HappyHorse-1.0 API documentation

Integrate HappyHorse-1.0 with your VezAPI key. The operations below share the same authentication and account balance.

Base URL: https://api.vezapi.com
Send Authorization: Bearer YOUR_VEZAPI_KEY. Use a unique Idempotency-Key for each submission; reuse it only when checking the same request.

happyhorse-image-to-video

POST/api/v1/jobs/createTask

Model IDs: happyhorse/image-to-video

Parameter	Type	Description & constraints
`model` required	`string`	The model name to use for generation. Required field. - Must be `happyhorse/image-to-video` for this endpoint Values: `"happyhorse/image-to-video"` Default: `"happyhorse/image-to-video"`
`callBackUrl` optional	`string`	The URL to receive generation task completion updates. Optional but recommended for production use. - System will POST task status and results to this URL when generation completes - Callback includes generated content URLs and task information - Your callback endpoint should accept POST requests with JSON payload containing results - Alternatively, use the Get Task Details endpoint to poll task status - To ensure callback security, see [Webhook Verification Guide](/common-api/webhook-verification) for signature verification implementation
`input` required	`object`	Input parameters for the generation task
`input.prompt` optional	`string`	Text prompt describing the video to generate (any language). Up to 5,000 characters. `maxLength: 5000`
`input.image_urls` required	`array`	First-frame image URL list. Exactly one image is required. Image constraints: Format: JPEG, JPG, PNG, WEBP. Resolution: Width and height must be at least 300 pixels. Aspect ratio: 1:2.5 to 2.5:1. File size: Up to 10 MB. `maxItems: 1`
`input.resolution` optional	`string`	Output video resolution: 720p or 1080p (default). The output keeps the aspect ratio of the input image; 720p / 1080p set the resolution tier. Values: `"720p", "1080p"` Default: `"1080p"`
`input.duration` optional	`integer`	Output duration in seconds. Must be between 3 and 15. Defaults to 5. Default: `5` `minimum: 3` `maximum: 15`
`input.seed` optional	`integer`	Random seed for reproducibility. Default: `0` `minimum: 0` `maximum: 2147483647`

Request example

curl -X POST 'https://api.vezapi.com/api/v1/jobs/createTask' \
  -H 'Authorization: Bearer YOUR_VEZAPI_KEY' \
  -H 'Idempotency-Key: your-unique-request-id' \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "happyhorse/image-to-video",
  "input": {
    "prompt": "A cat running on the grass",
    "image_urls": [
      "Your prompt"
    ],
    "resolution": "1080p",
    "duration": 5
  }
}'

Responses and errors

HTTP 200

Request successful

Parameter	Type	Description & constraints
`code` optional	`integer`	Status code of the request. The HTTP status is 200 even when the request fails, so always check this field: 200 means success; any other value means the request failed and msg describes the reason. Common values: 401 invalid or missing API key; 402 insufficient credits; 429 rate limit exceeded; 422 or 500 the request could not be processed (read msg and check your parameters before retrying). Values: `200, 401, 402, 404, 422, 429, 433, 455, 500, 501, 505`
`msg` optional	`string`	Response message, error description upon failure
`data` required	`object`
`data.taskId` required	`string`	The task ID can be used with the "Get Task Details" endpoint to query the task status.

happyhorse/reference-to-video

POST/api/v1/jobs/createTask

Model IDs: happyhorse/reference-to-video

Parameter	Type	Description & constraints
`model` required	`string`	The model name to use for generation. Required field. - Must be `happyhorse/reference-to-video` for this endpoint Values: `"happyhorse/reference-to-video"` Default: `"happyhorse/reference-to-video"`
`callBackUrl` optional	`string`	The URL to receive generation task completion updates. Optional but recommended for production use. - System will POST task status and results to this URL when generation completes - Callback includes generated content URLs and task information - Your callback endpoint should accept POST requests with JSON payload containing results - Alternatively, use the Get Task Details endpoint to poll task status - To ensure callback security, see [Webhook Verification Guide](/common-api/webhook-verification) for signature verification implementation
`input` required	`object`	Input parameters for the generation task
`input.prompt` required	`string`	Text prompt describing the video to generate (any language). Up to 5,000 characters. `maxLength: 5000`
`input.reference_image` required	`array`	Reference image URL list. Provide 1–9 images. The order defines which image is character1, character2, etc. Image limits: Format: JPEG, JPG, PNG, and WEBP. Resolution: shortest side at least 400 px. 720P or higher recommended. Avoid small, blurry, or heavily compressed images, as they degrade output quality. File size: 10 MB maximum. `minItems: 1` `maxItems: 9`
`input.resolution` optional	`string`	Output video resolution: 720p or 1080p (default). Values: `"720p", "1080p"` Default: `"1080p"`
`input.aspect_ratio` optional	`string`	Output aspect ratio. Valid values: 16:9 (default), 9:16, 1:1, 4:3, 3:4. Values: `"16:9", "9:16", "1:1", "4:3", "3:4"` Default: `"16:9"`
`input.duration` optional	`integer`	Output duration in seconds (integer). Must be between 3 and 15. Defaults to 5. Default: `5` `minimum: 3` `maximum: 15`
`input.seed` optional	`integer`	Random seed for reproducibility. Default: `0` `minimum: 0` `maximum: 2147483647`

Request example

curl -X POST 'https://api.vezapi.com/api/v1/jobs/createTask' \
  -H 'Authorization: Bearer YOUR_VEZAPI_KEY' \
  -H 'Idempotency-Key: your-unique-request-id' \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "happyhorse/reference-to-video",
  "input": {
    "prompt": "A woman in a red qipao character1. The shot opens with a side medium view outlining the tailored fit of the qipao and S-curve silhouette, then cuts to a low-angle shot capturing her gracefully unfolding a folding fan character2, with tassel earrings character3 swaying lightly as she turns her head. Finally, the camera pushes into a facial close-up, freezing on her fingertips lightly touching the fan ribs and the subtle, reserved charm in her expressive gaze. Through multiple angles, it comprehensively showcases an aura of Eastern elegance.",
    "reference_image": [
      "Your prompt"
    ],
    "resolution": "1080p",
    "aspect_ratio": "16:9",
    "duration": 5
  }
}'

Responses and errors

HTTP 200

Request successful

Parameter	Type	Description & constraints
`code` optional	`integer`	Status code of the request. The HTTP status is 200 even when the request fails, so always check this field: 200 means success; any other value means the request failed and msg describes the reason. Common values: 401 invalid or missing API key; 402 insufficient credits; 429 rate limit exceeded; 422 or 500 the request could not be processed (read msg and check your parameters before retrying). Values: `200, 401, 402, 404, 422, 429, 433, 455, 500, 501, 505`
`msg` optional	`string`	Response message, error description upon failure
`data` required	`object`
`data.taskId` required	`string`	The task ID can be used with the "Get Task Details" endpoint to query the task status.

happyhorse-text-to-video

POST/api/v1/jobs/createTask

Model IDs: happyhorse/text-to-video

Parameter	Type	Description & constraints
`model` required	`string`	The model name to use for generation. Required field. - Must be `happyhorse/text-to-video` for this endpoint Values: `"happyhorse/text-to-video"` Default: `"happyhorse/text-to-video"`
`callBackUrl` optional	`string`	The URL to receive generation task completion updates. Optional but recommended for production use. - System will POST task status and results to this URL when generation completes - Callback includes generated content URLs and task information - Your callback endpoint should accept POST requests with JSON payload containing results - Alternatively, use the Get Task Details endpoint to poll task status - To ensure callback security, see [Webhook Verification Guide](/common-api/webhook-verification) for signature verification implementation
`input` required	`object`	Input parameters for the generation task
`input.prompt` required	`string`	Text prompt describing the video to generate (any language). Up to 5,000 characters. `maxLength: 5000`
`input.resolution` optional	`string`	Output video resolution: 720p or 1080p (default). Values: `"720p", "1080p"` Default: `"1080p"`
`input.aspect_ratio` optional	`string`	Output aspect ratio. Valid values: 16:9 (default), 9:16, 1:1, 4:3, 3:4. Values: `"16:9", "9:16", "1:1", "4:3", "3:4"` Default: `"16:9"`
`input.duration` optional	`integer`	Output duration in seconds (integer). Must be between 3 and 15. Defaults to 5. Default: `5` `minimum: 3` `maximum: 15`
`input.seed` optional	`integer`	Random seed for reproducibility. Default: `0` `minimum: 0` `maximum: 2147483647`

Request example

curl -X POST 'https://api.vezapi.com/api/v1/jobs/createTask' \
  -H 'Authorization: Bearer YOUR_VEZAPI_KEY' \
  -H 'Idempotency-Key: your-unique-request-id' \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "happyhorse/text-to-video",
  "input": {
    "prompt": "A miniature city built from cardboard and bottle caps comes to life at night. A cardboard train slowly passes through, with small lights dotting the scene and illuminating the way ahead.",
    "resolution": "1080p",
    "aspect_ratio": "16:9",
    "duration": 5
  }
}'

Responses and errors

HTTP 200

Request successful

Parameter	Type	Description & constraints
`code` optional	`integer`	Status code of the request. The HTTP status is 200 even when the request fails, so always check this field: 200 means success; any other value means the request failed and msg describes the reason. Common values: 401 invalid or missing API key; 402 insufficient credits; 429 rate limit exceeded; 422 or 500 the request could not be processed (read msg and check your parameters before retrying). Values: `200, 401, 402, 404, 422, 429, 433, 455, 500, 501, 505`
`msg` optional	`string`	Response message, error description upon failure
`data` required	`object`
`data.taskId` required	`string`	The task ID can be used with the "Get Task Details" endpoint to query the task status.

happyhorse/video-edit

POST/api/v1/jobs/createTask

Model IDs: happyhorse/video-edit

Parameter	Type	Description & constraints
`model` required	`string`	The model name to use for generation. Required field. - Must be `happyhorse/video-edit` for this endpoint Values: `"happyhorse/video-edit"` Default: `"happyhorse/video-edit"`
`callBackUrl` optional	`string`	The URL to receive generation task completion updates. Optional but recommended for production use. - System will POST task status and results to this URL when generation completes - Callback includes generated content URLs and task information - Your callback endpoint should accept POST requests with JSON payload containing results - Alternatively, use the Get Task Details endpoint to poll task status - To ensure callback security, see [Webhook Verification Guide](/common-api/webhook-verification) for signature verification implementation
`input` required	`object`	Input parameters for the generation task
`input.prompt` required	`string`	Required edit instruction describing the intended change (e.g., style transfer / local replacement). Up to 5,000 characters. `maxLength: 5000`
`input.video_url` required	`string`	URL of the input video (one video). Video requirements: Format: MP4, MOV (H.264 encoding recommended). Duration: 3–60 seconds. Resolution: the longer side must not exceed 2,160 px; the shorter side must be at least 320 px. Aspect ratio: 1:2.5–2.5:1. File size: up to 100 MB. Frame rate: greater than 8 fps.
`input.reference_image` optional	`array`	Optional reference image URL list (0–5). Image requirements: Format: JPEG, JPG, PNG, WEBP. Resolution: both width and height must be at least 300 px. Aspect ratio: 1:2.5–2.5:1. File size: up to 10 MB. `minItems: 0` `maxItems: 5`
`input.resolution` optional	`string`	Output video resolution: 720p or 1080p (default). Values: `"720p", "1080p"` Default: `"1080p"`
`input.audio_setting` optional	`string`	Audio handling: auto lets the model handle audio; origin keeps the input video's original audio where possible. Values: `"auto", "origin"` Default: `"auto"`
`input.seed` optional	`integer`	Random seed for reproducibility. Default: `0` `minimum: 0` `maximum: 2147483647`

Request example

curl -X POST 'https://api.vezapi.com/api/v1/jobs/createTask' \
  -H 'Authorization: Bearer YOUR_VEZAPI_KEY' \
  -H 'Idempotency-Key: your-unique-request-id' \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "happyhorse/video-edit",
  "input": {
    "prompt": "Make the horse-headed humanoid character in the video wear the striped sweater from the image",
    "video_url": "Your prompt",
    "resolution": "1080p"
  }
}'

Responses and errors

HTTP 200

Request successful

Parameter	Type	Description & constraints
`code` optional	`integer`	Status code of the request. The HTTP status is 200 even when the request fails, so always check this field: 200 means success; any other value means the request failed and msg describes the reason. Common values: 401 invalid or missing API key; 402 insufficient credits; 429 rate limit exceeded; 422 or 500 the request could not be processed (read msg and check your parameters before retrying). Values: `200, 401, 402, 404, 422, 429, 433, 455, 500, 501, 505`
`msg` optional	`string`	Response message, error description upon failure
`data` required	`object`
`data.taskId` required	`string`	The task ID can be used with the "Get Task Details" endpoint to query the task status.

Task status and callbacks

For asynchronous tasks, keep the returned taskId. Query GET /api/v1/jobs/recordInfo?taskId=... or provide callBackUrl when creating the task. Only the account that created a task can access it or derive new resources from it.

A timeout can mean the submission was accepted. Inspect the existing request in your dashboard; do not create another task automatically. Callback delivery is retried and may arrive more than once. Deduplicate with X-VezAPI-Event-Id.

Files, logs and billing

Generated media normally follows a 14-day provider lifetime; uploaded files expire after 24 hours. Save the files you need before expiration. VezAPI streams registered files without keeping a permanent media library. Request logs are retained for two calendar months.

Credits are reserved before submission. Final deductions match actual discounted consumption one for one. Unknown usage pauses new paid requests. If available funds cannot cover final usage while protecting other reservations, settlement stays pending until funded; model usage cannot make the wallet negative. Time-based inputs require server-side metadata reads; a failed read prevents submission.