### Throw on Variable Not Found (Beta)

#### Ensuring Accuracy and Reliability in Automated Messaging

Throw on Variable Not Found is a cutting-edge feature Courier introduced, now in public beta and actively under development. This powerful tool enhances the integrity of your automated messaging system by preventing the delivery of messages containing unfulfilled variables. Developers are encouraged to provide feedback through Discord or their account team on Slack to help refine this feature further.

**Feature Overview**

Throw on Variable Not Found can be toggled in the notification template settings page under the advanced section. Once activated, Courier will halt any channel from sending a message if required variables within that template are not fulfilled. For instance, if an email template includes a placeholder such as Hello {profile.first_name}, but the first_name variable is missing in both the Courier profile and the Send API call, Courier will generate an error during the rendering process of that email template. This feature is operational when rendering a Preview Test event and is visible within Message Log render events. Check out the [documentation](https://www.courier.com/docs/platform/content/variables/variable-not-found/) for more information on using conditionals, multiple channels, and observability.

This feature is primarily designed for developers and teams responsible for implementing notification systems using Courier. It is essential for those who want to maintain high message integrity and accuracy standards, ensuring no faulty or incomplete messages are delivered to end users.

**Why you should use this feature**

Developers should integrate Throw on Variable Not Found to enhance the overall quality of their notification system. This feature allows for more predictable and manageable message rendering, reducing the potential for errors that could negatively impact user experience. By using this tool, developers can ensure that they meet their intended message design and content goals, leading to more professional and effective communication.

**Benefits for Developers**

- **Error Prevention:** Ensures that no messages with unfulfilled variables are sent out, reducing the risk of sending incomplete or erroneous messages.

- **Increased Reliability:** Boosts the reliability and trustworthiness of the messaging system by guaranteeing that all dynamic content is properly rendered.

- **Easy Debugging:** Provides clear feedback through logs, making identifying and debugging issues related to missing variables easier.

**Benefits for End Users**

- **Consistent Experience:** End users receive fully rendered messages, ensuring a seamless and professional communication experience.

- **Enhanced Engagement:** By receiving complete and accurate messages, users are more likely to engage positively with the content.

In conclusion, Throw on Variable Not Found significantly elevates the quality and reliability of automated messaging. By preventing the sending of messages with unfulfilled variables, this robust feature ensures a consistent, accurate, and user-friendly communication experience. Developers and end-users alike will benefit from the enhanced integrity and performance this feature brings to the messaging system.