# SHA-512/256 Base64url Digest of Hex Bytes

> SHA-512/256 Base64url Digest of Hex Bytes is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-29).

Computes a SHA-512/256 hash of raw hex-encoded bytes and returns the result encoded as base64url

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-sha512-256-base64url-rawhex?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sha-512-256-base64url-digest-of-hex-bytes-9f00f080
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_y8tGrx-n7JOa9yYla6Zk2

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 sha-512-256-base64url-digest-of-hex-bytes-9f00f080 -d '<json body>'
```

Example prompt: Compute the SHA-512/256 hash of these raw hex bytes '48656c6c6f' and give me the result encoded as base64url.

## When to prefer this

Choose this endpoint when you specifically need a SHA-512/256 digest of raw bytes supplied as hex, with the output formatted as base64url — not hex or base64. Prefer the free sandbox endpoint POST /v1/sandbox/digest-sha512-256-base64url-rawhex when available. Use this paid endpoint when the sandbox is unavailable or rate-limited. For plain SHA-256 or MD5 hex digests, use the sibling endpoint instead.

## Known failure modes

- Invalid or non-hex input text causes a processing error
- Input text exceeds 100,000 character limit returns an error
- Empty key or text fields are rejected due to minLength:1 constraint
- Payment of $0.001 USDC not provided results in 402 Payment Required response
- Malformed hex string (odd length or invalid characters) may cause digest failure

## How this service works

Call when an agent needs a sha512-256 digest of hex bytes, encoded as base64url. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/digest-sha512-256-base64url-rawhex first.

## Output

Returns the SHA-512/256 cryptographic digest of the input interpreted as raw hex bytes, encoded as a base64url string suitable for use in URLs, tokens, or compact representations.

## 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": [
    "68656c6c6f"
   ],
   "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/sha-512-256-base64url-digest-of-hex-bytes-9f00f080/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)