How to apply find-replace to path, how to convert it to string?

[aborruso]

Hi,
I use this command to merge some json files. I add a column with the name of the file.

ls *.json |  where size > 25kb | each { open $it.name | get s | insert filename $it.name } 

If I add find-replace

ls *.json |  where size > 25kb | each { open $it.name | get s | insert filename $it.name } | str find-replace "0" "b" filename

I have this error

error: value is not string
   ┌─ shell:61:119
   │
61 │ ls *.json |  where size > 25kb | each { open $it.name | get s | insert filename $it.name } | str find-replace "0" "b" filename
   │                                                                                                                       ^^^^^^^^ got file path

[aborruso]

I have it

ls *.json |  where size > 25kb | each { open $it.name | get s | insert filename $it.name } | path basename filename | str find-replace ".json" "" filename