Happy Horse API

Happy Horse is available through the cheapmodel Video API with cheapmodel token authentication, normalized task IDs, and USD billing. The model returns audio by default for video generation.

Base URL
https://cheapmodel.ai/video/v1
https://cheapmodel.ai/v1/video

Models

Model	Use case	Endpoint
`happyhorse-1.0-t2v`	Text-to-video	`POST /video/generations`
`happyhorse-1.0-i2v`	Image-to-video using one first frame image	`POST /video/generations`
`happyhorse-1.0-r2v`	Reference-to-video with 1-9 reference images	`POST /video/generations`
`happyhorse-1.0-video-edit`	Video editing with an input video and optional reference images	`POST /video/edits`

Create a Text-to-Video Task

curl https://cheapmodel.ai/video/v1/video/generations \
  -H "Authorization: Bearer YOUR_CHEAPMODEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse-1.0-t2v",
    "prompt": "A cinematic street scene at night, handheld camera, natural motion",
    "resolution": "720P",
    "ratio": "16:9",
    "duration": 5,
    "watermark": false
  }'

Create an Image-to-Video Task

curl https://cheapmodel.ai/video/v1/video/generations \
  -H "Authorization: Bearer YOUR_CHEAPMODEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse-1.0-i2v",
    "input": {
      "prompt": "Make the subject walk forward naturally",
      "media": [
        {"type": "first_frame", "url": "https://example.com/first-frame.png"}
      ]
    },
    "parameters": {
      "resolution": "720P",
      "duration": 5,
      "watermark": false
    }
  }'

Create a Reference-to-Video Task

curl https://cheapmodel.ai/video/v1/video/generations \
  -H "Authorization: Bearer YOUR_CHEAPMODEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse-1.0-r2v",
    "input": {
      "prompt": "Use image 1 as the character, image 2 as the scene, image 3 as the prop.",
      "media": [
        {"type": "reference_image", "url": "https://example.com/character.png"},
        {"type": "reference_image", "url": "https://example.com/scene.png"},
        {"type": "reference_image", "url": "https://example.com/prop.png"}
      ]
    },
    "parameters": {
      "resolution": "720P",
      "ratio": "9:16",
      "duration": 5,
      "watermark": false
    }
  }'

Create a Video Edit Task

curl https://cheapmodel.ai/video/v1/video/edits \
  -H "Authorization: Bearer YOUR_CHEAPMODEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse-1.0-video-edit",
    "input": {
      "prompt": "Keep the original motion, change the scene into a sunny park.",
      "media": [
        {"type": "video", "url": "https://example.com/input.mp4"},
        {"type": "reference_image", "url": "https://example.com/style.png"}
      ]
    },
    "parameters": {
      "resolution": "720P",
      "audio_setting": "origin",
      "watermark": false
    }
  }'

Query a Task

curl https://cheapmodel.ai/video/v1/video/generations/TASK_ID \
  -H "Authorization: Bearer YOUR_CHEAPMODEL_KEY"

Parameters

Field	Supported values
`resolution`	`720P`, `1080P`. Defaults to upstream behavior.
`ratio`	`16:9`, `9:16`, `1:1`, `4:3`, `3:4` where supported.
`duration`	Integer seconds from 3 to 15 for generation models.
`seed`	Integer from 0 to 2147483647.
`watermark`	Boolean. Upstream default is true.
`audio_setting`	Video edit only: `auto` or `origin`.

Billing

Happy Horse billing is calculated after the task completes, using the model usage response. Current USD reference prices are $0.13/sec for 720P output and $0.24/sec for 1080P output. cheapmodel rounds the final USD amount to two decimal places and records it in the user's account history.