What exactly do you mean with "description"?

A description field is required to understand what this is for.

Now:

set protocols static route 1.1.1.1/32 next-hop 10.1.0.34 distance '5'
set protocols static route 146.158.52.0/22 next-hop 10.1.0.25 distance '5'

with description:

set protocols static route 1.1.1.1/32 next-hop 10.1.0.34 distance '5'
set protocols static route 1.1.1.1/32 description "1.1.1.1 via serverius"
set protocols static route 146.158.52.0/22 next-hop 10.1.0.25 distance '5'
set protocols static route 1.1.1.1/32 description "avito AS via vector.spb"

There is yet no intention to add such command. Usually all description strings are rendered into the appropriate configuration file or are added to the interface as alias used by SNMP monitoring. What you wish to do is actually commenting on your configuration. Please refer to the user-guide about the comment command.

https://docs.vyos.io/en/latest/configuration-overview.html#comment