---
title: "MiniMax H3 Recast"
description: "MiniMax H3 Recast replaces the main people in a source video with new people from reference photos. The output keeps the motion, the gestures, the camera, the shot timing and the soundtrack of the source. The output length is the source length."
url: https://docs.roasos.com/models/video-edit/h3-max-recast
---

# MiniMax H3 Recast

<Callout>
  Family 

  `video-edit`

   · model 

  `h3-max-recast`

   · catalog 

  `model-catalog@2026-10-06.v5`

   · pricing 

  `customer-pricing@2026-11-05.v15`

  .
</Callout>

## Endpoint

```http
POST https://api.roasos.com/v1/video-edit/h3-max-recast
```

Send your API key as a bearer token. The key needs the scope `api:write`. Every paid request also needs an `Idempotency-Key` header.

The envelope fields `quote_only`, `quote_id`, `webhook_url` and `wait_timeout_seconds` behave the same on each model endpoint. Refer to [Jobs](/concepts/jobs) and [Quotes and credits](/concepts/quotes-and-credits).

## Good at

Put your own cast into an ad that works. Send `video_url` (5 to 30 seconds, MP4, no single shot longer than 15 seconds) and 1 to 4 new people. Send one photo for each person in `references`. An `avatar_id` adds one person: the front portrait of the saved avatar. The new people replace the main people of the source from left to right, in this order: your references, then the avatar. Each new person is in every shot where the original person is.

## Pricing

The unit is one **source\_second**. Pricing key: `h3-max-recast`.

| Request            | Credits |
| ------------------ | ------- |
| `5s_source_768p`   | 18      |
| `5s_source_1080p`  | 27      |
| `10s_source_768p`  | 36      |
| `10s_source_1080p` | 54      |
| `30s_source_768p`  | 108     |
| `30s_source_1080p` | 162     |

The credits come from the roasOS pricing table. No other field changes the price. To get the exact price of your request, send it with `quote_only: true` first.

## Modes

* `edit`

Provider endpoints: `minimax/h3-max/recast`.

## Request fields

| Field                  | Type      | Required | Default | Rule                          |
| ---------------------- | --------- | -------- | ------- | ----------------------------- |
| `avatar_id`            | string    | no       | —       | UUID                          |
| `enhance_realism`      | boolean   | no       | `false` | —                             |
| `prompt`               | string    | no       | —       | ≤ 10,000 characters           |
| `quote_id`             | string    | no       | —       | UUID                          |
| `quote_only`           | boolean   | no       | `false` | —                             |
| `references`           | string\[] | no       | —       | ≤ 4 items                     |
| `resolution`           | enum      | no       | `1080p` | `768p`, `1080p`               |
| `seed`                 | integer   | no       | —       | 0–2147483647                  |
| `video_url`            | string    | yes      | —       | https URL; ≤ 4,096 characters |
| `wait_timeout_seconds` | integer   | no       | `0`     | 0–60                          |
| `webhook_url`          | string    | no       | —       | https URL; ≤ 4,096 characters |

The schema is strict. A field that is not in this table gets `400 unsupported_option`. The field names are the roasOS role names. One role has one name in every family.

## Media

This endpoint accepts these media roles:

* `avatar_id` — identity; the saved character reference sheet, with a derived portrait only where the model requires a single face or source frame
* `references` — style and appearance references
* `video_url` — the source video

| Role         | Items | Maximum size | Content types                           | Duration |
| ------------ | ----- | ------------ | --------------------------------------- | -------- |
| `references` | ≤ 4   | 10 MB        | `image/jpeg`, `image/png`, `image/webp` | —        |
| `video_url`  | ≤ 1   | 100 MB       | `video/mp4`                             | 5–30 s   |

Every other role is refused: `elements`, `product_id`, `product_images`, `reference_images`, `image_url`, `end_image_url`, `scene_id`, `scene_image`, `video_urls`, `audio_urls`, `audio_url`, `voice_id`. A refused role gets `400 unsupported_option`.

<Callout>
  Each media URL must be an immutable object on 

  `https://cdn.roasos.com`

   that your workspace owns. Any other URL gets 

  `400 reference_media_not_workspace_owned`

  . Refer to 

  [Reference media and uploads](/concepts/reference-media)

   to learn how to put a file there.
</Callout>

## Prompt

Limit 10,000 characters. The prompt is optional.

* Use it to say who becomes whom: "The woman on the left becomes the person in the second photo."
* Use it to say what else must stay or change: "Keep her red jacket."
* Do not ask for a new shot, a new camera move or a different length.

## Not exposed

These catalog entries describe omitted inputs, pinned values and source constraints. They do not imply that the provider accepts every listed field.

* `enable_safety_checker` — pinned to `provider default (on); never sent`.
* `duration_seconds` — pinned to `the output follows the source clip`.
* `aspect_ratio` — pinned to `the output keeps the source framing`.
* `generate_audio` — pinned to `the output keeps the source sound`.
* `negative_prompt` — not accepted by this public endpoint.

## Result

The result kind is `video`. Always present: `url`.

```json
{
  "data": {
    "id": "gen_…",
    "kind": "video",
    "model": "h3-max-recast",
    "status": "completed",
    "result": {
      "url": "https://cdn.roasos.com/workspaces/ws_01/result"
    }
  }
}
```

The files are immutable objects on `https://cdn.roasos.com`. A result URL is a valid media input for your next request.

## Example

The three steps are always the same: quote, run, poll.

<CodeBlockTabs defaultValue="cURL">
  <CodeBlockTabsList>
    <CodeBlockTabsTrigger value="cURL">
      cURL
    </CodeBlockTabsTrigger>

    <CodeBlockTabsTrigger value="JavaScript">
      JavaScript
    </CodeBlockTabsTrigger>

    <CodeBlockTabsTrigger value="Python">
      Python
    </CodeBlockTabsTrigger>
  </CodeBlockTabsList>

  <CodeBlockTab value="cURL">
    ```bash
    # 1. Quote. Nothing is spent.
    curl -X POST https://api.roasos.com/v1/video-edit/h3-max-recast \
      -H "Authorization: Bearer roasos_sk_live_..." \
      -H "Idempotency-Key: 0f1c9e2a-h3-max-recast-0001" \
      -H "Content-Type: application/json" \
      -d '{"quote_only":true,"video_url":"https://cdn.roasos.com/workspaces/ws_01/uploads/video_url.mp4"}'
    # 200 { "data": { "kind": "quote", "quote_id": "q_7Hk...", "credits": 18, "expires_at": "...",
    #        "confirmation": { "model": "h3-max-recast", "example": "5s_source_768p" } } }

    # 2. Run. Same body, same Idempotency-Key, quote_id in place of quote_only.
    curl -X POST https://api.roasos.com/v1/video-edit/h3-max-recast \
      -H "Authorization: Bearer roasos_sk_live_..." \
      -H "Idempotency-Key: 0f1c9e2a-h3-max-recast-0001" \
      -H "Content-Type: application/json" \
      -d '{"quote_id":"q_7Hk...","video_url":"https://cdn.roasos.com/workspaces/ws_01/uploads/video_url.mp4"}'
    # 201 { "data": { "id": "gen_...", "status": "queued", "credits_reserved": 18 } }

    # 3. Poll, then read the result.
    curl https://api.roasos.com/v1/jobs/gen_.../status -H "Authorization: Bearer roasos_sk_live_..."
    curl https://api.roasos.com/v1/jobs/gen_.../result -H "Authorization: Bearer roasos_sk_live_..."
    ```
  </CodeBlockTab>

  <CodeBlockTab value="JavaScript">
    ```javascript
    const key = process.env.ROASOS_API_KEY;
    const url = "https://api.roasos.com/v1/video-edit/h3-max-recast";
    const idempotencyKey = "0f1c9e2a-h3-max-recast-0001";
    const input = {
      "video_url": "https://cdn.roasos.com/workspaces/ws_01/uploads/video_url.mp4"
    };

    const post = (payload) =>
      fetch(url, {
        method: "POST",
        headers: {
          Authorization: `Bearer ${key}`,
          "Idempotency-Key": idempotencyKey,
          "Content-Type": "application/json",
        },
        body: JSON.stringify(payload),
      }).then((response) => response.json());

    // 1. Quote. Nothing is spent.
    const quote = await post({ quote_only: true, ...input });
    console.log(quote.data.credits);

    // 2. Run.
    const job = await post({ quote_id: quote.data.quote_id, ...input });

    // 3. Poll, then read the result.
    let status = "queued";
    while (status !== "completed" && status !== "failed" && status !== "canceled") {
      await new Promise((done) => setTimeout(done, 3000));
      const poll = await fetch(`${url.split("/v1")[0]}/v1/jobs/${job.data.id}/status`, {
        headers: { Authorization: `Bearer ${key}` },
      }).then((response) => response.json());
      status = poll.data.status;
    }

    const result = await fetch(`${url.split("/v1")[0]}/v1/jobs/${job.data.id}/result`, {
      headers: { Authorization: `Bearer ${key}` },
    }).then((response) => response.json());
    console.log(result.data.result);
    ```
  </CodeBlockTab>

  <CodeBlockTab value="Python">
    ```python
    import os, time, requests

    key = os.environ["ROASOS_API_KEY"]
    url = "https://api.roasos.com/v1/video-edit/h3-max-recast"
    headers = {
        "Authorization": f"Bearer {key}",
        "Idempotency-Key": "0f1c9e2a-h3-max-recast-0001",
    }
    payload = {
        "video_url": "https://cdn.roasos.com/workspaces/ws_01/uploads/video_url.mp4"
    }

    # 1. Quote. Nothing is spent.
    quote = requests.post(url, headers=headers, json={"quote_only": True, **payload}).json()
    print(quote["data"]["credits"])

    # 2. Run.
    job = requests.post(url, headers=headers, json={"quote_id": quote["data"]["quote_id"], **payload}).json()
    job_id = job["data"]["id"]

    # 3. Poll, then read the result.
    jobs = "https://api.roasos.com/v1/jobs"
    status = "queued"
    while status not in ("completed", "failed", "canceled"):
        time.sleep(3)
        status = requests.get(f"{jobs}/{job_id}/status", headers=headers).json()["data"]["status"]

    result = requests.get(f"{jobs}/{job_id}/result", headers=headers).json()
    print(result["data"]["result"])
    ```
  </CodeBlockTab>
</CodeBlockTabs>

## Today

`POST /v1/video-edit/h3-max-recast` with `video_url`, `references`, `avatar_id`, `prompt`, `resolution` (768p|1080p, default 1080p), `enhance_realism` (more natural skin and better blending, off by default) and `seed`.

## See also

* [`llms.txt` for this model](https://docs.roasos.com/models/video-edit/h3-max-recast/llms.txt) — the same facts as one plain-text file for an agent.
* `GET https://api.roasos.com/v1/catalog/h3-max-recast` — the machine-readable form: enums, defaults, limits and prices. Refer to the [API reference](/api-reference/overview).
* [Jobs](/concepts/jobs) — how to poll a job and read its result.
* Provider endpoints: `minimax/h3-max/recast`.