# MessageStartEvent
<a name="API_runtime_MessageStartEvent"></a>

The start of a message.

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

 ** role **   <a name="bedrock-Type-runtime_MessageStartEvent-role"></a>
The role for the message.  
Type: String  
Valid Values: `user | assistant`   
Required: Yes

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

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/bedrock-runtime-2023-09-30/MessageStartEvent) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/bedrock-runtime-2023-09-30/MessageStartEvent) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/bedrock-runtime-2023-09-30/MessageStartEvent)