Detect answering machines on outbound calls with synchronous or asynchronous detection modes.
Introduction
Important: Not a Separate Endpoint. Machine detection is NOT a separate API endpoint. It is configured as parameters when making a call using POST https://api.vobiz.ai/api/v1/Account/{auth_id}/Call/. This page documents the machine detection parameters and callback format.
Machine detection is only supported on outbound calls initiated via the Make Call API. Set the machine_detection parameter to enable this feature. Synchronous Machine Detection
When you set machine_detection=true or machine_detection=hangup when making a call, Vobiz analyzes the audio after the call is answered to determine if a machine answered.
| Field | Type | Required | Description |
|---|
machine_detection | string | No | Set to “true” to continue the call or “hangup” to automatically hang up when a machine is detected. |
machine_detection_time | integer | No | Time in milliseconds to analyze audio. Default: 5000. Range: 2000–10000. |
machine_detection_maximum_speech_length | integer | No | Maximum speech duration in milliseconds. Default: 5000. Range: 1000–6000. |
machine_detection_initial_silence | integer | No | Maximum silence after answer in milliseconds. Default: 4500. Range: 2000–10000. |
machine_detection_maximum_words | integer | No | Maximum number of sentences. Default: 3. Range: 2–10. |
machine_detection_initial_greeting | integer | No | Maximum greeting length in milliseconds. Default: 1500. Range: 1000–5000. |
Asynchronous Machine Detection
To act on a detected answering machine, set the machine_detection_url parameter when making an outbound call. Vobiz detects the answering machine in the background and invokes machine_detection_url with the results.
| Field | Type | Required | Description |
|---|
machine_detection_url | string | No | Callback URL invoked when machine detection completes. Vobiz sends detection results to this URL. |
machine_detection_method | string | No | HTTP method used to invoke machine_detection_url. Default: POST. |
Benefit: Asynchronous detection allows your application to handle the call immediately while detection happens in the background, providing better user experience.
Parameters Sent to machine_detection_url
When machine detection completes, Vobiz sends these parameters to your machine_detection_url:
| Field | Type | Description |
|---|
From | string | The caller ID number used to initiate the call. |
Machine | boolean | true if a machine was detected. |
To | string | Destination of the call. |
RequestUUID | string | Unique identifier for the call request. |
ALegRequestUUID | string | Identifier for the first leg of the call (multi-leg calls). |
CallUUID | string | Unique identifier for the call. |
IfMachine | string | "continue" or "hangup", reflecting the machine_detection value set when initiating the call. |
Direction | string | Direction of the call. Always "outbound" (machine detection is only supported on outbound calls). |
ALegUUID | string | Unique identifier for the A leg of the call. |
Event | string | Event that triggered this notification. Always "MachineDetection". |
CallStatus | string | Status of the call. Always "in-progress". |
Example Callback Response
JSON Sent to machine_detection_url
{
"From": "+12025550000",
"Machine": true,
"To": "+12025551111",
"RequestUUID": "9834029e-58b6-11e1-b8b7-a5bd0e4e126f",
"ALegRequestUUID": "9834029e-58b6-11e1-b8b7-a5bd0e4e126f",
"CallUUID": "97ceeb52-58b6-11e1-86da-77300b68f8bb",
"IfMachine": "continue",
"Direction": "outbound",
"ALegUUID": "97ceeb52-58b6-11e1-86da-77300b68f8bb",
"Event": "MachineDetection",
"CallStatus": "in-progress"
}
