If you add a Capacity Reservation that is shared with you to a group, and that Capacity Reservation is unshared, it is automatically removed from the group.
To add a Capacity Reservation to a group
Use the group-resources
The following example adds two Capacity Reservations to the specified group.
aws resource-groups group-resources \ --group
MyCRGroup
\ --resource-arns \ arn:aws:ec2:sa-east-1
:123456789012
:capacity-reservation/cr-1234567890abcdef1
\ arn:aws:ec2:sa-east-1
:123456789012
:capacity-reservation/cr-54321abcdef567890