> ## 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 Gateway Nodes

Voice Gateway Nodes help you build a voice AI Agent using [Voice Gateway configuration](/voice-gateway/overview).

<CardGroup cols={3}>
  <Card title="Call Recording" href="/ai/agents/develop/node-reference/voice/voice-gateway/call-recording">
    The Call Recording Node starts or stops a conversation recording.
  </Card>

  <Card title="DTMF" href="/ai/agents/develop/node-reference/voice/voice-gateway/dtmf">
    The DTMF Node plays DTMF digits to the caller.
  </Card>

  <Card title="Hang Up" href="/ai/agents/develop/node-reference/voice/voice-gateway/hangup">
    The Hang Up Node instructs Voice Gateway to end the call.
  </Card>

  <Card title="Mute Speech Input" href="/ai/agents/develop/node-reference/voice/voice-gateway/mute-speech-input">
    The Mute Speech Input Node controls when speech and DTMF user inputs are collected in your Flow.
  </Card>

  <Card title="Play" href="/ai/agents/develop/node-reference/voice/voice-gateway/play">
    The Play Node[^1] lets you stream a sound file into the call, also in a loop. The Node supports encoded MP3 and WAV files.
  </Card>

  <Card title="Send Metadata" href="/ai/agents/develop/node-reference/voice/voice-gateway/send-metadata">
    The Send Metadata Node sends metadata via SIP INFO messages to the connected SIP trunk.
  </Card>

  <Card title="Set Session Config" href="/ai/agents/develop/node-reference/voice/voice-gateway/set-session-config">
    The Set Session Config Node configures the Voice Gateway session. This configuration applies for the rest of the session unless overwritten, either directly or by activity parameters.
  </Card>

  <Card title="Transfer" href="/ai/agents/develop/node-reference/voice/voice-gateway/transfer">
    The Transfer Node lets you transfer an ongoing call to a Tel or SIP target.
  </Card>
</CardGroup>

[^1]: This Node can be configured with [Parameter Details](/ai/agents/develop/node-reference/voice/voice-gateway/parameter-details).