Design and generate thumbnails
generate_thumbnailsCreates thumbnail concepts from a title and context, then renders 1280x720 JPGs under 2 MB for YouTube uploads or A/B tests; optionally builds on a reference video frame.
Instructions
Designs thumbnail concepts for a title (text overlay + image prompt) with the text model, then renders them with the image model (OpenAI gpt-image, Azure OpenAI image deployments, Gemini image). Optionally builds on a video frame. Saves 1280x720 JPGs under 2 MB, ready for set_thumbnail or create_ab_test. Without an image model it returns the concepts only.
Tool call template
Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {
"title": "<title>"
},
"name": "generate_thumbnails"
}
}Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| count | No | ||
| style | No | e.g. "bold, high contrast, face on the left, dark background" | |
| title | Yes | ||
| context | No | What the video is about, the subject, the audience. | |
| reference_image | No | Path to a frame or photo to build on. |