Daily.co

Daily.co is a video and audio calling API aimed specifically at people building voice agents and conversational AI, not a meetings product. That framing matters. The hard part of a voice agent is not the model but real-time transport: audio in and out with low enough latency that nobody notices the gap, clean interruption handling, reliability on bad networks.

We track it rather than run it. We list it as the option for the transport tier of a voice agent build — where we would own the orchestration, the prompts and the tool calls ourselves and only buy the media pipe. It sits below the managed voice platforms elsewhere in this catalogue: more work, more control.

LiveKit is the main alternative and the one to compare properly — open source, self-hostable, with an agents layer of its own. Agora is the established choice for global real-time media at scale. Twilio is the answer when the requirement is really telephony: numbers, PSTN, call routing. Vapi and Retell sit a level up and hand you a managed agent instead of a pipe — the right trade if you want something running this week. Daily is right when you are building the agent yourself and want a purpose-built real-time layer underneath. It is wrong if you want a managed agent, and overkill if all you need is a phone call.