New · Multilingual code-switching
AI that answers
AI that answers
the phone.
Build, test, and run voice agents on real phone lines.
10K+
GitHub stars across projects
1M+
Docker pulls
275
releases shipped
2018
building since
Built for real calls.
Ana R.
AgentHi Ana — calling to confirm Thursday at 3 PM.
Ana¿Podemos pasarlo al viernes en la mañana?
Toolcalendar.reschedule("fri 10:00")
Agent¡Listo! Viernes a las 10 AM. Nos vemos.
Confirms, reschedules, and books — in the caller's language.
- Outbound calls
- Custom tools
- Code-switching
Everything a phone call needs.
Phone numbers
SIP trunking
Call transfer
Voicemail detection
Barge-in
Multilingual
Knowledge base
Custom tools
MCP server
Call recording
Noise filtering
Events & webhooks
Any model.
Any carrier.
Swap providers with one line. No lock‑in.
Call
PSTN · SIP · WebRTC
Hear
Deepgram · Google
Think
OpenAI · Anthropic
Gemini · Groq · Ollama
Gemini · Groq · Ollama
Speak
ElevenLabs · Azure
Deepgram · Google
Deepgram · Google
Autopilot
Your agent is a YAML file.
Pick the voice, the model, and the prompt. Deploy with one command.
Learn more about Autopilotname: front-desktype: AUTOPILOTspeechToText: productRef: stt.deepgram config: { model: nova-3, languageCode: multi }textToSpeech: productRef: tts.deepgram config: { voice: aura-asteria-en }intelligence: productRef: llm.openai config: languageModel: { provider: openai, model: gpt-4o } conversationSettings: firstMessage: "Hi! How can I help?" systemPrompt: "You book appointments." # + tools, knowledge base, transfer…name: front-desktype: AUTOPILOTspeechToText: productRef: stt.deepgram config: model: nova-3 languageCode: multitextToSpeech: productRef: tts.deepgram config: { voice: aura-asteria-en }intelligence: productRef: llm.openai config: languageModel: provider: openai model: gpt-4o conversationSettings: firstMessage: "Hi! How can I help?" systemPrompt: "You book appointments." # + tools, knowledge base, transfer…
$
npx @fonoster/ctl applications:create -f agent.yaml
Done!