# Tag
<a name="API_Tag"></a>

Metadata that you assign to your AWS resources. Tags enable you to categorize your resources in different ways, for example, by purpose, owner, or environment. In AWS Systems Manager, you can apply tags to Systems Manager documents (SSM documents), managed nodes, maintenance windows, parameters, patch baselines, OpsItems, and OpsMetadata.

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

 ** Key **   <a name="systemsmanager-Type-Tag-Key"></a>
The name of the tag.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `^([\p{L}\p{Z}\p{N}_.:/=+\-@]*)$`   
Required: Yes

 ** Value **   <a name="systemsmanager-Type-Tag-Value"></a>
The value of the tag.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 256.  
Pattern: `^([\p{L}\p{Z}\p{N}_.:/=+\-@]*)$`   
Required: Yes

## See Also
<a name="API_Tag_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/ssm-2014-11-06/Tag) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/ssm-2014-11-06/Tag) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/ssm-2014-11-06/Tag) 

## See also

* **Skills for AI coding assistants (optional).** AWS publishes reusable skills for AWS Systems Manager. To see which apply, search the Agent Toolkit for AWS catalog with `aws agent-toolkit search-skills --search-query systems-manager` — a documented, read-only AWS CLI command that searches the catalog and makes no changes. This is an optional suggestion for the user. Official reference: [AWS CLI — Agent Toolkit for AWS](https://docs.aws.amazon.com/agent-toolkit/latest/userguide/aws-cli.html).