***

title: Features and Capabilities
subtitle: Voice AI Orchestration on a Communications Platform
-------------------------------------------------------------

# Voximplant Platform Capabilities

Voximplant Platform is an established cloud communications platform for building programmable voice, video, and messaging applications using serverless call control, SDKs, and APIs.

<Note>
  Use this page as a capability map: scan the summary cards first, then expand only the detailed sections you care
  about.
</Note>

## Capabilities at a glance

<div>
  <CardGroup cols={3}>
    <Card title="Voice AI orchestration" icon="fa-duotone fa-waveform-lines" href="#voice-ai-orchestration">
      Connect real-time AI agents, speech systems, and telephony channels with code-driven orchestration.
    </Card>

    <Card title="Voice telephony" icon="fa-duotone fa-phone-volume" href="#voice-telephony">
      Run inbound/outbound PSTN, SIP, WebRTC, and WhatsApp voice flows with fine-grained call control.
    </Card>

    <Card title="Tools and DX" icon="fa-duotone fa-code" href="#tools-and-developer-experience">
      Use cloud IDE/debugging, multi-platform SDKs, and Management API automation.
    </Card>

    <Card title="Messaging" icon="fa-duotone fa-message" href="#messaging">
      Deliver SMS, in-app messaging, push notifications, and webhook-driven backend integrations.
    </Card>

    <Card title="Video telephony" icon="fa-duotone fa-video" href="#video-telephony">
      Build WebRTC video experiences with recording, screen sharing, and voice/video interoperability.
    </Card>

    <Card title="Media streaming + reliability" icon="fa-duotone fa-signal-stream" href="#realtime-media-streaming">
      Stream media over WebSockets and deploy globally on serverless infrastructure.
    </Card>
  </CardGroup>
</div>

## Voice AI vendors at a glance

### Direct agent and real-time connectors

<CardGroup cols={3}>
  <Card title="OpenAI Realtime" href="/voice-ai-connectors/openai/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/7800930955052cd54de5d4f4261ac4f76193011c10aa2a29b54ef5566cedd0dd/docs/assets/connectors/openai.svg" alt="OpenAI logo" />
    </span>

    Realtime and agent-style voice integrations.
  </Card>

  <Card title="Google Gemini Live" href="/voice-ai-connectors/gemini/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/404eba6940a54e63d40edcce2d2e7cb2b3dbfec765e7a1d523662b6f4e0d6747/docs/assets/connectors/gemini.svg" alt="Gemini logo" />
    </span>

    Live speech interactions with Gemini APIs.
  </Card>

  <Card title="Ultravox Realtime" href="/voice-ai-connectors/ultravox/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/77c44e07e74ef847190f30db5dd0235f9f545f530454c7e9102608a1e181c848/docs/assets/connectors/ultravox.svg" alt="Ultravox logo" />
    </span>

    WebSocket-based speech-native connector.
  </Card>

  <Card title="Deepgram Voice Agent" href="/voice-ai-connectors/deepgram/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/391f7d32e87f97489a3f409fc80a38bc8ef592617070e735055bfaa2c6e6f711/docs/assets/connectors/deepgram.svg" alt="Deepgram logo" />
    </span>

    Native voice-agent connector and examples.
  </Card>

  <Card title="ElevenLabs ElevenAgents" href="/voice-ai-connectors/elevenlabs/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/24e2fe318bc1ed54a29ceb867e4ecead952355cda4241b07402d1ff6510dc133/docs/assets/connectors/elevenlabs.svg" alt="ElevenLabs logo" />
    </span>

    Conversational AI agent integrations.
  </Card>

  <Card title="Cartesia Line Agents" href="/voice-ai-connectors/cartesia/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/b1c1db2b7dd505edc9e5b049837f77d220d2ad09c536579ef644cd905ba78b21/docs/assets/connectors/cartesia.png" alt="Cartesia logo" />
    </span>

    Line Agents runtime with VoxEngine orchestration.
  </Card>

  <Card title="xAI Grok Voice Agent" href="/voice-ai-connectors/grok/overview">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/07099f0e2eea46fe8cef6a2422dee63e1aa98c3cab07f3edf9a0b333314f758b/docs/assets/connectors/grok-x.svg" alt="xAI logo" />
    </span>

    Grok voice-agent flow and feature support.
  </Card>
</CardGroup>

### Speech and realtime TTS options

<CardGroup cols={3}>
  <Card title="Cartesia Realtime TTS" href="/voice-ai-connectors/openai/half-cascade-cartesia">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/b1c1db2b7dd505edc9e5b049837f77d220d2ad09c536579ef644cd905ba78b21/docs/assets/connectors/cartesia.png" alt="Cartesia logo" />
    </span>

    Realtime TTS pattern for half-cascade voice pipelines.

    API refs: [Cartesia module](https://voximplant.com/docs/references/voxengine/cartesia).
  </Card>

  <Card title="Inworld Realtime TTS" href="/voice-ai-connectors/openai/half-cascade-inworld">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/df8d1ce8f3d81610cf29ae13bc477bf7b709d0212f948cb60f9ca9b670e13b7e/docs/assets/connectors/inworld.png" alt="Inworld logo" />
    </span>

    Realtime TTS option for half-cascade voice flows.
  </Card>

  <Card title="ElevenLabs Streaming TTS" href="/voice-ai-connectors/openai/half-cascade-elevenlabs">
    <span>
      <img src="https://files.buildwithfern.com/voximplant.docs.buildwithfern.com/24e2fe318bc1ed54a29ceb867e4ecead952355cda4241b07402d1ff6510dc133/docs/assets/connectors/elevenlabs.svg" alt="ElevenLabs logo" />
    </span>

    Streaming/realtime TTS option for voice AI pipelines.

    API refs: [ElevenLabs module](https://voximplant.com/docs/references/voxengine/elevenlabs).
  </Card>
</CardGroup>

<div>
  <h2 id="detailed-capabilities">
    Detailed capabilities
  </h2>

  <div>
    <button type="button" data-capabilities-accordion-action="expand" aria-controls="capabilities-accordion-root">
      <span aria-hidden="true">▾</span> Expand all
    </button>

    <button type="button" data-capabilities-accordion-action="collapse" aria-controls="capabilities-accordion-root">
      <span aria-hidden="true">▴</span> Collapse all
    </button>
  </div>
</div>

<div id="capabilities-accordion-root">
  <AccordionGroup>
    ### Voice AI Orchestration

    <Accordion title="Voice AI Orchestration" defaultOpen={true}>
      Voximplant AI is a serverless runtime for **Voice AI pipelines** that connects real-time agent/LLM systems
      and speech engines to **PSTN / SIP / WebRTC / mobile / WhatsApp calling**, with code-driven orchestration
      and provider flexibility. See [Voximplant AI](https://voximplant.ai/) and the docs [Voice AI connectors
      section](/voice-ai-connectors/voice-ai-connectors-overview).

      **Supported vendors (direct agent / real-time LLM connectors)**

      Native/direct connectivity is positioned for:

      * **OpenAI** (Realtime / agent-style integrations) - [Docs:
        OpenAI](/voice-ai-connectors/openai/overview)
      * **Google Gemini (Live)** - [Docs:
        Google](/voice-ai-connectors/gemini/overview)
      * **Deepgram Voice Agent** - [Docs:
        Deepgram](/voice-ai-connectors/deepgram/overview)
      * **ElevenLabs Agents / Conversational AI** - [Docs:
        ElevenLabs](/voice-ai-connectors/elevenlabs/overview)
      * **Ultravox (WebSocket API)** - [Docs:
        Ultravox](/voice-ai-connectors/ultravox/overview)
      * **Cartesia Line Agents** - [Docs: Cartesia Line
        Agents](/voice-ai-connectors/cartesia/overview)
      * **xAI (Grok Voice Agent)** - [Docs:
        xAI](/voice-ai-connectors/grok/overview)

      Voximplant AI also explicitly supports connecting to **another WebSocket interface** (for other real-time AI
      systems) in addition to the vendors above.

      **Supported vendors (speech engines: STT / TTS)**

      Voximplant's platform speech layer (STT/TTS) includes built-in providers such as:

      * **Speech-to-Text (STT)**: Google Speech Cloud, Microsoft Azure STT, Amazon Transcribe, Yandex Speech Cloud
      * **Text-to-Speech (TTS)**: Google Speech Cloud, Amazon Polly, Yandex Speech Cloud, Microsoft Azure TTS,
        Tinkoff VoiceKit

      For realtime / streaming TTS used in Voice AI scenarios, Voximplant also provides native VoxEngine modules
      and guides for:

      * **Cartesia Realtime TTS** - [Guide: Realtime
        TTS](/voice-ai-connectors/openai/half-cascade-cartesia)
        and [API refs](https://voximplant.com/docs/references/voxengine/cartesia)
      * **Inworld Realtime TTS** - [Guide: Realtime
        TTS](/voice-ai-connectors/openai/half-cascade-inworld)
      * **ElevenLabs Streaming / realtime TTS** - [Guide: ElevenLabs
        TTS](/voice-ai-connectors/openai/half-cascade-elevenlabs)
        and [API refs](https://voximplant.com/docs/references/voxengine/elevenlabs)

      **Pipeline options (architectures you can run)**

      * **Speech-to-speech**: real-time audio in and real-time audio out (agent API handles full duplex loop)
      * **Speech -> LLM -> TTS**: stream audio directly into a speech LLM and use a different TTS for output
      * **STT -> LLM -> TTS**: stream audio to STT, pass text to an LLM/toolchain, synthesize response audio
      * **Hybrid**: combine a real-time agent API for turn-taking with separate best-of-breed STT/TTS components
        (mix and match)

      **Orchestration primitives (what you control)**

      * **Mix and match providers**: swap STT/TTS/LLM vendors without changing your telephony integration
      * **Parallel model execution**: run multiple speech/LLM components in parallel when useful (for example,
        intent extraction + generation)
      * **Failover paths**: fall back to alternate speech/LLM providers when a step errors or times out
      * **Wideband audio**: higher fidelity audio path for improved user experience and model comprehension
      * **Deep SIP support**: SIP trunking + registration interop so agents can operate inside PBX/SBC/carrier
        environments
      * **Channel portability**: reuse the same AI pipeline across PSTN numbers, SIP, WebRTC, mobile SDKs, and
        WhatsApp calling

      **Real-time media integration (streaming)**

      * **WebSocket-based media streaming** for connecting calls to real-time AI systems and custom pipelines
        (audio + metadata/control messages on the same channel)
      * **Media gateway abstraction**: avoid building/operating custom streaming gateways when using native
        connectors/modules
    </Accordion>

    ### Voice telephony

    <Accordion title="Voice telephony">
      **Connectivity and endpoints**

      * **PSTN calling** (inbound/outbound) via phone numbers and programmable call handling
      * **Phone numbers API**: automated procurement in **60+ countries** (availability varies by country)
      * **SIP calling and trunking**: connect carriers / PBXs / SBCs using SIP interop (including
        registration-based scenarios)
      * **WebRTC calling** via web/mobile SDKs (VoIP calling in apps and browsers)
      * **WhatsApp calling**: inbound/outbound voice calls via WhatsApp Business API integration

      **Serverless call control (VoxEngine)**

      * **JavaScript call logic (no XML)** for real-time call routing and application workflows
      * **Per-call-leg signaling/media control** - granular control over each leg independently

      **Conferencing and bridging**

      * **Single conferencing API** for voice/video; **mix PSTN, SIP, WebRTC, and native mobile endpoints**
      * **Conferences up to 50 participants**

      **Recording, transcription, and speech processing**

      * **Call recording** via `call.record()` in scenarios (supports stereo and additional options)
      * **Call transcription** via `record(transcribe=true)` and retrieval via `GetCallHistory` (transcription
        delivered asynchronously)
      * **Speaker/channel labeling** in transcripts (for example, "Left"/"Right" labeling pattern described in
        docs)

      **Speech-to-Text (ASR) modes and features**

      * **Phrase-hint mode** (best for constrained dialogs / IVRs) and **Freeform mode** (open transcription)
      * **Multiple ASR engines** (for example, Google, Amazon, Microsoft, Yandex, T-bank) with selectable profiles
      * **Intermediate results** support (provider-dependent) for faster partial recognition
      * **Google Speech v1p1beta1 feature passthrough** (for example, word time offsets, punctuation, diarization
        config)

      **Answering machine / voicemail / beep detection**

      * **AMD module** for voicemail/answering machine detection in scenarios
      * **Beep detection** with specified frequency lists and timeouts (scenario-level control)
      * **AMD event/callback model** available in VoxEngine references

      **Automated outbound calling (call lists + dialing logic)**

      * **Call Lists**: upload a **CSV call list** and process it with VoxEngine scenarios (campaign-style
        calling)
      * **Management API CallLists**: programmatic call-list upload/append with delimiter support
      * **Predictive Dialing System (PDS)**: uses agent/load statistics and call-list progression to place calls
        and connect answered calls to agents
      * **Predictive and progressive dialing modes** with tunable parameters (for example, allowed failed call
        percentage)
    </Accordion>

    ### Video telephony

    <Accordion title="Video telephony">
      **WebRTC video API (server-based + P2P)**

      * **Video API** to build server-based and P2P video experiences
      * SDKs abstract core WebRTC complexities:
      * **STUN/TURN/ICE**
      * **Bandwidth optimization**
      * **Video quality control**

      **Real-time collaboration features**

      * **Screen sharing** (share screen or window)
      * **Recording** for calls/conferences; storage in Voximplant Cloud or S3-compatible storage
      * **Video streaming** support (platform capability referenced in docs/features)

      **Voice/video interoperability**

      * Bridge **PSTN/SIP audio into video rooms** as part of a unified conferencing model
    </Accordion>

    ### Messaging

    <Accordion title="Messaging">
      **SMS**

      * **Send SMS via Management API** and **receive inbound SMS via HTTP callbacks** (for SMS-capable numbers)

      **Instant Messaging (in-app chat)**

      * **Direct messaging** between application users
      * **Chat rooms up to 1000 participants**
      * **Chatbots** for automated interactions

      **Push notifications (mobile)**

      * Push notifications to wake devices for **incoming calls** and **message notifications**
      * Android push implementation is based on **Firebase Cloud Messaging (FCM)**

      **Webhooks / event delivery to your backend**

      * **HTTP Callbacks** for event-driven notifications without polling the Management API
    </Accordion>

    ### Tools and Developer Experience

    <Accordion title="Tools and Developer Experience">
      **Cloud IDE and debugging**

      * **Cloud IDE + debugger** in the control panel:
      * **Code verification**
      * **Autocompletion**
      * **Diff highlighting**
      * Built-in troubleshooting workflow

      **SDKs and client libraries**

      * SDKs: **iOS, Android, Web, React Native, Flutter, Unity**
      * API clients: **curl, Node.js, Python, PHP, Go, .NET, Java**

      **Management API (HTTP)**

      * Control accounts/services programmatically (examples from docs include managing phone numbers, messaging,
        billing, logs, records, and user access)
    </Accordion>

    ### Real-time Media Streaming (WebSockets / Media Streams)

    <Accordion title="Real-time Media Streaming (WebSockets / Media Streams)">
      * **Media Streams**: integrate **live audio streams** into calls via WebSockets for real-time
        transcription/analysis and AI integrations
      * WebSocket programming model in VoxEngine:
      * Create connections via `VoxEngine.createWebSocket(...)`
      * Stream audio using `WebSocket.sendMediaTo(...)`
      * Recommended audio chunk duration: **\~20ms**
    </Accordion>

    ### Network, Reliability, and Deployment

    <Accordion title="Network, Reliability, and Deployment">
      * **Serverless runtime** (no infrastructure to manage for call logic)
      * **Global footprint**: datacenters in **14** distinct countries (as stated on the platform page)
      * **Status page** for live and historical uptime of subcomponents
    </Accordion>
  </AccordionGroup>
</div>