Mailgun keeps track of every inbound and outbound message event and stores this data for at least 3 days.
WARNING: This API is deprecated in favor of our Logs API. 
Mailgun tracks every inbound and outbound message event and retains this data for at least 3 days. See Filter expression for details about filtering expressions
| begin | string The beginning of the search time range in epoch seconds  | ||||||
| end | string The end of the search time range in epoch seconds  | ||||||
| ascending | string Sort direction by time. Must be provided if the range end time is not specified. Can be either yes or no 
  | ||||||
| limit | integer  <= 300  The number of entries to return (300 max)  | ||||||
| event | string Filter by event type  | ||||||
| list | string Filter by mailing list email address that message was originally sent to  | ||||||
| attachment | string Filter by the name of an attached file  | ||||||
| from | string Filter by email address mentioned in the From MIME header  | ||||||
| message-id | string Filter by Mailgun message id returned by the messages API  | ||||||
| subject | string Filter by subject line  | ||||||
| to | string Filter by email address mentioned in the To MIME header  | ||||||
| size | string Filter by message size. Mostly intended to be used with range filtering expressions  | ||||||
| recipient | string Filter by email address of a recipient. While messages are addressable to one or more recipients, each event (with one exception) tracks one recipient. See stored events for use of recipients  | ||||||
| recipients | string Specific to stored events, this field tracks all of the potential message recipients.  | ||||||
| tags | string Filter by user defined tags  | ||||||
| severity | string Filter by event severity, if exists. Currently for failed events only. See Tracking Failures 
  | 
OK
Array of objects  | |
object  | 
{- "items": [
- {
- "event": "rejected",
 - "id": "OMTXD3-sSmKIQa1gSKkYVA",
 - "timestamp": 1529704976.104692,
 - "log-level": "warn",
 - "flags": {
- "is-test-mode": false
 
}, - "reject": {
- "reason": "Sandbox subdomains are for test purposes only. Please add your own domain or add the address to authorized recipients in Account Settings.",
 - "description": ""
 
}, - "message": {
- "headers": {
- "to": "joan@example.org",
 - "message-id": "20180622220256.1.B31A451A2E5422BB@sandbox55887fac92de874df5ae0023b75fd62f1d.mailgun.org",
 - "from": "john@sandbox55887fac92de874df5ae0023b75fd62f1d.mailgun.org",
 - "subject": "Test Subject"
 
}, - "attachments": [ ],
 - "size": 867
 
}, - "tags": [ ],
 - "user-variables": { }
 
} 
], - "paging": {
} 
}