8cbbd788_ooks___Mandrill_Knowledge_Base__Event_Type
[Description] recipient opened a message; will only occur when open tracking is enabled [Event Type] 
Opened
S e n t
B o u n c e d
O p e n e d
M a r k e d A s S p a m
R e j e c t e d
D e l a y e d
S o f t - B o u n c e d
C l i c k e d
R e c i p i e n t U n s u b s c r i b e s
Introduction to Webhooks – Mandrill Knowledge Base
Event Type