Guidelines and requirements - Amazon Personalize
Additional information
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Guidelines and requirements

Each tag consists of a required tag key and an optional tag value, both of which you define. A tag key is a general label that acts as a category for more specific tag values. A tag value acts as a descriptor for a tag key.

For example, if you have two versions of an Amazon Personalize dataset group (one for internal testing and another for production), you might assign an Environment tag key to both projects. The tag value of the Environment tag might be Test for one version of the dataset group and Production for the other version.

The following restrictions apply to tags:

  • Maximum number of tags per resource – 50

  • Maximum key length – 128 Unicode characters in UTF-8

  • Maximum value length – 256 Unicode characters in UTF-8

  • Tag keys and values can contain the following characters: A-Z, a-z, 0-9, space, and _ . : / = + @ – (hyphen). This is the standard set of characters available across Amazon services that support tags. Some services support additional symbols.

  • Tag keys and tag values are case sensitive.

  • For each associated resource, each tag key must be unique and it can have only one tag value.

  • Your tag keys and tag values can't start with aws:. Amazon services apply tags that start with aws:, and those tags can't be modified. They don't count towards tag limits.

  • You can't update or delete a resource based only on its tags. You must also specify the Amazon Resource Name (ARN) or resource ID, depending on the operation that you use.

Additional information

For more information about tagging, see the following resources.