awscli.json

$ aws cloudformation list-stack-resources --stack-name $stack_name --query "StackResourceSummaries[][?ResourceType=='AWS::EC2::Instance'][]" --region $reg --profile $acct
[]
$ aws cloudformation list-stack-resources --stack-name $stack_name --query "StackResourceSummaries[][?ResourceType=='AWS::EC2::Instance'][*]" --region $reg --profile $acct
[]
$ aws cloudformation list-stack-resources --stack-name $stack_name --query 'StackResourceSummaries[*][?contains(ResourceType,`Instance`) == true].[ResourceType,ResourceStatus,LogicalResourceId]' --region $reg --profile $acct
[]

example.json

$ aws cloudformation list-stack-resources --stack-name $stack_name --region $reg --profile $acct
{
    "StackResourceSummaries": [
        {
            "ResourceType": "AWS::EC2::Instance",
            "PhysicalResourceId": "i-0fed57248f4f716b3",
            "LastUpdatedTimestamp": "2018-10-29T21:56:43.420Z",
            "ResourceStatus": "CREATE_COMPLETE",
            "LogicalResourceId": "ADDC01"
        },
        {
            "ResourceType": "AWS::CloudWatch::Alarm",
            "PhysicalResourceId": "cf-teo-active-directory-ADDC01CPUAlarm-XRX2LLZSIV6H",
            "LastUpdatedTimestamp": "2018-10-29T21:57:03.651Z",
            "ResourceStatus": "CREATE_COMPLETE",
            "LogicalResourceId": "ADDC01CPUAlarm"
        },
...