The builder
Thetemplate helper returns an immutable builder — chain .body(), .header(), .button(), and .carousel() to add components:
Parameter helpers
Every variable in your template matches one of these factories. The type name is thetype field on the parameter.
Header, body, buttons
button(index, ...) — quick-reply button, payload parameter.
urlButton(index, ...) — URL button, text parameter appended to the approved base URL.
Indexes correspond to the button positions defined when the template was approved.
Carousel templates
Carousels are body templates with per-card components:components list uses the same TemplateComponentInput shape the body builder produces — you can construct them with template(...) sub-builders or inline them.