# PennyRail SHA-256 Hash Endpoint

> PennyRail SHA-256 Hash Endpoint is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Computes a SHA-256 cryptographic hash of a given input string, delivered as a paid micro-service via x402 settlement.

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/crypto.sha256--sha-256
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-sha-256-hash-endpoint-06cf0dac
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2SRkNJrc1P37fV4-BN-U1

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 pennyrail-sha-256-hash-endpoint-06cf0dac -d '<json body>'
```

Example prompt: Can you hash the string 'hello world' using SHA-256 and give me the digest?

## When to prefer this

Choose this endpoint when you need a simple, pay-per-call SHA-256 hash computation without setting up local crypto libraries, or when operating inside an agent workflow that already uses x402 micro-payment infrastructure. It is ideal for lightweight, stateless hashing tasks where integrating a full cryptography dependency is undesirable. Avoid it for bulk hashing operations where per-call cost would accumulate significantly.

## Known failure modes

- Missing 'input' field in request body returns a validation error
- Non-string input type may cause schema rejection
- Payment failure via x402 protocol results in 402 Payment Required before computation occurs
- Empty string input is accepted but produces a known fixed hash
- Network timeout on Vercel cold start may cause delayed response

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing the SHA-256 hex digest of the provided input string. The response schema is open (additionalProperties: true), so the hash value is returned alongside any metadata fields the service includes.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-sha-256-hash-endpoint-06cf0dac/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pennyrail.vercel.app](https://www.zero.xyz/host/pennyrail.vercel.app/llms.txt)