Messaging Setup (Retell)

Overview

A messaging connection lets your Retell AI agent handle text-based conversations — inbound SMS, WhatsApp, Instagram DMs, Facebook messages, webchat, and more. The AI reads each message, generates a response, and sends it back through GHL Conversations.

Need a Retell account?Use this Retell link. Sign up through this link.RetellAI.com

Messaging connections are separate from voice connections. If your agent handles both calls and messages, create one voice connection and one messaging connection.

Create a Retell messaging connection

Open the Retell page

In the Sympana dashboard, click Retell.

Switch to Messaging

Click the Messaging tab at the top (next to Voice).

Click Add Messaging Connection

Click the button to create a new messaging connection.

Name your connection

Give it a clear name like “SMS Support Agent” or “Instagram Sales Bot.”

Select your Retell messaging agent

Choose the Retell agent that will handle messages. This should be an agent configured for text conversations.

Link a GHL calendar (optional)

Only needed if the messaging agent uses appointment functions (Book Appointment, Get Slots, etc.).

Configure Contact Access

Control who the AI is allowed to message:

Setting	What it does
Allowed Tags	Only contacts with these tags get AI replies
Blocked Tags	Contacts with these tags are skipped
Handoff Tags	Contacts with these tags are treated as handed-off to a human
Opt-out Keywords	Words like “stop”, “unsubscribe” — AI stops replying

Select functions

Enable the functions your messaging agent needs — same 11 functions as voice (Book Appointment, Get Contact, Update Contact Data, etc.).

Configure dynamic variables

Add variables the agent needs — contact name, email, custom fields, etc.

Configure Human Handoff

Set up handoff keywords. When a contact says “talk to a person” or “human”, the AI stops and fires the Handoff Requested trigger in GHL.

Save

Click Save. The connection is now available for GHL workflows.

Build a messaging workflow

After creating the connection, build a GHL workflow to use it:

Trigger: Message Received (Sympana)
  → Optional: Filter by channel (SMS, WhatsApp, Instagram, etc.)
  → Optional: If/Else — Contact has tag "ai_msg_enabled"
  → Action: Send AI Message (Sympana) — select your Retell messaging connection

Channel filtering belongs in the GHL trigger, not in the messaging connection. The connection is channel-agnostic — GHL decides which messages to route to AI.

Build a handoff workflow

Trigger: Handoff Requested (Sympana)
  → Action: Add Tag "ai_msg_handoff"
  → Action: Assign contact to team member
  → Action: Send internal notification to your team
  → Optional: Create Task "Follow up with {{contact_first_name}}"

Recommended tag strategy

Tag	When to apply
`ai_msg_enabled`	When you outbound a contact or opt them in for AI messaging
`ai_msg_blocked`	When the contact opts out (says “stop”, “unsubscribe”)
`ai_msg_handoff`	When handoff is triggered — AI pauses

Test your messaging connection

Make sure the messaging connection is active in Sympana
Publish the Message Received workflow in GHL
Send a test inbound message (SMS or other channel) to your GHL number
Verify the AI responds in GHL Conversations
Test handoff by sending a handoff keyword (e.g., “I want to talk to a person”)
Verify the Handoff Requested workflow fires

If the AI doesn’t respond, check: Is the workflow published? Does the contact have the required tags? Is the connection active? Is the Retell API key valid?

Connect

Actions

Functions

Messaging

Overview

Create a Retell messaging connection

Build a messaging workflow

Build a handoff workflow

Recommended tag strategy

Test your messaging connection

Next steps

Messaging Connection Setup

Workflow Recipes

​Overview

​Create a Retell messaging connection

​Build a messaging workflow

​Build a handoff workflow

​Recommended tag strategy

​Test your messaging connection

​Next steps

Messaging Connection Setup

Workflow Recipes

Overview

Create a Retell messaging connection

Build a messaging workflow

Build a handoff workflow

Recommended tag strategy

Test your messaging connection

Next steps