it was definitely a risky move, env vars are not perfect for this use-case (varargs is awkward) but I'm happy I went with the file tasks setup and the magic comments anyways. It's nice that you're not working in bash-inside-yaml or coming up with a new file type. It is just bash.

Agreed, and thank you. Every editor I personally use knows how to edit, highlight, and language server shell scripts. Zero of them, AFAICT, know how to do any of that with a shell script embedded in YAML.