Twilio Voice Block

The Twilio Voice block lets you initiate outbound calls, list call history, and retrieve details about a specific call through the Twilio Voice API. Reach for it whenever a workflow needs to trigger phone calls, audit call logs, or inspect individual call records programmatically.

Overview

When to Use

• Trigger an automated outbound phone call to a customer or contact as part of a notification or alert workflow.
• Play a dynamic TwiML message to a recipient by pointing the call to a URL that returns TwiML instructions.
• List recent calls on your Twilio account to feed a reporting or auditing downstream step.
• Fetch the full record for a specific call (by Call SID) to check status, duration, or direction.
• Chain call initiation with other workflow blocks — for example, first look up a phone number in a CRM block, then pass it to this block to make a call.
• Integrate voice calls into on-call incident response flows where a human-in-the-loop block precedes the call.

Configuration

Operation

Choose which Twilio Voice action the block performs. Defaults to Make call.

To

Phone number to call in E.164 format (e.g. +19998887777). Required for the Make call operation only.

From

Twilio phone number to call from in E.164 format (e.g. +15551234567). Required for the Make call operation only.

TwiML URL

A publicly accessible URL that returns TwiML instructions controlling what happens during the call (e.g. playing a message or connecting to an agent). Required for the Make call operation only.

Call SID

The unique SID (starts with CA) identifying the call to retrieve. Required for the Get call operation only.

Limit

Maximum number of call records to return. Optional for the List calls operation; defaults to Twilio's own page size when omitted.

Account SID

Your Twilio Account SID (starts with AC). Required for every operation. Stored as a password field — pass this via an environment variable reference such as {{TWILIO_ACCOUNT_SID}}.

Auth Token

Your Twilio Auth Token. Required for every operation. Stored as a password field — pass this via an environment variable reference such as {{TWILIO_AUTH_TOKEN}}.

Inputs & Outputs

• Inputs:

  • operation (string) — Operation to perform (twilio_voice_make_call, twilio_voice_list_calls, or twilio_voice_get_call)
  • accountSid (string) — Twilio Account SID
  • authToken (string) — Twilio Auth Token
  • To (string) — Number to call (Make call only)
  • From (string) — Twilio number to call from (Make call only)
  • Url (string) — TwiML instructions URL (Make call only)
  • callSid (string) — Call SID to retrieve (Get call only)
  • limit (number) — Result limit (List calls only)

• Outputs:

  • data (json) — Result object (Make call / Get call) or array of call objects (List calls) returned by Twilio
  • metadata (json) — Response metadata; contains sid (string) for Make call and Get call, or count (number) for List calls

Tools

• Twilio Make Call (twilio_voice_make_call) — Posts to the Twilio Calls API (POST /2010-04-01/Accounts/{AccountSid}/Calls.json) to initiate an outbound voice call. Requires To, From, and Url. Returns the full Twilio call object plus the Call SID in metadata.sid.
• Twilio List Calls (twilio_voice_list_calls) — Fetches the call list for the account (GET /2010-04-01/Accounts/{AccountSid}/Calls.json). Accepts an optional limit that maps to Twilio's PageSize query parameter. Returns an array of call objects in data and the count in metadata.count.
• Twilio Get Call (twilio_voice_get_call) — Retrieves a single call record by SID (GET /2010-04-01/Accounts/{AccountSid}/Calls/{CallSid}.json). Returns the full call object in data and the SID in metadata.sid.

YAML Example

twilio_voice_1:
  type: twilio_voice
  name: "Twilio Voice"
  inputs:
    operation: "twilio_voice_make_call"
    accountSid: "{{TWILIO_ACCOUNT_SID}}"
    authToken: "{{TWILIO_AUTH_TOKEN}}"
    To: "{{crm_lookup.phoneNumber}}"
    From: "+15551234567"
    Url: "https://example.com/twiml/welcome"
  connections:
    outgoing:
      - target: next-block-id