Does pants automatically set up file watcher for all files in the directory when issuing a command? I'm running into issues with

MaxFilesWatch

in our CI environment, even when running a basic

pants run ...

on a small PEX.

Yes it watches all files that are not ignored

Is there a reason for this to be the case even when pants is not run with

--loop

?

Yes because it needs to invalidate commands that depend on the files involved if they change

if you don't need this invalidation during CI, you can run with file watching disabled.. https://www.pantsbuild.org/docs/reference-global#watch_filesystem