Vapi is the developer-first way to put a voice AI agent on a phone line. It handles the hard real-time plumbing — telephony, speech-to-text, LLM orchestration, text-to-speech, interruption handling — while you bring your own models and logic. Think of it as the infrastructure layer between your phone system and your AI stack.

The flexibility is the draw: swap LLMs, voices, and transcription providers per use case, script complex call flows, and integrate with your backend via webhooks and an API that's clearly built by people who've shipped real systems. Latency tuning and interruption handling — the things that make voice agents feel human or robotic — are notably well done.

Budget honestly: the advertised $0.05/minute is the platform fee only. Add LLM, voice, transcription, and telephony providers and real-world costs land around $0.30/minute, with enterprise deployments running thousands per month. And it's genuinely developer-first — if you want a no-code visual builder, this isn't it.

🐱 SAGE SAYS

The best voice-agent infrastructure for teams who can code, and the wrong choice for everyone else. Do the math at $0.30/minute against your call volume before you fall in love with the demo.

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