It's good that you have a "read" statement to force confirmation by the user of the command, but all it takes is one errant accidental enter to end up running arbitrary code returned from the LLM.
I'd constrain the tool to only run "ffmpeg" and extract the options/parameters from the LLM instead.
I'd constrain the tool to only run "ffmpeg" and extract the options/parameters from the LLM instead.