Voice Tools

Voicemail Drop

Automatically leave pre-recorded voicemail messages when your outbound call reaches an answering machine.

Voicemail Drop

The Voicemail Drop tool detects when an outbound call reaches voicemail and automatically leaves a pre-recorded or AI-generated message. Instead of the AI agent awkwardly talking to an answering machine, it leaves a clean, professional voicemail.

How It Works

  1. Your agent makes an outbound call.
  2. The call goes to voicemail (answering machine detected).
  3. The agent waits for the beep.
  4. The agent plays your configured voicemail message.
  5. The call ends automatically.

Configuration

Via the Dashboard

  1. Open your agent and scroll to Voice Settings.
  2. Enable Voicemail Drop.
  3. Configure:
SettingDescription
Message typePre-recorded audio file or AI-generated text
Message textThe voicemail script (for AI-generated)
Audio fileUpload an MP3/WAV file (for pre-recorded)
Retry on voicemailRetry the call later instead of leaving a message
Max retriesNumber of retry attempts before leaving a voicemail

Via the API

curl -X PATCH https://api.thinnest.ai/agents/agent_abc123 \
  -H "Authorization: Bearer $THINNESTAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "voice_tools": {
      "voicemail_drop": {
        "enabled": true,
        "message_type": "text",
        "message": "Hi, this is a call from Acme Corp regarding your recent inquiry. Please call us back at 1-800-555-0123 at your earliest convenience. Thank you!",
        "retry_on_voicemail": true,
        "max_retries": 2
      }
    }
  }'

Voicemail Detection

thinnestAI uses audio analysis to detect voicemail greetings. Detection accuracy is high but not 100%. You can configure the sensitivity:

SensitivityBehavior
lowOnly triggers on clear voicemail signals (fewer false positives)
medium (default)Balanced detection
highAggressive detection (may occasionally trigger on slow human pickups)

Best Practices

  • Keep voicemail messages under 30 seconds.
  • Include a callback number and reason for the call.
  • For campaigns, personalize the message with the contact's name.
  • Use the retry option for important calls before falling back to voicemail.

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