> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crun.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Runway Gen4 Aleph
> Runway Aleph is an in-context video model that performs comprehensive video editing and transformation tasks on input videos. The model handles object manipulation, scene generation, environmental changes, and visual transformations through text prompts or reference images.
## Query Task Status
After submitting a task, use the unified query endpoint to check progress and retrieve results:
Learn how to query task status and retrieve generation results
For production use, we recommend using the `callback_url` parameter to receive automatic notifications when generation completes, rather than polling the status endpoint.
## Related Resources
Explore all available models
Check credits and account usage
## OpenAPI
````yaml models/runway/gen-4-aleph.json post /api/v1/client/job/CreateTask
openapi: 3.0.0
info:
title: Crun Runway Gen4 Aleph Video API
description: crun.ai Runway Gen4 Aleph API Documentation
version: 1.0.0
contact:
name: Technical Support
email: support@crun.ai
servers:
- url: https://api.crun.ai
description: API Server
security:
- ApiKeyAuth: []
paths:
/api/v1/client/job/CreateTask:
post:
summary: gen4 aleph video generation
operationId: runway/gen-4-aleph
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- model
- input
properties:
model:
type: string
enum:
- runway/gen-4-aleph
description: |-
The model name to use for generation. Required field.
- Must be `runway/gen-4-aleph` for this endpoint
callback_url:
type: string
format: uri
description: >-
Optional. Callback URL for receiving task completion
notifications.
- System will POST task status and results to this URL when
generation completes
- Callback payloads structure is consistent with the `data`
object returned by the task status query
- Your callback endpoint should accept POST requests with
JSON payload containing results
- It returns an HTTP 200 status code upon successful receipt
example: https://your-domain.com/api/callback
input:
type: object
description: >-
Input parameters for the Runway Gen-4 Aleph model, designed
for video-to-video transformations and style transfers.
properties:
prompt:
type: string
description: >-
Text prompt to guide the video transformation or style.
**Prompting recommendations**:
- An action verb that describes what you want to do
(such as add, remove, change, replace, re-light, and
re-style)
- A description of your desired transformation
minLength: 1
maxLength: 1500
example: >-
Transform this city street video into a steampunk
aesthetic with brass pipes and steam vents.
video_urls:
type: array
description: >-
Input video to generate from. Videos must be less than
16MB.
**Note**:
Current limitation: outputs are capped at 5 seconds; if
your input video exceeds 5 seconds, only the first 5
seconds will be processed.
items:
type: string
format: uri
minItems: 1
maxItems: 1
example:
- https://example.com/original-footage.mp4
aspect_ratio:
type: string
description: Aspect ratio of the output video.
enum:
- '1:1'
- '3:4'
- '4:3'
- '9:16'
- '16:9'
- '21:9'
- auto
default: auto
example: '16:9'
img_urls:
type: array
description: >-
Optional reference image to influence the style or
content of the output.
items:
type: string
format: uri
maxItems: 1
example:
- https://example.com/style-reference.jpg
seed:
type: integer
description: Random seed. Set for reproducible generation
minimum: 0
maximum: 4294967295
example: 20240501
required:
- prompt
- video_urls
example:
model: runway-gen4-turbo
input:
prompt: >-
A slow camera pan across an ancient library with floating
books and dust motes dancing in sunbeams.
duration: 10
aspect_ratio: '4:3'
resolution: 720p
responses:
'200':
description: Request successful
content:
application/json:
schema:
allOf:
- $ref: '#/components/schemas/ApiResponse'
- type: object
properties:
data:
type: object
properties:
task_id:
type: string
description: >-
Task ID, can be used with Get Task Details
endpoint to query task status
example: task_12345678
example:
code: 200
message: success
data:
task_id: task_12345678
'422':
description: Validation Error
content:
application/json:
schema:
allOf:
- $ref: '#/components/schemas/ApiResponse'
- type: object
properties:
errors:
type: array
description: Detailed validation error messages
items:
type: string
example:
- specific error field message
example:
code: 422
message: Missing Params or Type Error
errors:
- specific error field message
'500':
$ref: '#/components/responses/Error'
components:
schemas:
ApiResponse:
type: object
properties:
code:
type: integer
enum:
- 200
- 401
- 402
- 404
- 422
- 429
- 455
- 500
- 501
- 505
description: >-
Response status code
- **200**: Success - Request has been processed successfully
- **401**: Unauthorized - Authentication credentials are missing or
invalid
- **402**: Insufficient Credits - Account does not have enough
credits to perform the operation
- **404**: Not Found - The requested resource or endpoint does not
exist
- **422**: Validation Error - The request parameters failed
validation checks
- **429**: Rate Limited - Request limit has been exceeded for this
resource
- **455**: Service Unavailable - System is currently undergoing
maintenance
- **500**: Server Error - An unexpected error occurred while
processing the request
- **501**: Generation Failed - Content generation task failed
- **505**: Feature Disabled - The requested feature is currently
disabled
message:
type: string
description: Response message, error description when failed
example: success
responses:
Error:
description: Server Error
securitySchemes:
ApiKeyAuth:
type: apiKey
in: header
name: x-api-key
description: >-
All APIs require authentication via API Key.
Get API Key:
1. Visit [API Key Management Page](https://crun.ai/user-api-key) to get
your API Key
Usage:
Add to request header:
x-api-key: YOUR_API_KEY
Note:
- Keep your API Key secure and do not share it with others
- If you suspect your API Key has been compromised, reset it immediately
in the management page
````