This article tells how to send your API documentation to your MailBox
Step 1. Login to your MailboxLayer Account
Go to https://mailboxlayer.com/ and do login or Create MailboxLayer Account if you don’t have

Step 2. After Login You will get API Key - Copy the API Key

Step 3. Input Token
Go to Setup click more Menu then choose Developer Configuration

Step 4. Validation and Input Token
Go to tab MailBox layer then set 'Yes' and input the API Token you get
