Add custom parameters

Hello Guys.

i have a question for us.

I need to add a custom parameter in an app, but this should come from the moment the app was created in the cms.

For example:

i have de the app.

www.anydns/delivery/?sid=jshdjshjdhsdjshd&outhHash=LKJLKJ778KLJHKL7JHJKLHJKH

But I want to have

www.anydns/delivery/?code=504&sid=jshdjshjdhsdjshd&outhHash=LKJLKJ778KLJHKL7JHJKLHJKH

It is possible to add this parameter when the app is created in the cms.

Thanks in advance.

I will wait your answer.