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Connect your Twilio account to run Text agents over SMS from your Twilio numbers. Messages go through your own Twilio account, so they use your numbers, your registrations (such as A2P 10DLC), and your Twilio logs. The same connection also powers Voice agents on those numbers.

Before you start

You need:
  • A Twilio account with at least one number that has SMS capability.
  • Your Twilio Account SID and Auth Token (Twilio Console → Account Info).
  • For US local (10-digit) numbers, an approved A2P 10DLC registration in Twilio. Toll-free numbers need toll-free verification. Carriers filter unregistered traffic.

Set up Twilio SMS

1

Connect Twilio in Callers

Open App Center, find Twilio, and connect it. In the Connect Twilio window, enter your Account SID and Auth Token. Set the Messages Per Second (MPS) Limit to the throughput Twilio has approved for your numbers (0.1–100, default 1), then click Connect. Full details are in Twilio integration.
2

Sync your numbers

Your Twilio numbers appear on the Phone numbers page and in the agent’s Channels window. Click Refresh to pull in numbers you bought after connecting.
3

Create a Text agent

Create an agent and pick SMS as the channel, or switch an existing agent to Text in General Settings.
4

Assign numbers

In the agent header click Channels → Text Channels, choose Twilio, and select one or more numbers. Save the agent.
5

Test and start

Click Test, enter your own mobile number, and click Start Chatting. When the chat looks right, start the agent.
When you save the agent, Callers sets each selected number’s incoming-message webhook to Callers and renames the number in Twilio to the agent ID and name. When you remove a number from the agent, Callers clears that webhook. If a number belongs to a Twilio Messaging Service that defines its own incoming-message handling, Twilio may route replies there instead. Remove the number from the service, or set the service to defer to the number’s own webhook.

Settings reference

Sending hours, follow-ups, chat window, and message delay are covered in Text agent settings.

Opt-outs

Callers follows Twilio’s opt-out handling. When a contact replies with an opt-out keyword such as STOP, the chat ends, the contact is marked Unsubscribed, and the agent stops messaging them. Twilio also blocks further messages to that number from your account until the contact replies with an opt-in keyword such as START. You manage the keywords and auto-replies in your Twilio account. See Text message opt-outs.
Only message people who have agreed to hear from you. See Compliance.

Troubleshooting

  • Check your Twilio balance and that the account is active.
  • Make sure the number has SMS capability.
  • For US local numbers, confirm your A2P 10DLC campaign is approved and the number is attached to it.
  • Open the message in the Twilio Console logs to see the carrier error code.
The contact previously replied STOP to your Twilio number (Twilio error 21610). They need to reply START before you can message them again.
Click Refresh on the Phone numbers page or in Channels. Check that the Account SID and Auth Token are correct and that the number has SMS capability.
Save the agent again so Callers re-applies the number’s webhook. Check that the number isn’t in a Messaging Service that overrides incoming-message handling.
Register for A2P 10DLC, keep the MPS limit at or below your approved throughput, and personalize messages with variables instead of sending identical text to everyone.

Twilio integration

Connection details shared by voice and SMS.

Text agent settings

Schedule, follow-ups, chat window, message delay.

Telnyx SMS

Use Telnyx numbers instead.

Twilio messaging docs

Registration, throughput, and error codes.