Samira is running a multi-ad campaign for a transport company and she needs each vehicle model's ID passed from the creative to the clickthrough URL. How can she achieve this?

Adding a custom field at the ad level allows Samira to define a unique ID for each vehicle model. This custom field can then be used as a token within the creative's clickthrough URL. When the ad is served, the ad server dynamically replaces the token with the specific vehicle model ID associated with that ad, ensuring the correct ID is passed to the landing page. Special instructions to placements are for operational notes, not for dynamic data passing. Using an API to pass additional data is generally for more complex, programmatic integrations, not for a straightforward creative-to-URL data transfer like this. Stating it's not possible is incorrect, as ad servers are designed for this type of dynamic content delivery.