Voice Ui Design

Conversational Design Principles

1. Be brief. Voice responses longer than 15 seconds lose users.
2. Be relevant. Answer the question first, then offer options.
3. Be transparent. Tell users what you can and can't do.
4. Provide escape hatches. "You can say 'stop' at any time."
5. Confirm destructive actions. "Delete all reminders. Are you sure?"

Prompt Design

• Open prompts: "What would you like to do?" (broad, intimidating)
• Closed prompts: "Would you like to order the same as last time?" (specific, easy)
• Guided prompts: "You can say 'reorder,' 'browse menu,' or 'check order.'" (helps discovery)

Error Handling

• "I didn't catch that. Could you say it again?"
• After 2 failures: "Let me show you some options instead."
• After 3 failures: transfer to screen-based UI or human.