Meet the Voice Sommelier
When people think about AI, they tend to focus on its intelligence. But the more you use AI agents, the more you realize there’s something else at play: expression. It’s not just what they know that’s important, but how they say it — and how the conversation makes you feel.
I was hired as Sierra’s first Agent Experience Designer to make the agents built on our platform sound and feel just right for the brands they represent. A few weeks into the job, I joked that the role should really be “Voice Sommelier” — because helping craft an agent’s voice is a lot like picking a good wine. Everyone has an opinion, tastes differ, and most people lack the words to describe exactly what they want. You need to listen, translate and offer just enough advice for them to make the right decision. The name stuck, and I’ve been known as Voice Sommelier ever since.
Design your voice
With voice, first impressions are especially important. It’s the difference between someone continuing the conversation, hanging up, or immediately asking to speak with a customer service representative. Basic performance, like speed and accuracy, matters, but tone earns you trust.
So I start the design process by understanding the brand. Not just a company’s values and tone-of-voice guidelines, but how they want people to feel. Then I look at their customers: their mindsets, goals, and emotional states. And from there, I guide clients through a simple but revealing exercise: celebrity touchstones. If any actor — living or dead — could be the voice of your brand, who would it be?
This isn’t just a feel-good exercise. It helps surface a brand’s emotional presence and vocal traits. Warm or witty? Elite or for everyone? Funny or serious? All of the above? Sometimes we find a great match with one of our high-performing house voices, like Jade, Tatyana, or Steven. In other cases, we will design a custom voice, source a new voice actor, or even use the voice of a real customer support rep.
The uncanny valley of voice
Our goal is not to build a human replica — it’s to create something that feels human in all the right ways. That’s a finer line than you might imagine. It requires you to:
- Focus on performance cues that help the agent feel grounded: breath, rhythm, stress, pitch, and (sparingly) human ticks like “um” or “hmm.”
- Lean into vocal textures that one might call defects — a touch of gravel, “vocal fry” (that low, creaky register), or a little breathiness. Used in moderation, they make the voice feel lived-in, and real.
- Tune different parts of the experience for different emotional cues: efficient for a refund, upbeat for a product recommendation, warm when things go well, empathetic when they don’t.
- Listen, hypothesize, iterate, and test — always remembering voice is just the top layer.
What your voice says
Designing the right voice is just the start. The agent also needs to say the right things, in the right way, at the right time.
Scripting and conservation design bring the experience together, making sure agents sound confident or apologize when appropriate, handle frustration gracefully, and lean into the right brand language. As a Voice Sommelier, I work closely with our customers and agent development team — the people who design the conversations an agent handles and integrate them with backend systems — to help the agent perform like a great actor interpreting a script.
The metrics that matter
We design voice agents for three important outcomes:
- Acceptance: Did the customer stick around after hearing the agent? Or immediately ask for a person? That first moment of trust is often won or lost on tone alone.
- Resolution: Did the agent resolve the issue? Clear communication, emotional intelligence, and confident delivery keep people engaged.
- Satisfaction: Did the customer feel helped and cared for? We’ve seen that when a voice feels intentional and aligned with the brand, customers rate the experience more favorably, even when the results are the same.
Experiences customers remember
As the saying goes, people don’t always remember exactly what you said or did, but they always remember how you made them feel.
Every day, I help amazing companies find just the right voice for their brand — one that reflects their values, serves their customers, and elegantly connects the two.
Want help creating a great agent for your business?
