How to Develop a Multilingual Conversational Agent for Website and PBX

Learn how to build a multilingual AI voice agent that works seamlessly on both websites and PBX systems using VaxVoIP SIP SDK and WebPhone SDK. This intelligent solution integrates real-time voice processing with OpenAI’s Realtime API for dynamic, natural-sounding interactions.

Why Use VaxVoIP SDKs for AI Voice Agents

VaxVoIP provides both a SIP Server SDK and a WebPhone SDK, allowing developers to deploy smart conversational agents that respond in multiple languages. The SDK supports real-time access to VoIP PCM audio and is ideal for integration with OpenAI Whisper for speech recognition and GPT for voice interaction.

Visual C# .NET

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Visual Basic .NET

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Key Components

VaxVoIP SIP Server SDK for server-side SIP communication
VaxVoIP WebPhone SDK to connect browser visitors with AI agents
AI support through Whisper and GPT integration
Named pipe audio routing for real-time audio processing
Sample code available in both C# and VB.NET

Sample Code Availability

VaxVoIP provides ready-to-use sample projects in both C# and VB.NET. These samples show how to:

Access SIP call PCM audio
Use NamedPipeClientStream for audio routing
Integrate OpenAI’s WebSocket API
Send and receive speech-to-speech data in real time

Integration with Website and PBX

For Website Visitors

Using the WebPhone SDK, visitors can talk directly to the AI voice agent from their browser. The audio is routed to the SIP Server SDK, which then communicates with the AI backend.

For PBX or SIP Phones

The smart agent built with the VaxVoIP SIP Server SDK can connect with third-party SIP-based PBX systems, becoming a natural extension of your current VoIP infrastructure.

Integration Workflow

Capture live PCM audio from the SIP call or webphone
Send the audio to Whisper or another ASR engine
Pass the transcription to GPT or your preferred language model
Convert the response into speech using a TTS engine
Stream the audio reply back to the user in real time

Use Cases

Website customer service voice agents
PBX-based AI receptionists
AI-driven IVR systems with multilingual logic
Healthcare voice bots for patient interaction
Travel and booking agents with real-time language support

Benefits of This Integration

Real-time intelligent voice interaction
Natural multilingual conversations
Available 24/7 without human staff
Works across both browser and SIP networks
Reduces load on support teams
Fully customizable logic and responses

Conclusion

By combining VaxVoIP SIP Server SDK and WebPhone SDK with OpenAI’s real-time AI models, you can develop multilingual AI voice agents that work across any VoIP network and website. Whether you’re integrating into a new service or enhancing an existing SIP PBX system, this solution gives you flexibility, scalability, and intelligent automation.

Ready to build your AI-powered voice system? Get started today with the available C# and VB.NET sample projects from VaxVoIP.