# ai-captions

> Add AI-generated animated captions to any video using Vadoo's caption engine. Supports multiple languages and viral caption themes like Hormozi style. Perfect for social media creators, marketers, and content producers.

## Overview

- **Endpoint**: `POST https://api.muapi.ai/api/v1/ai-captions`
- **Model ID**: `ai-captions`
- **Category**: video to video
- **Variant**: AI Captions
- **Family**: tools
- **Cost**: 0 credits per call (some models compute cost dynamically based on params)

## API Usage

MuApi uses a **submit-then-poll** pattern: submit a job, get a `request_id`, then poll the predictions endpoint until `status` is `completed`. Optionally pass `?webhook=YOUR_URL` on the submit call to receive a POST callback when the job finishes (skip polling).

**Authentication**: send your MuApi key in the `x-api-key` header. Get one at https://muapi.ai/access-keys.

### 1. Submit a job

```http
POST https://api.muapi.ai/api/v1/ai-captions
Content-Type: application/json
x-api-key: YOUR_API_KEY
```

**Minimum (required only):**

```json
{
  "video_url": "https://example.com/your-video_url"
}
```

**Full example (all params):**

```json
{
  "video_url": "https://example.com/your-video_url",
  "language": "English",
  "theme": "Hormozi_1"
}
```

**Response:**

```json
{
  "request_id": "abc123",
  "status": "processing"
}
```

### 2. Poll for the result

```http
GET https://api.muapi.ai/api/v1/predictions/{request_id}/result
x-api-key: YOUR_API_KEY
```

Possible `status` values: `queued`, `pending`, `processing`, `completed`, `failed`, `cancelled`. Poll every 2-5 seconds until terminal. When `completed`, the result URLs are in the `outputs` array.

**Example response when `completed`:**

```json
{
  "id": "abc123",
  "status": "completed",
  "outputs": [
    "https://cdn.muapi.ai/.../output.png"
  ],
  "urls": {
    "get": "https://api.muapi.ai/api/v1/predictions/abc123/result"
  },
  "created_at": "2026-05-08T12:34:56Z",
  "has_nsfw_contents": []
}
```

### cURL

```bash
# 1. Submit
REQUEST_ID=$(curl -s -X POST https://api.muapi.ai/api/v1/ai-captions \
  -H "x-api-key: $MUAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"video_url":"https://example.com/your-video_url"}' | jq -r .request_id)

# 2. Poll until completed
while :; do
  RESP=$(curl -s https://api.muapi.ai/api/v1/predictions/$REQUEST_ID/result -H "x-api-key: $MUAPI_API_KEY")
  STATUS=$(echo "$RESP" | jq -r .status)
  [ "$STATUS" = "completed" ] && echo "$RESP" | jq .outputs && break
  [ "$STATUS" = "failed" ] && echo "$RESP" && exit 1
  sleep 3
done
```

### Python

```python
import os, time, requests

API = "https://api.muapi.ai/api/v1"
headers = {"x-api-key": os.environ["MUAPI_API_KEY"]}

r = requests.post(f"{API}/ai-captions", headers=headers, json={"video_url":"https://example.com/your-video_url"})
request_id = r.json()["request_id"]

while True:
    res = requests.get(f"{API}/predictions/{request_id}/result", headers=headers).json()
    if res["status"] == "completed":
        print(res["outputs"]); break
    if res["status"] == "failed":
        raise RuntimeError(res.get("error")); 
    time.sleep(3)
```

## Input Schema

The API accepts the following input parameters:

- **`video_url`** (`string`, _required_):
  Public URL of the video to add captions to. Maximum 600MB or 10 minutes.

- **`language`** (`string`, _optional_):
  Language of the video audio for transcription.
  - Default: `"English"`
  - Options: `"English"`, `"English (USA)"`, `"English (UK)"`, `"English (Australia)"`, `"English (Canada)"`, `"Japanese"`, `"Chinese"`, `"German"`, `"Hindi"`, `"French"`, `"French (France)"`, `"French (Canada)"`, `"Korean"`, `"Portuguese (Brazil)"`, `"Portuguese (Portugal)"`, `"Portuguese"`, `"Spanish (Spain)"`, `"Spanish (Mexico)"`, `"Italian"`, `"Spanish"`, `"Indonesian"`, `"Dutch"`, `"Turkish"`, `"Filipino"`, `"Polish"`, `"Swedish"`, `"Bulgarian"`, `"Romanian"`, `"Arabic (Saudi Arabia)"`, `"Arabic (UAE)"`, `"Arabic"`, `"Czech"`, `"Greek"`, `"Finnish"`, `"Croatian"`, `"Malay"`, `"Slovak"`, `"Danish"`, `"Tamil"`, `"Telugu"`, `"Ukrainian"`, `"Russian"`, `"Hungarian"`, `"Norwegian"`, `"Vietnamese"`

- **`theme`** (`string`, _optional_):
  Visual style/theme for the captions. E.g. Hormozi_1, Hormozi_2.
  - Default: `"Hormozi_1"`
  - Options: `"Hormozi_1"`, `"Hormozi_2"`, `"Hormozi_3"`, `"Beast"`, `"Ali"`, `"Noah"`, `"Karl"`, `"Luke"`, `"Devin"`, `"Celine"`, `"Maya"`, `"Ella"`, `"Dan"`, `"David"`, `"Tracy"`, `"Umi"`, `"Iman"`, `"William"`

## Output Schema

The polling endpoint returns the following fields:

- **`id`** (`string`): The request ID.
- **`status`** (`string`): One of `queued`, `pending`, `processing`, `completed`, `failed`, `cancelled`.
- **`outputs`** (`array`): URLs to generated images/videos/audio. Empty until `status` is `completed`.
- **`urls.get`** (`string`): Self-link to re-fetch this prediction.
- **`error`** (`string` | `null`): Error message if `status` is `failed`.
- **`created_at`** (`string`): ISO-8601 timestamp of when the request was created.
- **`has_nsfw_contents`** (`array of boolean`): Per-output NSFW detection flags.

## Webhooks (optional)

Append `?webhook=https://your-server/path` to the submit URL. When the job reaches a terminal state, MuApi will POST the same shape as the polling response to your URL — no polling needed.

## Agent Integration

MuApi ships an MCP server and CLI so agents (Claude Code, Cursor, custom) can call this endpoint without writing HTTP code:

```bash
# Install the CLI
npm install -g muapi-cli

# Authenticate once
muapi auth login

# Expose all MuApi models as MCP tools to your agent
muapi mcp serve
```

The MCP server exposes tools that wrap submit + poll for every model, including `ai-captions`. See `muapi --help` for category-specific shortcuts (`muapi image generate`, `muapi video from-image`, etc.).

## Related Models
- [Image Faceswap](https://muapi.ai/playground/ai-image-face-swap)
- [Product Shot](https://muapi.ai/playground/ai-product-shot)
- [Image Upscaler](https://muapi.ai/playground/ai-image-upscaler)
- [Skin Enhancer](https://muapi.ai/playground/ai-skin-enhancer)
- [Product Photography](https://muapi.ai/playground/ai-product-photography)
- [Background Remover](https://muapi.ai/playground/ai-background-remover)
- [AI Captions](https://muapi.ai/playground/ai-captions)
- [Ghibli Style](https://muapi.ai/playground/ai-ghibli-style)
- [Anime Generator](https://muapi.ai/playground/ai-anime-generator)
- [Image Extension](https://muapi.ai/playground/ai-image-extension)
- [Object Eraser](https://muapi.ai/playground/ai-object-eraser)
- [Video Translate](https://muapi.ai/playground/heygen-video-translate)
- [Video Upscaler Pro](https://muapi.ai/playground/ai-video-upscaler-pro)
- [Watermark Remover](https://muapi.ai/playground/video-watermark-remover)
- [Dress Change](https://muapi.ai/playground/ai-dress-change)
- [Color Photo](https://muapi.ai/playground/ai-color-photo)
- [Video Faceswap](https://muapi.ai/playground/ai-video-face-swap)
- [Video Background Remover](https://muapi.ai/playground/video-background-remover)
- [Video Upscaler](https://muapi.ai/playground/ai-video-upscaler)
- [Remix Video](https://muapi.ai/playground/remix-video)

## Resources
- [Playground Page](https://muapi.ai/playground/ai-captions)
- [API Reference](https://muapi.ai/playground/ai-captions?tab=2)
- [Global llms.txt](https://muapi.ai/llms.txt)