UserContentBuilder

DSL for building the multimodal content of a single UserMessage.

Appends ContentParts in call order; at least one part is required. Images are only read by both models the API serves.

Example:

client.chat {
    user {
        text("Compare these two shots")
        image("https://example.com/before.jpg")
        imageFile("file-api-abc123")
    }
}