Add many creatives to a campaign in one request. Each item is created or fails on its own, and the answer is 207 with a result per item, matched by your client_ref.

Needs the campaigns:write scope, like every campaign write.

An Idempotency-Key header (a UUID) is required. Repeating a request with the same key returns the first answer without creating anything again. The same key with a different body answers 409. The body may be up to 10 MiB.

Items take the same fields as Create campaign creative, plus client_ref.