runwayml

# Runway API Skill Generate AI videos, images, and audio using Runway's API. Features **Gen-4.5** — Runway's latest and most capable model — supporting both text-to-video and image-to-video generation, plus Gen-4 variants and third-party models from Google (Veo) and ElevenLabs. ## Setup 1. Get your API key from [dev.runwayml.com](https://dev.runwayml.com) 2. Store it as `RUNWAYML_API_SECRET` in your environment 3. Install the Node.js SDK: `npm install @runwayml/sdk` ## Quick Start ### Text-to-Video (gen4.5) ```javascript import RunwayML from "@runwayml/sdk"; const client = new RunwayML(); // reads RUNWAYML_API_SECRET automatically const task = await client.textToVideo.create({ model: "gen4.5", promptText: "A steaming bowl of noodles in a busy hawker centre, warm light, slow camera push-in", duration: 5, ratio: "1280:720" }).waitForTaskOutput(); console.log("Video URL:", task.output[0]); ``` ### Image-to-Video (gen4.5) ```javascript import RunwayML from "@runwayml/sdk"; import fs from "fs"; const client = new RunwayML(); const imageData = fs.readFileSync("product.jpg"); const promptImage = `data:image/jpeg;base64,${imageData.toString("base64")}`; const task = await client.imageToVideo.create({ model: "gen4.5", promptImage, promptText: "Slow dolly-in toward the product jar, warm side lighting, sauce shimmer visible through glass", duration: 5, ratio: "1280:720" }).waitForTaskOutput(); console.log("Video URL:", task.output[0]); ``` ### cURL (direct API) ```bash # Text-to-video curl -X POST "https://api.dev.runwayml.com/v1/image_to_video" \ -H "Authorization: Bearer $RUNWAYML_API_SECRET" \ -H "X-Runway-Version: 2024-11-06" \ -H "Content-Type: application/json" \ -d '{ "model": "gen4.5", "promptText": "A serene mountain landscape at sunset", "ratio": "1280:720", "duration": 5 }' ``` ## Available Models ### Video Generation | Model | Input | Credits/sec | Notes | |-------|-------|-------------|-------| | **`gen4.5`** ⭐ | Text or Image | 12 | **Newest & recommended** | | `gen4_turbo` | Image only | 5 | Fast I2V iteration | | `veo3.1` | Text or Image | 40 | Google Veo — includes audio | | `veo3.1_fast` | Text or Image | 15 | Veo — audio, cheaper | | `gen4_aleph` | Video + Text/Image | 15 | Video-to-video transformation | | `act_two` | Image or Video | 5 | Character performance/motion | ### Image Generation | Model | Credits | Notes | |-------|---------|-------| | `gen4_image` | 5–8/image | High quality, supports style references | | `gen4_image_turbo` | 2/image | Fast iteration (requires reference image) | ### Audio (ElevenLabs via Runway) | Model | Output | Credits | |-------|--------|---------| | `eleven_multilingual_v2` | Text → Speech | 1/50 chars | | `eleven_text_to_sound_v2` | Text → Sound FX | 1/6 sec | | `eleven_voice_dubbing` | Audio → Dubbed | 1/2 sec | ## Valid Ratios | Ratio | Format | |-------|--------| | `1280:720` | 16:9 landscape (standard) | | `720:1280` | 9:16 portrait (Reels/Stories) | | `1584:672` | 21:9 ultra-wide | | `1104:832` | 4:3 | | `832:1104` | 3:4 | | `960:960` | Square | ## Duration - **gen4.5:** 2–10 seconds - **gen4_turbo:** 5 or 10 seconds ## Task Polling All operations are async. The SDK's `.waitForTaskOutput()` handles polling automatically (10 min timeout). **Statuses:** `PENDING` → `THROTTLED` → `RUNNING` → `SUCCEEDED` / `FAILED` Manual poll: ```bash curl "https://api.dev.runwayml.com/v1/tasks/{task_id}" \ -H "Authorization: Bearer $RUNWAYML_API_SECRET" \ -H "X-Runway-Version: 2024-11-06" ``` ## Prompting Tips - Describe single scenes (5–10 sec clips) - Use clear physical descriptions, not abstract concepts - For camera movement: "slow dolly-in", "tracking shot", "push toward subject" - **Avoid negative phrasing** — "no blur" produces unpredictable results - Keep prompts grounded and physically plausible ## Official Docs - [Runway API Documentation](https://docs.dev.runwayml.com/) - [Model Guide](https://docs.dev.runwayml.com/guides/models/) - [Developer Portal](https://dev.runwayml.com/)