At the moment, your agents can initiate a call within Zendesk Chat, Messaging and Sunshine.

All options above allow agents to send both clickable URLs and call cards, however some of them might require Agent Workspace enabled.

If you send emails or SMS within Zendesk, you can of course include a SnapCall URL within the content of your message, so that your customer can join the call with your agent.

Depending on the tool you're using or the way you'd like to initiate a Snapcall within Zendesk, you might need different plans and subscriptions enabled, you can find more on that at the following link.