# BLAKE2s-256 Digest as Base64URL

> BLAKE2s-256 Digest as Base64URL is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Computes a BLAKE2s-256 cryptographic hash of input text and returns it encoded as base64url, with no network calls or LLM involved.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-blake2s256-base64url?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blake2s-256-digest-as-base64url-d8798533
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3NyurpK5NYpvjQpt2gg4b

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-digest-as-base64url-d8798533 -d '<json body>'
```

Example prompt: Can you compute a BLAKE2s-256 hash of the text 'Hello, world!' and give me the result encoded as base64url?

## When to prefer this

Choose this endpoint when you need a fast, deterministic BLAKE2s-256 hash of text encoded specifically as base64url (not hex or standard base64). Prefer this over the sibling blake2s256-base64 endpoint when the output must be URL-safe. Use the free sandbox endpoint (/v1/sandbox/digest-blake2s256-base64url) first to test; pay only when you need production reliability. Ideal for agents requiring compact, URL-safe cryptographic fingerprints without any network or AI overhead.

## Known failure modes

- Text or key exceeds length limits (text > 100,000 chars or key > 512 chars) — returns 4xx validation error
- Missing or empty text field — returns 4xx validation error
- Payment not provided or insufficient — returns 402 Payment Required
- Malformed request body — returns 4xx parse error

## How this service works

Call when an agent needs a blake2s256 digest of text, encoded as base64url. No network and no LLM. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/digest-blake2s256-base64url first.

## Output

Returns a BLAKE2s-256 cryptographic digest of the input text, encoded as a base64url string. If a key is provided, a keyed variant of the hash is produced. The result is deterministic and compact, suitable for checksums, deduplication, and integrity verification.

## 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-digest-as-base64url-d8798533/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)