# SHA3-256 Digest as Base64URL

> SHA3-256 Digest as Base64URL is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-01).

Computes a SHA3-256 cryptographic hash of input text and returns it encoded as base64url

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-sha3-256-base64url?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sha3-256-digest-as-base64url-f73cfc7c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cpIA3DcrHah3PYDWoQUHb

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 sha3-256-digest-as-base64url-f73cfc7c -d '<json body>'
```

Example prompt: Can you compute the SHA3-256 hash of the text 'Hello, World!' and give me the result encoded as base64url?

## When to prefer this

Choose this endpoint when you specifically need SHA3-256 (Keccak family, not SHA-2) output in base64url encoding — particularly when the digest must be safe for URL or filename use without additional encoding. Prefer the free sandbox variant (/v1/sandbox/digest-sha3-256-base64url) for testing. Use this paid version in production or when sandbox access is unavailable.

## Known failure modes

- Text exceeds 100,000 character limit — request rejected
- Empty text or key field — validation error
- Malformed JSON body — 400 bad request
- Payment not included or insufficient — 402 payment required
- Network timeout during payment processing

## How this service works

Call when an agent needs a sha3-256 digest of text, encoded as base64url. No network and no LLM. Exact $0.005 USDC. Prefer unpaid POST /v1/sandbox/digest-sha3-256-base64url first.

## Output

Returns a SHA3-256 cryptographic digest of the submitted text, encoded as a base64url string. The output is deterministic and suitable for use as a fingerprint, checksum, or compact identifier in URLs and headers.

## 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/sha3-256-digest-as-base64url-f73cfc7c/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)