# LTX 2.5 Fast

> Speed-optimized 2.5 with synchronized native audio — up to 4K, up to 20s, with camera motion control.

## Overview

- **Model ID**: `ltx-v2.5-fast`
- **Workflow**: `lightricks/ltx-2.5/text-to-video/fast`
- **Provider**: LTX
- **Category**: Text → Video (video)
- **Output**: A video URL.
- **Tags**: image input, start frame, end frame, fast, up to 20s, audio, 4k, camera motion
- **Unified endpoint**: `POST https://api.picsart.com/workflows/v1/models/execute` (model id in the body)
- **Compatibility endpoint**: `POST https://api.picsart.com/workflows/lightricks/ltx-2.5/text-to-video/fast/execute` (vendor's own parameters)
- **Execution**: long-running — use the async submit/poll pair or the SDK, which polls for you
- **Model page**: https://picsart.com/api-platform/models/ltx-v2.5-fast

## Pricing

Rates are in USD. Every row below is an exact rate for the settings it names — the columns are the settings that change the price for this model. Every response reports what was actually charged in `response.usage.credits`.

| Tier | Rate |
| --- | --- |
| 720p | $0.099 / sec |
| 1080p | $0.143 / sec |
| 1440p | $0.209 / sec |
| 2160p | $0.33 / sec |

Published rates. Volume pricing, invoicing and annual agreements: https://picsart.com/api-platform/contact-sales

## Authentication

The SDK and the REST API authenticate with a Picsart API key sent as a bearer token. Create a key in the console at https://picsart.com/api-platform/dashboard/api-keys, keep it in a server-side environment variable, and never ship it in browser code or commit it.

```bash
export PICSART_API_KEY="YOUR_KEY"
```

```http
Authorization: Bearer $PICSART_API_KEY
```

The CLI and the MCP server do not use an API key: `gen-ai login` signs in through the browser once per machine and stores a token locally.

## Interfaces

- **SDK** — `@picsart/ai-sdk` (TypeScript, Node 20+, ESM). Type-safe `ai.generate()` / `ai.generateText()` with per-model parameter types; polls long jobs for you.
- **REST** — the API gateway at `https://api.picsart.com`. Sync `/execute`, or async `/submit` + `/{taskId}/result`.
- **CLI** — `@picsart/gen-ai` (`gen-ai`). Generate from a terminal, quote cost before spending, emit JSON for pipelines.
- **MCP** — the same models inside Claude Code, Cursor, Windsurf and other MCP hosts. Setup: https://picsart.com/gen-ai-mcp/

```bash
npm install @picsart/ai-sdk      # SDK
npm install -g @picsart/gen-ai   # CLI (also drives the MCP server)
```

## Unified API (recommended)

One parameter set, used by the SDK and by REST alike: the names below are what `ai.generate('ltx-v2.5-fast', …)` takes, and what goes inside the inner `params` of a REST call. Over REST the model id travels in the body, not the path — one workflow, `v1/models`, fronts the whole catalogue.

### Execution modes

- **Sync** — `POST /workflows/v1/models/execute` returns the result in one call. Only for jobs that finish within ~20 seconds; otherwise it times out.
- **Async** — `POST /workflows/v1/models/submit` returns a task id; poll `GET /workflows/v1/models/{taskId}/result` until `response.status` is `COMPLETED` or `FAILED`. Task statuses: `ACCEPTED` · `IN_PROGRESS` · `COMPLETED` · `FAILED`.
- **SDK** — `ai.generate()` always awaits the finished result; polling is hidden.

Video jobs routinely outrun the sync limit: use async over REST, or the SDK, which polls for you.

### Input parameters

- **`prompt`** (`string`, _required_): Prompt
  - Max length: 5000 characters
- **`duration`** (`number`, _optional_)
  - Default: `6`
  - Options: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`
- **`resolution`** (`string`, _optional_)
  - Default: `"1080p"`
  - Options: `720p`, `1080p`, `1440p`, `2160p`
- **`aspectRatio`** (`string`, _optional_)
  - Default: `"16:9"`
  - Options: `16:9`, `9:16`
- **`fps`** (`number`, _optional_): FPS
  - Default: `25`
  - Options: `24`, `25`, `48`, `50`
- **`cameraMotion`** (`string`, _optional_): Camera Motion
  - Default: `"none"`
  - Options: `none`, `static`, `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `focus_shift`
- **`generateAudio`** (`boolean`, _optional_)
  - Default: `true`
- **`startFrame`** (`string`, _optional_): Start Frame
  - Accepts: image URL
- **`endFrame`** (`string`, _optional_): End Frame
  - Accepts: image URL

### Input JSON Schema

The inner `params` object. Over REST it is wrapped as `{ "params": { "model": "<id>", "params": <this> } }`; the SDK takes it directly.

```json
{
  "type": "object",
  "required": [
    "prompt"
  ],
  "properties": {
    "prompt": {
      "type": "string",
      "maxLength": 5000,
      "description": "Prompt"
    },
    "duration": {
      "type": "number",
      "enum": [
        6,
        8,
        10,
        12,
        14,
        16,
        18,
        20
      ],
      "default": 6
    },
    "resolution": {
      "type": "string",
      "enum": [
        "720p",
        "1080p",
        "1440p",
        "2160p"
      ],
      "default": "1080p"
    },
    "aspectRatio": {
      "type": "string",
      "enum": [
        "16:9",
        "9:16"
      ],
      "default": "16:9"
    },
    "fps": {
      "type": "number",
      "enum": [
        24,
        25,
        48,
        50
      ],
      "default": 25,
      "description": "FPS"
    },
    "cameraMotion": {
      "type": "string",
      "enum": [
        "none",
        "static",
        "dolly_in",
        "dolly_out",
        "dolly_left",
        "dolly_right",
        "jib_up",
        "jib_down",
        "focus_shift"
      ],
      "default": "none",
      "description": "Camera Motion"
    },
    "generateAudio": {
      "type": "boolean",
      "default": true
    },
    "startFrame": {
      "type": "string",
      "format": "uri",
      "description": "Start Frame"
    },
    "endFrame": {
      "type": "string",
      "format": "uri",
      "description": "End Frame"
    }
  },
  "additionalProperties": false
}
```

### Required parameters example

The required parameters plus the defaults that shape the output, as a REST body:

```json
{
  "params": {
    "model": "ltx-v2.5-fast",
    "params": {
      "prompt": "A serene mountain lake at golden hour, ultra detailed",
      "duration": 6,
      "resolution": "1080p",
      "aspectRatio": "16:9"
    }
  }
}
```

### Response

The body is the gateway's status envelope: the output is at `response.result`, next to the task id, its status and the credits charged. Asset models return `url` plus an `items` array of results.

```json
{
  "status": "success",
  "response": {
    "id": "task_abc123",
    "status": "COMPLETED",
    "result": {
      "url": "https://cdn.picsart.com/…/result",
      "items": [
        {
          "url": "https://cdn.picsart.com/…/result"
        }
      ],
      "model": "ltx-v2.5-fast"
    }
  }
}
```

What `ai.generate()` / `ai.generateText()` resolve to (the envelope already unwrapped):

```json
{
  "items": [
    {
      "url": "https://cdn.picsart.com/…/result"
    }
  ],
  "model": "ltx-v2.5-fast"
}
```

### Usage examples

#### TypeScript (SDK)

```typescript
import { createClient } from '@picsart/ai-sdk';

const ai = createClient({
  apiKey: process.env.PICSART_API_KEY,
  apiUrl: 'https://api.picsart.com',
});

const result = await ai.generate('ltx-v2.5-fast', {
  prompt: "A serene mountain lake at golden hour, ultra detailed",
  duration: 6,
  resolution: "1080p",
  aspectRatio: "16:9"
});

console.log(result.url); // video URL
```

#### cURL (sync)

```bash
curl -X POST 'https://api.picsart.com/workflows/v1/models/execute' \
  -H 'Authorization: Bearer $PICSART_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
  "params": {
    "model": "ltx-v2.5-fast",
    "params": {
      "prompt": "A serene mountain lake at golden hour, ultra detailed",
      "duration": 6,
      "resolution": "1080p",
      "aspectRatio": "16:9"
    }
  }
}'
```

#### cURL (async: submit, then poll)

```bash
# 1. Submit the job
curl -X POST 'https://api.picsart.com/workflows/v1/models/submit' \
  -H 'Authorization: Bearer $PICSART_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
  "params": {
    "model": "ltx-v2.5-fast",
    "params": {
      "prompt": "A serene mountain lake at golden hour, ultra detailed",
      "duration": 6,
      "resolution": "1080p",
      "aspectRatio": "16:9"
    }
  }
}'
# → { "status": "success", "response": { "id": "task_abc123" } }

# 2. Poll until response.status is COMPLETED
curl 'https://api.picsart.com/workflows/v1/models/task_abc123/result' \
  -H 'Authorization: Bearer $PICSART_API_KEY'
```

#### CLI

```bash
gen-ai login  # once per machine
gen-ai models info ltx-v2.5-fast  # this model's parameters
gen-ai pricing ltx-v2.5-fast  # quote before spending credits
gen-ai generate -m ltx-v2.5-fast \
  -p "A serene mountain lake at golden hour" \
  -d 6 \
  --ar 16:9
```

## Compatibility API (vendor parameters)

Alongside the unified API, the `lightricks/ltx-2.5/text-to-video/fast` workflow takes LTX's own parameters exactly as the vendor defines them — nothing renamed or reshaped. It is the shortest path onto Picsart for request bodies already written against the vendor; the trade is that a request is written for one vendor, and the result comes back in the vendor's own shape. Same authentication.

- **Endpoint**: `POST https://api.picsart.com/workflows/lightricks/ltx-2.5/text-to-video/fast/execute` (sync) · `POST …/submit` + `GET …/{taskId}/result` (async)
- **SDK**: `ai.apis.run('lightricks/ltx-2.5/text-to-video/fast', params, { mode })` — params forwarded verbatim

### Vendor parameters

| Parameter | Type | Required | Default | Details |
| --- | --- | --- | --- | --- |
| `aspect_ratio` | `string` | no | `16:9` | The aspect ratio of the generated video · Options: `16:9`, `9:16` |
| `camera_motion` | `string` | no | — | Optional camera motion applied to the generated video. · Options: `dolly_in`, `dolly_out`, `dolly_left`, `dolly_right`, `jib_up`, `jib_down`, `static`, `focus_shift` |
| `generate_audio` | `boolean` | no | `true` | Whether to generate audio for the generated video |
| `fps` | `integer` | no | `25` | The frames per second of the generated video. · Options: `24`, `25`, `48`, `50` |
| `duration` | `object` | no | `auto` | The duration of the generated video in seconds. At 720p and 1080p, 24 or 25 FPS supports up to 20 seconds, while 48 or 50 FPS supports up to 10 seconds. At 1440p and 2160p, all frame rates support up to 10 seconds. Set to 'auto' to let the model choose the duration automatically. · Options: `6`, `8`, `10`, `12`, `14`, `16`, `18`, `20`, `auto` |
| `prompt` | `string` | yes | — | The prompt to use for the generated video · 1–5000 chars · e.g. `Through-the-veil shot of a bride's face during an Indian wedding ceremony, camera positioned behind the sheer red dupatta fabric, the embroidered pattern creating a textured overlay on her face, her eyes lined with kohl looking down at henna-covered hands, marigold garlands in soft background bokeh, 85mm f/1.2 focused through the fabric layer, warm tungsten and candlelight, Mira Nair Monsoon Wedding intimacy` |
| `resolution` | `string` | no | `1080p` | The resolution of the generated video. · Options: `720p`, `1080p`, `1440p`, `2160p` |
| `options` | `object` | no | — | Platform-specific options for safety checks and Picsart Drive integration. |
| └ `safety_checks` | `object` | no | — | Safety check configuration. |
| └   `enabled` | `boolean` | no | `true` | Enable or disable text safety checks. Defaults to true. |
| └ `drive` | `object` | no | — | Picsart Drive storage options. When provided, the result will be saved to the user's Drive. |
| └   `name` | `string` | yes | — | Filename to save the result as in Picsart Drive. |
| └   `attributes` | `object` | no | — | Additional file metadata attributes. |
| └   `folder` | `object` | no | — | Destination folder in Picsart Drive. |

### Example request body

```json
{
  "params": {
    "prompt": "Through-the-veil shot of a bride's face during an Indian wedding ceremony, camera positioned behind the sheer red dupatta fabric, the embroidered pattern creating a textured overlay on her face, her eyes lined with kohl looking down at henna-covered hands, marigold garlands in soft background bokeh, 85mm f/1.2 focused through the fabric layer, warm tungsten and candlelight, Mira Nair Monsoon Wedding intimacy"
  }
}
```

### Usage examples

#### TypeScript (`ai.apis.run`)

```typescript
import { createClient, ApiRunMode } from '@picsart/ai-sdk';

const ai = createClient({
  apiKey: process.env.PICSART_API_KEY,
  apiUrl: 'https://api.picsart.com',
});

// Calls the 'lightricks/ltx-2.5/text-to-video/fast' workflow directly — params are sent as-is.
const { result, usage } = await ai.apis.run('lightricks/ltx-2.5/text-to-video/fast', {
  prompt: "Through-the-veil shot of a bride's face during an Indian wedding ceremony, camera positioned behind the sheer red dupatta fabric, the embroidered pattern creating a textured overlay on her face, her eyes lined with kohl looking down at henna-covered hands, marigold garlands in soft background bokeh, 85mm f/1.2 focused through the fabric layer, warm tungsten and candlelight, Mira Nair Monsoon Wedding intimacy"
}, {
  mode: ApiRunMode.SYNC,
});

console.log(result); // workflow-specific output
console.log(usage?.credits); // amount charged, in $
```

#### cURL (sync)

```bash
curl -X POST 'https://api.picsart.com/workflows/lightricks/ltx-2.5/text-to-video/fast/execute' \
  -H 'Authorization: Bearer $PICSART_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
  "params": {
    "prompt": "Through-the-veil shot of a bride's face during an Indian wedding ceremony, camera positioned behind the sheer red dupatta fabric, the embroidered pattern creating a textured overlay on her face, her eyes lined with kohl looking down at henna-covered hands, marigold garlands in soft background bokeh, 85mm f/1.2 focused through the fabric layer, warm tungsten and candlelight, Mira Nair Monsoon Wedding intimacy"
  }
}'
```

#### cURL (async: submit, then poll)

```bash
# 1. Submit the job
curl -X POST 'https://api.picsart.com/workflows/lightricks/ltx-2.5/text-to-video/fast/submit' \
  -H 'Authorization: Bearer $PICSART_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
  "params": {
    "prompt": "Through-the-veil shot of a bride's face during an Indian wedding ceremony, camera positioned behind the sheer red dupatta fabric, the embroidered pattern creating a textured overlay on her face, her eyes lined with kohl looking down at henna-covered hands, marigold garlands in soft background bokeh, 85mm f/1.2 focused through the fabric layer, warm tungsten and candlelight, Mira Nair Monsoon Wedding intimacy"
  }
}'
# → { "status": "success", "response": { "id": "wf_abc123" } }

# 2. Poll until response.status is COMPLETED
curl 'https://api.picsart.com/workflows/lightricks/ltx-2.5/text-to-video/fast/wf_abc123/result' \
  -H 'Authorization: Bearer $PICSART_API_KEY'
```

### Response

Over HTTP the vendor-shaped result arrives inside the gateway envelope at `response.result`:

```json
{
  "status": "success",
  "response": {
    "id": "wf_abc123",
    "status": "COMPLETED",
    "result": {
      "video": {
        "num_frames": 0,
        "file_name": "z9RV14K95DvU.png",
        "fps": 0,
        "duration": 0,
        "file_size": 4404019,
        "url": "https://cdn.picsart.com/…/result.mp4",
        "height": 0,
        "width": 0,
        "content_type": "image/png"
      }
    }
  }
}
```

`ai.apis.run()` unwraps that envelope and resolves to `{ result, usage }`:

```json
{
  "result": {
    "video": {
      "num_frames": 0,
      "file_name": "z9RV14K95DvU.png",
      "fps": 0,
      "duration": 0,
      "file_size": 4404019,
      "url": "https://cdn.picsart.com/…/result.mp4",
      "height": 0,
      "width": 0,
      "content_type": "image/png"
    }
  }
}
```

## Additional resources

- Model page: https://picsart.com/api-platform/models/ltx-v2.5-fast
- Try it: https://picsart.com/api-platform/models/ltx-v2.5-fast/playground
- SDK: https://picsart.com/api-platform/models/ltx-v2.5-fast/sdk
- REST API (unified): https://picsart.com/api-platform/models/ltx-v2.5-fast/api
- Compatibility API (vendor parameters): https://picsart.com/api-platform/models/ltx-v2.5-fast/advanced
- Pricing: https://picsart.com/api-platform/models/ltx-v2.5-fast/pricing
- This document: https://picsart.com/api-platform/models/ltx-v2.5-fast/llms.txt
- All models: https://picsart.com/api-platform/models
- Docs — quickstart https://picsart.com/api-platform/docs/quickstart, authentication https://picsart.com/api-platform/docs/authentication, SDK https://picsart.com/api-platform/docs/sdk, REST https://picsart.com/api-platform/docs/api-reference, CLI https://picsart.com/api-platform/docs/cli, MCP https://picsart.com/api-platform/docs/mcp
- CLI reference: https://picsart.github.io/picsart-mcp-cli-docs/guide/introduction