SMS Channel

The SMS channel enables two-way text messaging with your bot through Telnyx. Users can interact with your bot by sending SMS messages to a dedicated phone number.

Prerequisites

• A Telnyx account with API credentials
• A provisioned phone number with SMS capability
• Telnyx integration configured in Settings > Integrations

Setup

1. Configure Telnyx Integration

Go to Settings > Integrations > Add Integration and select Telnyx:

Field	Description
API Key	Your Telnyx API v2 key
Messaging Profile ID	The Telnyx messaging profile to use
Public Key	Telnyx public key for webhook verification

imageTelnyx SMS integration configuration form showing API Key, Messaging Profile ID, and Public Key fields with a Test Connection button

Telnyx SMS integration setup

2. Provision a Phone Number

1. Navigate to your bot's Channels tab
2. Select SMS and click Configure
3. Choose Provision New Number or Use Existing Number
4. Select a number from available inventory (filter by area code or country)
5. Click Assign to Bot

TIP

You can assign the same phone number for both SMS and Voice channels. OmniBots routes incoming messages to the correct handler based on the message type.

3. Activate the Channel

Toggle the SMS channel to Active. OmniBots automatically configures the Telnyx webhook to point to your instance.

Message Handling

Feature	Details
Inbound SMS	Received and routed to the bot flow
Outbound SMS	Bot responses sent as SMS replies
MMS Images	Inbound images are stored and available as {{last_image_url}}
Character Limit	Messages over 160 characters are automatically segmented
Opt-Out	Users texting STOP are automatically unsubscribed
Opt-In	Users texting START are re-subscribed

imageMobile phone screen showing an SMS conversation with the bot, including user messages and bot text replies with numbered options

SMS bot conversation on a mobile phone

Conversation Threading

SMS conversations are threaded by phone number. If a user sends a message after the session timeout (default: 30 minutes), a new conversation is started.

Session timeout: 30 minutes (configurable per bot)
Thread key:      phone_number + bot_id

Compliance

WARNING

SMS messaging is subject to carrier regulations (TCPA in the US, GDPR in the EU). Ensure you have proper user consent before initiating outbound SMS and honor all opt-out requests.

OmniBots handles standard opt-out keywords (STOP, UNSUBSCRIBE, CANCEL, QUIT) automatically and logs compliance events for audit purposes.

Limitations

• Rich content (cards, carousels, forms) is converted to plain text with numbered options
• File uploads are limited to MMS-supported image formats
• Some carriers impose rate limits on high-volume messaging