SMS

Once a Twilio phone number is connected to your project, incoming text messages are automatically routed to your agent. Inbound SMS is the channel: people text your number and your agent replies. To send an SMS from a chat or voice conversation, use the Twilio tool.

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How it works

When someone texts your connected phone number, Voiceflow routes the message based on how the number is configured for SMS:

• Assigned to an environment: every message goes to that environment, using either its Published (live) version or its Draft, depending on which you picked when assigning.
• Unassigned: messages follow the traffic split configured in Settings → Environments, just like chat sessions, phone calls, and API conversations.

SMS assignment is independent of voice assignment. A number can route calls to one environment and texts to another. To change a number’s SMS assignment, click the environment label next to the number in the Phone numbers tab. See Routing SMS to an environment for the full flow.

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Sender identification

When a text comes in, the sender’s phone number is automatically set as the user_id variable. This lets you identify returning users and personalize conversations based on their information.

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Testing draft changes by SMS

While you’re working on a change, point a non-production phone number at the environment’s draft version. Texts to that number use your unpublished work, so you can message in and verify the change yourself before publishing. A phone number that real users text should never be pointed at a draft.

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Testing changes with real users

When you want to validate a change against Main using real message data, use a traffic split. Clone Main, make and publish your change in the new environment, then route a small percentage of SMS traffic to it. Compare the results in Analytics and Transcripts, and once you’re confident, merge the environment back into Main.