> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cognigy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Voice

> Learn how to build voice agents in Cognigy: add voice tools, set up telephony, or use speech to speech.

*Voice* lets your agents talk to callers over the phone. You create an agent, set how it speaks and listens, and connect it to a phone number. Cognigy handles speech recognition, conversation, and speech synthesis during the call.

## Get started

**1. Check your setup**

Review what voice supports and check that your project is ready:

> [card] [Explore technical specifications](https://docs.cognigy.com/ai/agents/develop/voice/technical-specifications.md)
>
> Review the supported protocols, audio codecs, trunk routing, speech providers, call recording, and call quality tools.

> [card] [Configure speech and telephony](https://docs.cognigy.com/ai/administer/access/speech-and-telephony.md)
>
> Ask your administrator to configure the speech providers and telephony connections for your project.

**2. Choose how to build your voice agent**

Decide whether to use agents or flows. Select a tab to see the voice features for each.

> [tab] Agents
>
> The following features are available only for agents:
>
> > [card] [Voice studio](https://docs.cognigy.com/ai/agents/develop/voice-configuration.md#voice-studio)
> >
> > Set the speech providers, voice, greeting, turn taking, and listening options for an agent. Not available when speech to speech is on.
>
> > [card] [Voice tools](https://docs.cognigy.com/ai/agents/develop/voice-configuration.md#voice-tools)
> >
> > Let an agent hang up, transfer, or play audio during a call.
>
> > [card] [Speech to speech](https://docs.cognigy.com/ai/agents/develop/voice/speech-to-speech.md)
> >
> > Experimental. Run a real-time voice model for natural conversation, backed by your existing agent. Replaces the text-to-speech and speech-to-text settings.

> [tab] Flows
>
> The following features are available only for flows:
>
> > [card] [Voice nodes](https://docs.cognigy.com/ai/agents/develop/node-reference/voice/voice-gateway/overview)
> >
> > Build call logic with voice nodes, for example, to set session parameters, collect keypad input, play audio, or transfer the call.

## Try additional features

The following features work with agents and flows:

> [card] [Outbound calls](https://docs.cognigy.com/ai/agents/develop/voice/outbound-calls)
>
> Start calls from Cognigy to a phone number or another system, and track call statuses through webhooks and call events.

> [card] [TTS streaming](https://docs.cognigy.com/ai/agents/develop/voice/tts-streaming.md)
>
> Play synthesized speech as it's generated to reduce response latency.

> [card] [Click To Call](https://docs.cognigy.com/click-to-call/overview.md)
>
> Embed a voice widget in your website so that customers can speak directly with agents.

> [card] [Voice endpoint](https://docs.cognigy.com/ai/agents/deploy/endpoint-reference/voice-gateway.md)
>
> Connect an agent to your contact center or other phone numbers with the Voice endpoint.

## More information

* [Agents](https://docs.cognigy.com/ai/agents/overview)
* [Flows](https://docs.cognigy.com/ai/agents/develop/projects-and-flows/overview)
* [Tools](https://docs.cognigy.com/ai/agents/develop/tools.md)