keyId 
  Updates the description of the specified KMS key.
Specify the key ID or key ARN of the KMS key.
For example:
- Key ID: - 1234abcd-12ab-34cd-56ef-1234567890ab
- Key ARN: - arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab
To get the key ID and key ARN for a KMS key, use ListKeys or DescribeKey.