Filter fuel tasks with non numeric ID shoud return significant error

I am trying to filter fuel Tasks.
When I passed task ID as a character then empty dictionary is returned. Its seems misleading.
Please find command below -

[root@fuel www]# fuel task
DEPRECATION WARNING: /etc/fuel/client/config.yaml exists and will be used as the source for settings. This behavior is deprecated. Please specify the path to your custom settings file in the FUELCLIENT_CUSTOM_SETTINGS environment variable.
id | status | name | cluster | progress | uuid
---|--------|------------------------------------|---------|----------|-------------------------------------
60 | ready | verify_networks | 6 | 100 | 9bea2319-3c54-4d60-bb98-26eb87fd0cd6
65 | ready | check_networks | 6 | 100 | 375a1470-1140-4b4c-8aac-5906987b140b
69 | ready | deployment | 6 | 100 | 803d73c8-f004-4a25-8b53-99c397434aa6
61 | ready | check_dhcp | 6 | 100 | d5540ddc-d9d5-430e-a34e-118b9094cb23
62 | ready | check_repo_availability | 6 | 100 | 414822b6-841e-4745-891a-d6366c7fdf3c
63 | ready | check_repo_availability_with_setup | 6 | 100 | 50eefec2-a1eb-4487-a67b-6e18a22974e8
68 | ready | provision | 6 | 100 | 7b056cc4-f39e-410d-aa60-ac9c0536e8fc
64 | ready | deploy | 6 | 100 | 61de6f38-b5af-4af8-be7f-e3d9c546f5a4

[root@fuel www]# fuel task --task 60
DEPRECATION WARNING: /etc/fuel/client/config.yaml exists and will be used as the source for settings. This behavior is deprecated. Please specify the path to your custom settings file in the FUELCLIENT_CUSTOM_SETTINGS environment variable.
id | status | name | cluster | progress | uuid
---|--------|-----------------|---------|----------|-------------------------------------
60 | ready | verify_networks | 6 | 100 | 9bea2319-3c54-4d60-bb98-26eb87fd0cd6
[root@fuel www]#

[root@fuel www]# fuel task --task z
DEPRECATION WARNING: /etc/fuel/client/config.yaml exists and will be used as the source for settings. This behavior is deprecated. Please specify the path to your custom settings file in the FUELCLIENT_CUSTOM_SETTINGS environment variable.
{}

[root@fuel www]# fuel task --delete --task z
DEPRECATION WARNING: /etc/fuel/client/config.yaml exists and will be used as the source for settings. This behavior is deprecated. Please specify the path to your custom settings file in the FUELCLIENT_CUSTOM_SETTINGS environment variable.
{}
[root@fuel www]#

For Non numeric task IDs it should return a valid significant error message.