[xnx]

You can probably achieve what you want with https://github.com/simonw/llm and a little bit of command line.

Not sure what OS you're on, but in Windows it might look like this:

FOR %%F IN (*.txt) DO (TYPE "%%F" | llm -s "execute this prompt" >> "output.txt)

[WillAdams]

I want to work with PDFs (or JPEGs), but that should be a start, I hope.

[xnx]

llm supports attachments too

FOR %%F IN (*.pdf) DO (llm -a %%F -s "execute this prompt" >> output.txt)