Twilio SMS Block

The Twilio SMS block sends text messages to single or multiple recipients using the Twilio API. Reach for it whenever a workflow needs to notify people by SMS — such as alerts, confirmations, one-time codes, or status updates.

Overview

When to Use

• Send transactional alerts (order updates, payment receipts, status changes) to a customer's phone.
• Deliver one-time passcodes or verification codes as part of an authentication or approval workflow.
• Notify an on-call engineer or team member when an automated process detects a failure.
• Send appointment reminders or confirmations triggered by a schedule or form submission.
• Broadcast a message to multiple recipients by listing several phone numbers, one per line.
• Integrate SMS into multi-channel notification pipelines alongside email or Slack.

Configuration

Recipient Phone Numbers

The phone numbers to send the SMS to, in E.164 format (e.g. +1234567890). Enter one phone number per line to send to multiple recipients. Required.

Note: The underlying tool sends to the first phone number in the list per API call. To message multiple recipients, chain multiple blocks or handle the list upstream.

Message

The body text of the SMS message. Required. Supports dynamic values injected via {{blockName.field}} references from upstream blocks.

Twilio Account SID

Your Twilio Account SID, available in the Twilio Console. Used to identify your account for API authentication. Required.

Auth Token

Your Twilio Auth Token, available in the Twilio Console. Stored and handled as a password (masked in the UI). Required. Use an environment variable reference such as {{TWILIO_AUTH_TOKEN}} to avoid hardcoding credentials.

From Twilio Phone Number

The Twilio phone number to send the message from, in E.164 format (e.g. +1987654321). This must be a number purchased and configured in your Twilio account. Required.

Inputs & Outputs

• Inputs:

  • phoneNumbers (string) — Recipient phone numbers, one per line in E.164 format (e.g. +1234567890)
  • message (string) — SMS message text to send
  • accountSid (string) — Twilio Account SID for API authentication
  • authToken (string) — Twilio Auth Token for API authentication
  • fromNumber (string) — Twilio phone number to send the message from

• Outputs:

  • success (boolean) — Whether the SMS was sent successfully
  • messageId (string) — Unique Twilio message SID returned after a successful send
  • status (string) — SMS delivery status from Twilio (e.g. queued, sent, delivered, failed)
  • error (string) — Error information if sending fails

Tools

Twilio Send SMS (twilio_send_sms) — Sends an SMS via the Twilio Messages API (POST /2010-04-01/Accounts/{AccountSid}/Messages.json). Authenticates with HTTP Basic Auth using the Account SID and Auth Token. Accepts the recipient number, sender number, and message body, then returns the Twilio message SID and delivery status.

YAML Example

twilio_sms_1:
  type: twilio_sms
  name: "Send Alert SMS"
  inputs:
    phoneNumbers: "+1234567890"
    message: "Alert: {{monitor_block.alertMessage}}"
    accountSid: "{{TWILIO_ACCOUNT_SID}}"
    authToken: "{{TWILIO_AUTH_TOKEN}}"
    fromNumber: "+1987654321"
  connections:
    outgoing:
      - target: next-block-id