Datadog
Adding a Contact
Datadog Events are triggered using the Application Keys integrations, available from the Integrations ➡️ APIs section of your Datadog portal. All you'll need is an API Key to enable Datadog Events.
In Datadog
In the Datadog portal, navigate to the Integrations ➡️ APIs section.
Make sure you have at least one API Key generated. If not, select Create API key to generate a new key:

In the Portal
You can add a new Datadog Contact from the Manage ➡️ Contacts section of the Portal:

Select Datadog from the Contact Type drop-down, enter the API Key in the API Key field, select your perferred API Endpoint region, select a Frequency, and select one or more Contact Groups to associate with this new contact.
After clicking Add Contact, you'll receive a confirmation message with a confirmation link that you'll need to click on to confirm your contact.

If you don't receive the confirmation message for some reason, you can also click the Resend Auth option to resend the confirmation message. Once a contact is confirmed, it will be ready to use.