Sim

Twilio Voice

Make and manage phone calls

Twilio Voice is a powerful cloud communications platform that enables businesses to make, receive, and manage phone calls programmatically through a simple API.

Twilio Voice provides a robust API for building sophisticated voice applications with global reach. With coverage in over 100 countries, carrier-grade reliability, and a 99.95% uptime SLA, Twilio has established itself as the industry leader in programmable voice communications.

Key features of Twilio Voice include:

  • Global Voice Network: Make and receive calls worldwide with local phone numbers in multiple countries
  • Programmable Call Control: Use TwiML to control call flow, record conversations, gather DTMF input, and implement IVR systems
  • Advanced Capabilities: Speech recognition, text-to-speech, call forwarding, conferencing, and answering machine detection
  • Real-time Analytics: Track call quality, duration, costs, and optimize your voice applications

In Sim, the Twilio Voice integration enables your agents to leverage these powerful voice capabilities as part of their workflows. This creates opportunities for sophisticated customer engagement scenarios like appointment reminders, verification calls, automated support lines, and interactive voice response systems. The integration bridges the gap between your AI workflows and voice communication channels, enabling your agents to deliver timely, relevant information directly through phone calls. By connecting Sim with Twilio Voice, you can create intelligent agents that engage customers through their preferred communication channel, enhancing the user experience while automating routine calling tasks.

Usage Instructions

Integrate Twilio Voice into the workflow. Make outbound calls and retrieve call recordings.

Tools

twilio_voice_make_call

Make an outbound phone call using Twilio Voice API.

Input

ParameterTypeRequiredDescription
tostringYesPhone number to call (E.164 format, e.g., +14155551234)
fromstringYesYour Twilio phone number to call from (E.164 format)
urlstringNoURL that returns TwiML instructions for the call
twimlstringNoTwiML instructions to execute (alternative to URL). Use square brackets instead of angle brackets, e.g., [Response][Say]Hello[/Say][/Response]
statusCallbackstringNoWebhook URL for call status updates
statusCallbackMethodstringNoHTTP method for status callback (GET or POST)
accountSidstringYesTwilio Account SID
authTokenstringYesTwilio Auth Token
recordbooleanNoWhether to record the call
recordingStatusCallbackstringNoWebhook URL for recording status updates
timeoutnumberNoTime to wait for answer before giving up (seconds, default: 60)
machineDetectionstringNoAnswering machine detection: Enable or DetectMessageEnd

Output

ParameterTypeDescription
successbooleanWhether the call was successfully initiated
callSidstringUnique identifier for the call
statusstringCall status (queued, ringing, in-progress, completed, etc.)
directionstringCall direction (outbound-api)
fromstringPhone number the call is from
tostringPhone number the call is to
durationnumberCall duration in seconds
pricestringCost of the call
priceUnitstringCurrency of the price
errorstringError message if call failed

twilio_voice_list_calls

Retrieve a list of calls made to and from an account.

Input

ParameterTypeRequiredDescription
accountSidstringYesTwilio Account SID
authTokenstringYesTwilio Auth Token
tostringNoFilter by calls to this phone number
fromstringNoFilter by calls from this phone number
statusstringNoFilter by call status (queued, ringing, in-progress, completed, etc.)
startTimeAfterstringNoFilter calls that started on or after this date (YYYY-MM-DD)
startTimeBeforestringNoFilter calls that started on or before this date (YYYY-MM-DD)
pageSizenumberNoNumber of records to return (max 1000, default 50)

Output

ParameterTypeDescription
successbooleanWhether the calls were successfully retrieved
callsarrayArray of call objects
totalnumberTotal number of calls returned
pagenumberCurrent page number
pageSizenumberNumber of calls per page
errorstringError message if retrieval failed

twilio_voice_get_recording

Retrieve call recording information and transcription (if enabled via TwiML).

Input

ParameterTypeRequiredDescription
recordingSidstringYesRecording SID to retrieve
accountSidstringYesTwilio Account SID
authTokenstringYesTwilio Auth Token

Output

ParameterTypeDescription
successbooleanWhether the recording was successfully retrieved
recordingSidstringUnique identifier for the recording
callSidstringCall SID this recording belongs to
durationnumberDuration of the recording in seconds
statusstringRecording status (completed, processing, etc.)
channelsnumberNumber of channels (1 for mono, 2 for dual)
sourcestringHow the recording was created
mediaUrlstringURL to download the recording media file
pricestringCost of the recording
priceUnitstringCurrency of the price
uristringRelative URI of the recording resource
transcriptionTextstringTranscribed text from the recording (if available)
transcriptionStatusstringTranscription status (completed, in-progress, failed)
transcriptionPricestringCost of the transcription
transcriptionPriceUnitstringCurrency of the transcription price
errorstringError message if retrieval failed

Notes

  • Category: tools
  • Type: twilio_voice
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