Search messages by date | Mailchimp Transactional API Reference
Search recently sent messages and optionally narrow by date range, tags, senders, and API keys. If no date range is specified, results within the last 7 days are returned. This method may be called up to 20 times per minute. If you need the data more often, you can use /messages/info.json to get the information for a single message, or webhooks to push activity to your own application for querying.