Is there documentation that Marketo provides that explains each action / trigger / filter? Some are intuitive, but ones are less so like "alert was sent" or "program status".
This is definitely something that you can find by searching in the bar above... But here is a link to Josh Hill's guide with some of them: You searched for triggers and filters - Marketing Rockstar Guides
There is an updated Operators on docs.marketo.com too.
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