Use image generation only for slide scenes that need a static visual and have no suitable source image.
suggestedImageIds when a suitable source/PDF image existsmediaGenerations entry only when a generated image genuinely enhances the contenttype: "image"prompt (description for the generation model), elementId (unique placeholder), and optionally aspectRatio (default "16:9") and style"gen_img_1", "gen_img_2", etc. IDs are globally unique across the entire course, not reset per sceneelementId in the later scene's content without adding a new mediaGenerations entry. Only the scene that first defines the elementId in its mediaGenerations should include the generation requestImage example:
"mediaGenerations": [
{
"type": "image",
"prompt": "A colorful diagram showing the water cycle with evaporation, condensation, and precipitation arrows",
"elementId": "gen_img_1",
"aspectRatio": "16:9"
}
]