vapi
Vapi is the developer platform for voice agents: build, test, and operate AI phone assistants with sub-second latency.
Vapi is a developer platform for phone and voice agents: You combine a language model, speech recognition, and voice via API to create an assistant that answers calls or makes calls itself. The Y-Combinator startup has established itself as an infrastructure standard in the voice AI scene.
It can be used to build appointment scheduling for practices, lead qualification in sales, and order taking in restaurants. Its strength lies in its flexibility: any model, any voice, and any telephony connection can be combined, with latencies under one second.
Dialogflow is more established in classic contact centers, and ready-made solutions like What AI Services handle the entire setup for you. With Vapi, you build it yourself: little can be done without developers, and the costs from per-minute rates, language model, voice, and telephony quickly add up with volume.
Ideal for teams with developers who want to build and operate voice agents according to their own specifications. Anyone who just wants a ready-made phone AI is better off buying an industry solution or hiring an agency.
Functions
- Sub-second latency for natural-sounding conversations
- SOC 2, HIPAA, and PCI compliance
- Squads: multiple agents hand off conversations to each other
- Billing per conversation minute plus costs of selected providers
- German voices via providers like ElevenLabs
Core Functions
- Voice Agents for Inbound and Outbound Telephony via API
- Flexible choice of language model, speech synthesis, and speech recognition
- Phone Numbers, SIP Connectivity, and Web Calls
- Tool calls during the conversation, such as calendar or CRM
- Test Suites and Monitoring for Call Quality
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