Building an AI Coach to Help Tame My Monkey Mind

Eugene Yan has a familiar problem: a restless mind, imposter syndrome, and the endless chase for the next dopamine hit. His usual fixes—meditation, morning pages, gratitude journaling—all shared the same blind spot. They're introspective. None of them talk back.

So he turned to ChatGPT as an ad hoc therapist, and found it genuinely useful for a year. Then a tweet from Swyx nudged him toward voice, a modality he'd previously written off thanks to years of shouting at Siri and getting nowhere. This time it stuck. Yan built a voice-based AI coach he now talks to on his morning walks, using it to rehearse hard conversations, sort through half-formed ideas, and reflect his own emotions back at him before he even reaches the office.

The setup is Claude 3 Sonnet paired with Vapi, a voice API platform that handles the messy parts of conversation—knowing when to pause for an interruption, knowing when to shut up while someone thinks. Yan says that combination is what finally made voice feel natural instead of stilted. He named the assistant Tara, gave her a system prompt asking for casual speech, filler words, and radical candor capped at 200 words a response, and hooked her up to a real phone number anyone can dial.

He's also published the entire recipe: create an assistant on Vapi, write a first message and system prompt, rent a virtual number for two dollars a month, assign it, publish, done. Ten minutes, he claims, and no coding beyond copy-pasting a prompt. It's a small, almost domestic use of AI—no benchmarks, no funding round—just someone testing whether a language model can substitute for a sounding board that's awake at 6 a.m.

What's notable isn't the tech stack, which is fairly plain, but the framing. Yan isn't pitching a startup. He's describing a coping mechanism, one he's openly inviting strangers to dial into, which says something about how comfortable talking to a machine about your anxieties has quietly become.