# StableTube API

Base URL: `https://stabletube.dev`

YouTube downloads as an x402 API. POST a YouTube URL, get back a direct
`*.googlevideo.com` CDN download URL. The URL is short-lived (~6 hours).
There is no history, no SIWX, no free re-resolve — if the URL expires, repay.

## Workflow

```
1. Optional: GET /api/info?url=...   # free metadata + available qualities
2. POST     /api/download             # paid; returns direct downloadUrl
3. Consume  downloadUrl within ~6h    # plain HTTP GET / curl
```

## Endpoints

- `GET  /api/info?url=...` — free. Title, duration, channel, thumbnails, `availableQualities`.
- `POST /api/download` — paid. Body: `url`, `quality` (`360p` | `720p` | `1080p`, default `720p`), `format` (`mp4`). Returns `downloadUrl`, `mimeType`, `contentLengthBytes`, `expiresAt`.

## Quality fallback

If the requested `quality` isn't available for that video, the closest lower quality is returned and reflected in the response `quality` field. If no mp4 stream exists at all, the call aborts with 404 inside the `.paid()` pricing function — you are not charged.

## Pricing

Floor $0.02. flat per-quality: 360p $0.02 / 720p $0.04 / 1080p $0.08.

See `/openapi.json` for full request/response schemas.