---
title: Creating with Aleph 2 (Runway)
description: Edit a video you already have with Aleph 2, Runway's video-to-video model: add or remove objects, relight a scene or change the angle.
---
Aleph 2 is Runway's in-context video-to-video editing model, available on invideo. Your agent calls it as `aleph2`. It is an editing layer after generation. Take a video you already made or uploaded, and change it with a text prompt. Add or remove objects, change the camera angle, relight the scene or change a character, without a new shoot or a new generation.

Aleph 2 replaces the earlier Gen-4 Aleph model on invideo.

## How to get started

In the invideo app, open Aleph 2 from the generative models on the homepage.

1. Select **Generative models**, then **See all**, then **Aleph 2**.
2. Upload the video you want to edit. You can add keyframe images at set times in the clip.
3. Enter your prompt. Describe what you want to change.
4. Confirm the credit cost and generate.
5. Preview the result, refine it with follow-up prompts, and download it.

The agent uses the same model through `generate` and reads the inputs with `get_model`.

Your agent runs a dry run first. For any call that costs 1 credit or more, it tells you the price and waits for your yes. A call under 1 credit runs without asking, and your agent tells you what it cost. Aleph 2 charges by the length of the source video.

## Spec information

`aleph2` takes a `video` and a `prompt`, both required. Optional `keyframes` are images, each pinned to a time in the source clip. The aspect ratios are 16:9, 9:16, 4:3, 1:1, 3:4 and 21:9. For the length of source video it takes, the agent reads `get_model`.

## Prompt best practices

Aleph 2 works best when you describe the edit precisely: what exists, what should change and what should stay the same.

*Example: Keep the product and table surface. Change the background to a dark moody kitchen at night. Add soft warm rim lighting from the right.*

| Tip | Why it helps |
| --- | --- |
| Describe what stays, as well as what changes | Being explicit about what stays avoids edits you did not want |
| Specify lighting direction and quality | The model relights scenes well when you name the light source and its quality |
| Use camera language for angle changes | "Change to a medium close-up" or "shift to bird's eye view" gives the model a precise target |
| Use keyframe images to pin a look | A keyframe image at a set time shows the model what that moment should look like |

Models retire. If a model is not found, your agent runs `find_models` with the job in words, uses the best match, and tells you. See [Models](/reference/models#when-a-model-retires).