# Nihongo Refine API

> Nihongo Refine API is a paid API for AI agents from x402-stall.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Rewrites awkward or machine-translated Japanese text into natural written Japanese with tone control

## Facts

- Endpoint: POST https://x402-stall.onrender.com/refine
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/nihongo-refine-api-d6faa03a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NjA82R5E-19LmjiQPdyCP

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 nihongo-refine-api-d6faa03a -d '<json body>'
```

Example prompt: Can you rewrite this Japanese text so it sounds natural and professional — it's from a machine translation and reads a bit stiff: 「彼はミーティングを持つ予定です。」Use a business tone.

## When to prefer this

Choose this endpoint when you need to improve the naturalness of Japanese text that was machine-translated or written by a non-native speaker, especially when you need tone control (business, casual, or neutral). It is ideal for localization pipelines, email drafting, app UI copy review, and social content polish. Prefer it over generic translation APIs when the source is already in Japanese and the goal is fluency improvement rather than cross-language translation.

## Known failure modes

- Input text exceeds 2000 character limit — request rejected
- Invalid tone value outside accepted enum (business, casual, neutral)
- Non-Japanese or empty text submitted — output may be undefined
- Network timeout from the Render.com host during cold start
- Payment failure via x402 protocol causes 402 response before processing
- Highly idiomatic or dialectal input may produce inconsistent refinements

## How this service works

Pay-per-call API that rewrites awkward or machine-translated Japanese into natural written Japanese.

## Output

A JSON object containing a 'refined' field with the rewritten natural Japanese text, and a 'notes' array listing specific substitutions made (e.g. which unnatural phrases were replaced and with what), allowing the caller to understand what was changed and why.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "description": "Japanese text to refine (max 2000 chars)"
  },
  "tone": {
   "type": "string",
   "description": "business | casual | neutral"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "notes": [
   "「ミーティングを持つ」→「会議を行う」"
  ],
  "refined": "彼は会議を行いました。"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/nihongo-refine-api-d6faa03a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-stall.onrender.com](https://www.zero.xyz/host/x402-stall.onrender.com/llms.txt)