Why do not return ok if the group aready exists?

[NoWait126]

When we use xgroup create testStream goup1 $ to create goup1, we will get ok if successful, or we will get error if failed. It will return an error for redisexceptions or if the group already exists. For the group already exists, the error message is like BUSYGROUP Consumer Group name already exists. It looks like no problem，but for cluster deployment or service restart, we will get this error message tells us the group is already exists. Such as:
1 Server A has been started and created group1, then server B is starting and begin to create group1, server B will get error.
2 Server A has been started and created group1, then Server A restart for some reason, it will also get error when create group1.

So why donot return ok if the group aready exists?

[itamarhaber]

Hello @NoWait126

The creation of a consumer group also sets the ID for the group (0-0, last or any arbitrary value). The error prevents overwriting this information.

[NoWait126]

Hello @itamarhaber
If this, I should judge the error message, the pseudo code is as follows

msg = xgroup create testStream goup1 $
if msg == "ok" || msg.contain_substring("exists") {
    it is ok , we can use the group
} else {
    something error in redis, we can not use group,  should return
}

I am not sure if my understanding is correct, please correct me, thanks