This is the new *Amazon CloudFormation Template Reference Guide*. Please update your bookmarks and links. For help getting started with CloudFormation, see the [Amazon CloudFormation User Guide](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/Welcome.html).

# AWS::CloudWatch::MetricStream Tag
<a name="aws-properties-cloudwatch-metricstream-tag"></a>

A key-value pair associated with a CloudWatch resource.

## Syntax
<a name="aws-properties-cloudwatch-metricstream-tag-syntax"></a>

To declare this entity in your Amazon CloudFormation template, use the following syntax:

### JSON
<a name="aws-properties-cloudwatch-metricstream-tag-syntax.json"></a>

```
{
  "[Key](#cfn-cloudwatch-metricstream-tag-key)" : String,
  "[Value](#cfn-cloudwatch-metricstream-tag-value)" : String
}
```

### YAML
<a name="aws-properties-cloudwatch-metricstream-tag-syntax.yaml"></a>

```
  [Key](#cfn-cloudwatch-metricstream-tag-key): String
  [Value](#cfn-cloudwatch-metricstream-tag-value): String
```

## Properties
<a name="aws-properties-cloudwatch-metricstream-tag-properties"></a>

`Key`  <a name="cfn-cloudwatch-metricstream-tag-key"></a>
A string that you can use to assign a value. The combination of tag keys and values can help you organize and categorize your resources.  
*Required*: Yes  
*Type*: String  
*Minimum*: `1`  
*Maximum*: `128`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Value`  <a name="cfn-cloudwatch-metricstream-tag-value"></a>
The value for the specified tag key.  
*Required*: Yes  
*Type*: String  
*Minimum*: `0`  
*Maximum*: `256`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)