Transmission completed torrent script not being run

I’m trying to run a script on completion of a torrent download. I configured Transmission with the following lines in settings.json:

    "script-torrent-done-enabled": true,
    "script-torrent-done-filename": "/mnt/dietpi_userdata/scripts/",

but the script is apparently not being run
What I already tried:

  • the script runs if I launch it from the prompt
  • did chmod +x to allow anyone to run it
  • transmission-daemon is run as root, so it should not be a permission issue
  • replaced the content of the script with a very simple “touch test.txt”, and the file is not created
  • other parameters that I changed in settings.json are correctly being interpreted
  • added “PATH:$PATH:/usr/bin” at the beginning of the script, in case the commands used in the script were not found

In the past I’ve been able to run similar scripts (probably in raspbian, not dietpi if I remember well).
Any suggestion?