Swagger example body implementation

I want to create a swagger documentation for my project. So my controller like that:

@request("get", "/campaign")
@summary("Get all campaigns for advertiser")
@path({
    access_token: { type: "number", required: true, description: "access_token of user" },
    advertiser_id: { type: "number", required: true, description: "advertiser id of user" }
})
public static async getAllCampaigns(ctx: Context): Promise<void> {
    var status = 400
    var body = {}

But I want to add example request body as key&pair. I new to swagger And I cannot do this. How can I add example body as key value form with swagger?