# Message
<a name="API_Message"></a>

A message in a conversation, either from the user or the assistant.

## Contents
<a name="API_Message_Contents"></a>

**Important**  
This data type is a UNION, so only one of the following members can be specified when used or returned.

 ** assistantMessage **   <a name="devopsagent-Type-Message-assistantMessage"></a>
A message from the assistant.  
Type: Array of [AssistantMessageBlock](API_AssistantMessageBlock.md) objects  
Required: No

 ** userMessage **   <a name="devopsagent-Type-Message-userMessage"></a>
A message from the user.  
Type: Array of [UserMessageBlock](API_UserMessageBlock.md) objects  
Required: No

## See Also
<a name="API_Message_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\+\+](https://docs.aws.amazon.com/goto/SdkForCpp/devops-agent-2026-01-01/Message) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/devops-agent-2026-01-01/Message) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/devops-agent-2026-01-01/Message)