Skip to main content
Voice Mail Detection automatically detects when outbound calls are routed to voicemail, so the agent does not speak to a recording or wait for a person who is not there. Voice Mail Detection lets you:
  • Detect voicemail systems automatically.
  • Control how your agent responds.
  • End calls cleanly after voicemail handling.

Setup

Import VoiceMailDetector and put it on the Pipeline, alongside the providers. Give it an llm to classify with, and the runtime runs the detector when the session is started with zeroruntime.invoke().
To set up outbound calling and routing rules, check out Handling Calls.

How it works

The detector buffers the opening speech on an outbound call for duration seconds, then asks the llm to classify the transcript as a human or a voicemail greeting (a one-word yes/no). Detection is handled by the runtime, which calls the agent’s on_voicemail back when it fires. Pass callback= on the detector instead to route it to a plain function.

Parameters

What’s Next

DTMF Events

Capture caller key presses.

Call Transfer

Move a live call to another number.