**Example 1: To delete the description of a customer managed CMK**

The following ``update-key-description`` example deletes the description to a customer managed CMK.

* The ``--key-id`` parameter identifies the CMK in the command. This example uses a key ID value, but you can use either the key ID or the key ARN of the CMK. 
* The ``--description`` parameter with an empty string value ('') deletes the existing description. ::

    aws kms update-key-description \
        --key-id 0987dcba-09fe-87dc-65ba-ab0987654321 \
        --description ''

This command produces no output. To view the description of a CMK, use the the describe-key command.

For more information, see `UpdateKeyDescription <https://docs.aws.amazon.com/cli/latest/reference/kms/update-key-description.html>`__ in the *AWS Key Management Service API Reference*.

**Example 2: To add or change a description to a customer managed CMK**

The following ``update-key-description`` example adds a description to a customer managed CMK. You can use the same command to change an existing description. 

* The ``--key-id`` parameter identifies the CMK in the command. This example uses a key ARN value, but you can use either the key ID or the key ARN of the CMK. 
* The ``--description`` parameter specifies the new description. The value of this parameter replaces the current description of the CMK, if any. ::

    aws kms update-key-description \
        --key-id arn:aws:kms:us-west-2:123456789012:key/1234abcd-12ab-34cd-56ef-1234567890ab \
        --description "IT Department test key"

This command produces no output. To view the description of a CMK, use the ``describe-key`` command. 

For more information, see `UpdateKeyDescription <https://docs.aws.amazon.com/cli/latest/reference/kms/update-key-description.html>`__ in the *AWS Key Management Service API Reference*.