TeXML Answering Machine Detection Support

TeXML is an XML-based data structure you can use to control calls with Telnyx and is the quickest way to get started with Programmable Voice using a simple .xml file, allowing you to specify call instructions in your file using commands called verbs and nouns.

Initiating a TeXML outbound call using REST endpoint with AMD enabled

There are 2 possible options for using Answering Machine Detection for outbound calls:

Synchronous mode: In this case, the TeXML instructions are not executed until the results of AMD process are provided in the status callback. The new instructions can be sent back as response to be processed by the TeXML engine.
Asynchronous mode: Here, the TeXML instructions are processed in parallel to the AMD process. The results of the AMD analysis are being provided in the AsyncAmdStatusCallback callback.

Synchronous mode request

The outbound TeXML call with AMD support enable in the synchronous mode can be requested in the following way:

Don’t forget to update YOUR_API_KEY here.

    curl --request POST \
      --url https://api.telnyx.com/v2/texml/Accounts/{account_sid}/Calls \
      --header 'Authorization: Bearer YOUR_API_KEY' \
      --header 'Content-Type: application/json' \
      --data '{
      "From": "+13127367421",
      "To": "your-sip-user@sip.telnyx.com",
      "Url": "https://your-server.example.com/texml/instructions",
      "FallbackUrl": "https://your-server.example.com/texml/fallback",
      "StatusCallback": "https://your-server.example.com/callback/status",
      "StatusCallbackMethod": "POST",
      "Method": "POST",
      "MachineDetection": "Enable",
      "DetectionMode": "Premium",
      "AsyncAmd": false
    }'

The results of the analysis will be sent as a value of the AnsweredBy parameter of the StatusCallback request.

`AnsweredBy` parameter values

The values returned depend on the MachineDetection mode used: When MachineDetection is Enable (detects as soon as the answering machine is identified):

Value	Description
`human`	A human answered the call
`machine_start`	An answering machine was detected (detection completes immediately)
`fax`	A fax machine was detected
`unknown`	Detection was inconclusive

When MachineDetection is DetectMessageEnd (waits for the answering machine greeting to finish):

Value	Description
`human`	A human answered the call
`machine_end_beep`	Answering machine greeting ended with a beep detected
`machine_end_silence`	Answering machine greeting ended with silence
`machine_end_other`	Answering machine greeting ended (other detection)
`fax`	A fax machine was detected
`unknown`	Detection was inconclusive

The MachineDetection parameter accepts the following values: Enable, Disable (default), and DetectMessageEnd. The DetectionMode parameter accepts Regular (default) or Premium.

Asynchronous mode request

Similarly, the asynchronous AMD processing can be requested for outgoing TeXML calls:

    curl --request POST \
      --url https://api.telnyx.com/v2/texml/Accounts/{account_sid}/Calls \
      --header 'Authorization: Bearer YOUR_API_KEY' \
      --header 'Content-Type: application/json' \
      --data '{
      "From": "+13127367421",
      "To": "your-sip-user@sip.telnyx.com",
      "Url": "https://your-server.example.com/texml/instructions",
      "FallbackUrl": "https://your-server.example.com/texml/fallback",
      "Method": "POST",
      "StatusCallback": "https://your-server.example.com/callback/status",
      "StatusCallbackMethod": "POST",
      "MachineDetection": "Enable",
      "DetectionMode": "Premium",
      "AsyncAmd": true,
      "AsyncAmdStatusCallback": "https://your-server.example.com/callback/amd-status",
      "AsyncAmdStatusCallbackMethod": "POST"
    }'

The results of the AMD analysis will be sent as callback requests to the address provided as AsyncAmdStatusCallback parameter. Note that this can be used for basic and premium AMD.

`AsyncAmdStatusCallback` parameters

The callback to your AsyncAmdStatusCallback URL includes the following parameters:

Parameter	Description
`AnsweredBy`	The result of AMD analysis. See the AnsweredBy parameter values table above for the full list of mode-dependent values (`human`, `machine_start`, `machine_end_beep`, `machine_end_silence`, `machine_end_other`, `fax`, `unknown`)
`CallSid`	The unique identifier for the call
`CallSidLegacy`	Legacy call identifier (same as `CallSid`)
`AccountSid`	Your Telnyx account SID
`ConnectionId`	The unique identifier of the connection used for the call
`MachineDetectionDuration`	The duration of the machine detection in milliseconds

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TeXML Answering Machine Detection Support

Initiating a TeXML outbound call using REST endpoint with AMD enabled

Synchronous mode request

`AnsweredBy` parameter values

Asynchronous mode request

`AsyncAmdStatusCallback` parameters

​Initiating a TeXML outbound call using REST endpoint with AMD enabled

​Synchronous mode request

​AnsweredBy parameter values

​Asynchronous mode request

​AsyncAmdStatusCallback parameters

Initiating a TeXML outbound call using REST endpoint with AMD enabled

Synchronous mode request

`AnsweredBy` parameter values

Asynchronous mode request

`AsyncAmdStatusCallback` parameters