Using the V2 API, I know that the "action_by" query string parameter determines whether a Welcome Email is sent when a contact is added (ACTION_BY_OWNER vs. ACTION_BY_VISITOR).
However, I do not see, in the API documentation, any apparent mechanism for controlling autoresponder (as distinct from Welcome) emails when a (possibly existing) contact is added to a new list. Current behavior is that when I subscribe an existing contact to a new list using the API, the autoresponder associated with subscribing to that list is triggered. I am looking for the ability in the API PUT (or POST, if new contact) request to suppress the autoresponder email when contact is added to a new list.
Does this capability exist in the V2 API?
Thank you for reaching out to Constant Contact API Developer Support.
Autoresponder email campaigns are triggered by when a contact is newly added to the list associated with the Autoresponder. This happens outside of the API, so there is no way to prevent them from being sent an Autoresponder campaign if they are added to the appropriate list(s).
Can you share a bit more about your use case? I may have a possible workaround option for you.
Please let us know if you have any other questions!
Tier II API Support Engineer