We are using pre-commit as part of our python CI pipeline and often find we would like to use the really nice dependency management of pre-commit to include tools in various projects and invoke them in the terminal with arbitrary arguments.

Most of our tools are performing pure validation in the CI (we have a --validate flag we use with pre-commit) , but these tools expose other features useful to the developer.

Currently pre-commit only allows usage of the hook as a 'tool' in the terminal with

pre-commit run example-hook

If we wanted different arguments passed to different invocations this requires defining each permutation as a separate entry in the .pre-commit.config.yaml with specific predefined arguments in args:[...], which does not support using the hook as a tool with dynamic arguments.

Without having to have yet another solution to use our hooks as tools in the terminal, given pre-commit already provides 99% of the functionality we have added a --tool flag to our internal build of pre-commit.

--tool implies allow_all_files=true (this is a choice for our use cases but would work either way) and requires the hook is exposed for stages:["manual"].

A hook can be invoked as a tool with any arbitrary arguments using:

pre-commit run example-hook --tool -- --arg1 --arg2=4 ...