# AgentShelf SHAKE256 Hex Digest

> AgentShelf SHAKE256 Hex Digest 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 SHAKE256 hash of the provided text and returns the result encoded as a hexadecimal string

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/digest-shake256-hex?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/agentshelf-shake256-hex-digest-e9a2cfda
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VdH2hbP3jnMHgxpBXfzM6

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 agentshelf-shake256-hex-digest-e9a2cfda -d '<json body>'
```

Example prompt: Compute the SHAKE256 hex digest of this text: 'The quick brown fox jumps over the lazy dog'

## When to prefer this

Choose this endpoint when you need a SHAKE256 digest specifically encoded as hexadecimal (rather than base64 or other encodings), and want a fast, deterministic, no-dependency computation without involving an LLM or external network call. Prefer the free sandbox equivalent (/v1/sandbox/digest-shake256-hex) for testing. Use this paid version for production workflows requiring reliable uptime and guaranteed response.

## Known failure modes

- Empty or missing 'text' field returns a validation error
- Text exceeding 100,000 characters is rejected
- Missing or empty 'key' field returns a validation error
- Key exceeding 512 characters is rejected
- Insufficient USDC balance results in payment failure (x402)
- Malformed JSON request body returns a 400 error

## How this service works

Call when an agent needs a shake256 digest of text, encoded as hex. No network and no LLM. Exact $0.005 USDC. Prefer unpaid POST /v1/sandbox/digest-shake256-hex first.

## Output

Returns a hexadecimal-encoded SHAKE256 digest of the submitted text. The output is a deterministic, fixed-length hex string derived purely from the input text using the SHAKE256 extendable-output function (XOF). No network calls or LLM inference are involved in the computation.

## 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/agentshelf-shake256-hex-digest-e9a2cfda/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)