If you complete a task in Todoist in a specific folder and want to notify to someone who doesn't use todoist just email them automatically. eg. If you have booked a show in and completed this task in project show. email to your friends who are part of it.

This Trigger fires every time a task is marked as completed in Todoist.

This Action will send an email to up to twenty recipients from your Gmail account.

IF a task is completed in specific project mail to required people.