# PennyRail Hex Decode

> PennyRail Hex Decode is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Decodes a hexadecimal-encoded string back into its original plaintext representation

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/encoding.hex-decode--hex-decode
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-hex-decode-2290f6f2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kOPJFmnQDysHHYJ0zMGrF

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-hex-decode-2290f6f2 -d '<json body>'
```

Example prompt: Can you decode this hex string for me: 48656c6c6f20576f726c64 — I need to know what the original text says.

## When to prefer this

Use this endpoint when you need a simple, pay-per-call hex decoding operation without standing up your own infrastructure. Ideal for agents that occasionally encounter hex-encoded data and need to decode it on demand without embedding a local utility.

## Known failure modes

- Invalid hex string (odd number of characters or non-hex characters) returns an error
- Empty input string may return an error or empty result
- Non-string input fails schema validation
- Payment failure (HTTP 402) if USDC balance insufficient

## How this service works

Machine-readable settlement service

## Output

Returns an object containing the decoded result of the provided hex-encoded input string, revealing the original plaintext or binary content that was hex-encoded.

## 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-hex-decode-2290f6f2/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)