This used to work. I have Zapier create activities that trigger workflows thru automations. Those workflows USED TO BE linked to the contact automatically. Since the API upgrade this is no longer the case.

Support says "This is because Automations are triggered by manual actions taken by the user. Items would require an additional 'touch' if created by an outside entity electronically such as Zapier"

Old change logs show this was an issue with the old API and was resolved, this should be simple to fix with the new one. Please address as it kind of defeats the purpose of an automation.