# PennyRail Text Uppercase Converter

> PennyRail Text Uppercase Converter 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).

Converts an input string to uppercase text via a paid micro-transaction API endpoint

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/f/text.uppercase
- 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-text-uppercase-converter-d2f91b35
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_si99G8e8uYUBsULkWHxck

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-text-uppercase-converter-d2f91b35 -d '<json body>'
```

Example prompt: Can you uppercase the string 'hello world' using PennyRail's text converter?

## When to prefer this

Choose this endpoint when you need a simple, reliable, pay-per-call uppercase text transformation with no authentication setup and deterministic output. Best suited for lightweight agent workflows that need string normalization on demand without maintaining a service subscription.

## Known failure modes

- Missing 'input' field returns a validation error
- Non-string input may cause type errors or unexpected results
- Payment of 0.001 USDC must succeed via x402 protocol or the call is rejected
- Empty string input may return an empty result without error
- Network timeout on Vercel serverless cold start

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing the operation name (e.g. 'text.uppercase') and the result, which is the input string transformed to all uppercase characters.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "operation",
  "result"
 ],
 "properties": {
  "result": {},
  "operation": {
   "type": "string"
  }
 },
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-text-uppercase-converter-d2f91b35/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)