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AWS connect: Added dynamic source address configuration and WhatsApp support

Service: connect · 2026-07-29 · Documentation medium

File: connect/latest/adminguide/journey-flow-block-send-communication.md

Summary

Enhanced communication blocks to allow dynamic 'From' address configuration via attributes/Lambda and added WhatsApp message capabilities.

Security assessment

The change introduces dynamic source address configuration which could impact authentication trust if misconfigured, but doesn't address any specific vulnerability or add security guidance.

Evidence

+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key** that points to the ARN of a phone number claimed for your Amazon Connect instance.

Diff

diff --git a/connect/latest/adminguide/journey-flow-block-send-communication.md b/connect/latest/adminguide/journey-flow-block-send-communication.md
index 534431f0b..bec891202 100644
--- a//connect/latest/adminguide/journey-flow-block-send-communication.md
+++ b//connect/latest/adminguide/journey-flow-block-send-communication.md
@@ -7 +7 @@
-DescriptionContact typesHow to configure this blockSend an SMS (text message)Send an emailVoice call
+DescriptionContact typesHow to configure this blockSend an SMS (text message)Send a WhatsApp messageSend an emailVoice callHow to set From dynamically with Lambda
@@ -55 +55 @@ Property | Description
-From | Select the originating phone number or email address claimed for your instance.  
+From | Select the originating phone number or email address claimed for your instance. You can set this value manually or dynamically using an attribute.  
@@ -67,0 +68,4 @@ Configure the following properties on the page to send an SMS message:
+    * **Set manually** : Use the dropdown menu to select a phone number claimed for your Amazon Connect instance.
+
+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key** that points to the ARN of a phone number claimed for your Amazon Connect instance.
+
@@ -70 +74,20 @@ Configure the following properties on the page to send an SMS message:
-  * **Template alias or version** : Use the dropdown menu to choose different SMS template alias or version.
+  * **Template alias or version** : Use the dropdown menu to choose a different SMS template alias or version.
+
+  * **Store outbound communication** : You can choose to store outbound communication in flow attributes. By saving the outbound message ID in a flow attribute, you can track its delivery status.
+
+
+
+
+## Send a WhatsApp message
+
+Configure the following properties on the page to send a WhatsApp message:
+
+  * **From** : The phone number that the message is to be sent from. The dropdown menu shows a list of WhatsApp numbers that are imported into your Amazon Connect instance.
+
+    * **Set manually** : Use the dropdown menu to select a WhatsApp number imported into your Amazon Connect instance.
+
+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key** that points to the ARN of a WhatsApp number imported into your Amazon Connect instance.
+
+  * **Message template** : Use the dropdown menu to choose from a list of WhatsApp templates. You can choose one template to be sent to the customer.
+
+  * **Template alias or version** : Use the dropdown menu to choose a different WhatsApp template alias or version.
@@ -81 +104,9 @@ Configure the following properties on the page to send an email message:
-  * **From** : The email address that the message is to be sent from. The dropdown menu shows a list of email addresses that are claimed for your Amazon Connect instance.
+  * **From** : The email address that the message is to be sent from. The dropdown menu shows a list of email addresses that are configured for your Amazon Connect instance.
+
+    * **Set manually** : Use the dropdown menu to select an email address configured for your Amazon Connect instance.
+
+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key** that points to an email address configured for your Amazon Connect instance.
+
+  * **Display name** : Personalize how your email address appears to your customers in their inbox.
+
+    * **Set manually** : Enter the display name directly.
@@ -83 +114 @@ Configure the following properties on the page to send an email message:
-  * **Display name** : You can personalize how you email address appears to your customers in their inbox.
+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key**.
@@ -97,0 +129,6 @@ Configure the following properties on the page to use outbound voice channel:
+  * **From** : The phone number that the voice call is to be made from. The dropdown menu shows a list of phone numbers that are claimed for your Amazon Connect instance.
+
+    * **Set manually** : Use the dropdown menu to select a phone number claimed for your Amazon Connect instance.
+
+    * **Set dynamically** : Enter an attribute based on a **Namespace** and **Key** that points to the ARN of a phone number claimed for your Amazon Connect instance.
+
@@ -106,0 +144,29 @@ Configure the following properties on the page to use outbound voice channel:
+## How to set From dynamically with Lambda
+
+###### Pricing
+
+Custom action channel and Lambda pricing will apply.
+
+You can use an **Invoke Lambda** block earlier in the journey flow to determine the source phone number or email address at runtime. The **Send communication** block then references the returned value dynamically.
+
+### How it works
+
+  1. Add a [Custom action (Invoke Lambda)](./journey-flow-block-custom-action.html) block before the **Send communication** block in your journey flow.
+
+  2. The Lambda function runs and returns a JSON response that includes the source phone number or email address ARN in a key of your choice. For example:
+    
+        {
+      "sourcePhoneNumber": "arn:aws:connect:us-west-2:123456789012:phone-number/example-id"
+    }
+
+  3. The returned value becomes available in the flow at `$.LambdaInvocation.ResultData.`key``. In this example, the value is at `$.LambdaInvocation.ResultData.sourcePhoneNumber`.
+
+  4. In the **Send communication** block, set the **From** field to **Set dynamically** and reference the Lambda output. Set the **Namespace** to `Lambda invocation` and the **Key** to the field name your Lambda returns.
+
+![The From field set dynamically with Namespace set to Lambda invocation, Key set to Result data, and Attribute set to sourcePhoneNumber.](/images/connect/latest/adminguide/images/send-communication-dynamic-from-lambda.png)
+
+
+
+
+Your Lambda function can use any logic to determine the source address. Use any field name in the Lambda response, as long as it matches what you specify in the **From** field's dynamic reference.
+