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This section details on the original issue you should resolve

<issue_title>Difference versus pre-commit: prek inherits UV_RESOLUTION from the environment when installing hooks</issue_title>
<issue_description>When UV_RESOLUTION=lowest-direct is set in the environment (e.g., for testing a project's dependencies with lowest compatible versions), prek passes this through to uv when installing hooks.

This causes hook dependencies to resolve to ancient versions that may not build on modern Python. For example, pre-commit-hooks depends on ruamel-yaml, and with lowest-direct resolution, uv picks ruamel-yaml==0.15.0 (from 2017), which fails to build on Python 3.12+ with:

NameError: name 'Str' is not defined

Reproduction:

UV_RESOLUTION=lowest-direct UV_PYTHON=3.12 prek run --all-files --hook-stage pre-commit

With a .pre-commit-config.yaml that uses https://github.com/pre-commit/pre-commit-hooks

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Either this behaviour should be changed in prek, or https://prek.j178.dev/quickstart/#already-using-pre-commit should mention it.</issue_description>

<agent_instructions>Mention uv environments would affect prek (because prek calls uv underhook to create Python venv and install Python deps) in diff.md</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@j178 UV already has a ton of environment‑variable knobs, and there are going to be more. Since everything can affect the UV that’s run by prek, it’s basically impossible to document every single one.