# Syntexa AgentShelf Fletcher32 Checksum (Decimal)

> Syntexa AgentShelf Fletcher32 Checksum (Decimal) is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.008/call, status unknown (last checked 2026-10-02).

Computes a Fletcher-32 checksum of the provided text and returns it as a decimal integer

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/checksum-fletcher32-dec?utm_source=zero.xyz
- Price: $0.008/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/syntexa-agentshelf-fletcher32-checksum-decimal-2f0a8444
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mcHmBOrVak2f1UP09XeRR

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 syntexa-agentshelf-fletcher32-checksum-decimal-2f0a8444 -d '<json body>'
```

Example prompt: Can you compute the Fletcher-32 checksum of the text 'Hello, world! This is a test string.' and give me the result as a decimal number?

## When to prefer this

Choose this endpoint when you need a deterministic Fletcher-32 checksum returned as a decimal integer and cannot or prefer not to compute it locally. Prefer the free sandbox endpoint (POST /v1/sandbox/checksum-fletcher32-dec) first for testing. Use this paid endpoint in production agentic pipelines where checksum computation needs to be outsourced reliably at $0.008 USDC per call.

## Known failure modes

- Empty or missing text field returns a validation error
- Text exceeding 100,000 characters is rejected
- Missing or invalid API key returns an authentication error
- Malformed JSON body returns a 400 bad request
- Payment not completed (x402) results in a 402 Payment Required response

## How this service works

Call when an agent needs a fletcher32 checksum of text as dec. No network and no LLM. Exact $0.008 USDC. Prefer unpaid POST /v1/sandbox/checksum-fletcher32-dec first.

## Output

Returns a Fletcher-32 checksum value as a decimal integer, computed purely server-side without any network calls or LLM inference. The result is deterministic and reproducible for the same input text.

## 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/syntexa-agentshelf-fletcher32-checksum-decimal-2f0a8444/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)