Editor's Note: This is an installment of our new series called Things Every Alexa Skill Should Do, which highlights the important features and lessons that every skill builder can use to make their skills more engaging for customers. Follow the series to learn, get inspired, and build engaging Alexa skills.

When building a skill, you might find yourself making assumptions about what a customer might say. It is important to make sure that you’re anticipating something completely outside your expected set of responses, and handling it in a way that allows the customer to get back on the rails.

In the Dev Tips skill, for example, we encourage developers to ask the skill about the issue or topic that they want to know more about. This also means that there will be times that a customer says something we didn’t expect.

When testing how a skill handles unexpected utterances, we like to use the phrase “pizza pie.” We use this to see if the skill handles words the developer didn’t plan for, and see how the skill responds. In the case of Dev Tips, “pizza pie” will deliver a response similar to this one:

“I heard you say pizza pie. I’m sorry, I don’t know how to help you with that.”

The skill acknowledges that it heard the customer, and it even repeats the words captured in the slot value so that the user understands why it missed. This gives the customer an opportunity to try their question again, or ask a different one.

By handling these errors gracefully, the customer understands that what they requested wasn’t available, but they can continue to interact with the skill.

To learn more, check out the Alexa Voice Design Guide. Or enable the new Fallback Intent in the Alexa Skills Kit built-in library to respond gracefully to out-of-domain requests to your Alexa skill.

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