Vapi

Vapi is a developer-focused platform for building, testing, and deploying advanced voice AI agents. It provides APIs and SDKs that allow you to create natural, real-time conversational experiences over phone calls, web, or mobile applications. Vapi handles low-latency audio streaming, speech-to-text, text-to-speech, and orchestration with large language models, so developers can focus on conversation logic and integration rather than telephony or audio infrastructure.

Key capabilities include configurable call flows, custom prompts, and support for multiple LLM providers. Developers can integrate external APIs and back-end systems, enabling agents to access databases, CRMs, booking systems, or internal tools during live conversations. Vapi also offers tools for testing conversations, monitoring call quality, analyzing transcripts, and iterating on agent behavior based on real usage data.