enroll_automation adds contacts to a published automation. The assistant does not enroll a draft, and it does not enroll anyone until you ask.
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What the assistant calls
1
Read published automations
list_automations returns published automations that can be enrolled. list_workflows shows draft and published status if you need to tell those apart.2
Enroll
enroll_automation takes up to 100 contacts. The assistant calls it only after you ask, and only when the automation is published.