake2b512-base64url-utf16 first.

## Output

Returns a base64url-encoded string representing the BLAKE2b-512 digest of the UTF-16LE-encoded input text, optionally keyed with the provided key 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/blake2b-512-base64url-digest-utf-16le-9e09d9ed/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)