> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stirvid.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Video Generation

> Quality tiers, duration limits, sound, and storage.

## Quality tiers

| Tier  | Use case                        |
| ----- | ------------------------------- |
| `std` | Fast previews, social clips.    |
| `pro` | Final renders, higher fidelity. |

## Durations

Output duration matches the input clip. Longer clips cost proportionally more credits. StirVid returns a **quote** before deducting credits; the quote reflects both mode and duration.

## Sound retention

* **Retain**: original audio is muxed into the output MP4 unchanged.
* **Silent**: no audio track written.

## Storage

* Rendered MP4s are archived to storage on completion.
* Signed URLs are issued on demand and expire on rotation.
* Job records persist even after the media is archived, so historical generations remain queryable through the Control API and MCP `generation_status`.