**To decode an encoded authorization message returned in response to a request**

The following ``decode-authorization-message`` example decodes additional information about the authorization status of a request from an encoded message returned in response to an Amazon Web Services request. ::

    aws sts decode-authorization-message \
        --encoded-message  

Output::

    {
        "DecodedMessage": "{\"allowed\":false,\"explicitDeny\":true,\"matchedStatements\":{\"items\":[{\"statementId\":\"VisualEditor0\",\"effect\":\"DENY\",\"principals\":{\"items\":[{\"value\":\"AROA123456789EXAMPLE\"}]},\"principalGroups\":{\"items\":[]},\"actions\":{\"items\":[{\"value\":\"ec2:RunInstances\"}]},\"resources\":{\"items\":[{\"value\":\"*\"}]},\"conditions\":{\"items\":[]}}]},\"failures\":{\"items\":[]},\"context\":{\"principal\":{\"id\":\"AROA123456789EXAMPLE:Ana\",\"arn\":\"arn:aws:sts::111122223333:assumed-role/Developer/Ana\"},\"action\":\"RunInstances\",\"resource\":\"arn:aws:ec2:us-east-1:111122223333:instance/*\",\"conditions\":{\"items\":[{\"key\":\"ec2:MetadataHttpPutResponseHopLimit\",\"values\":{\"items\":[{\"value\":\"2\"}]}},{\"key\":\"ec2:InstanceMarketType\",\"values\":{\"items\":[{\"value\":\"on-demand\"}]}},{\"key\":\"aws:Resource\",\"values\":{\"items\":[{\"value\":\"instance/*\"}]}},{\"key\":\"aws:Account\",\"values\":{\"items\":[{\"value\":\"111122223333\"}]}},{\"key\":\"ec2:AvailabilityZone\",\"values\":{\"items\":[{\"value\":\"us-east-1f\"}]}},{\"key\":\"ec2:ebsOptimized\",\"values\":{\"items\":[{\"value\":\"false\"}]}},{\"key\":\"ec2:IsLaunchTemplateResource\",\"values\":{\"items\":[{\"value\":\"false\"}]}},{\"key\":\"ec2:InstanceType\",\"values\":{\"items\":[{\"value\":\"t2.micro\"}]}},{\"key\":\"ec2:RootDeviceType\",\"values\":{\"items\":[{\"value\":\"ebs\"}]}},{\"key\":\"aws:Region\",\"values\":{\"items\":[{\"value\":\"us-east-1\"}]}},{\"key\":\"ec2:MetadataHttpEndpoint\",\"values\":{\"items\":[{\"value\":\"enabled\"}]}},{\"key\":\"aws:Service\",\"values\":{\"items\":[{\"value\":\"ec2\"}]}},{\"key\":\"ec2:InstanceID\",\"values\":{\"items\":[{\"value\":\"*\"}]}},{\"key\":\"ec2:MetadataHttpTokens\",\"values\":{\"items\":[{\"value\":\"required\"}]}},{\"key\":\"aws:Type\",\"values\":{\"items\":[{\"value\":\"instance\"}]}},{\"key\":\"ec2:Tenancy\",\"values\":{\"items\":[{\"value\":\"default\"}]}},{\"key\":\"ec2:Region\",\"values\":{\"items\":[{\"value\":\"us-east-1\"}]}},{\"key\":\"aws:ARN\",\"values\":{\"items\":[{\"value\":\"arn:aws:ec2:us-east-1:111122223333:instance/*\"}]}}]}}}"
    }

For more information, see `Policy evaluation logic <https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_evaluation-logic.html>`__ in the *AWS IAM User Guide*.