Enforce Formatting on Every File Edit
Your team requires all Python files to be formatted with Black before they're shared. You added a note in CLAUDE.md asking Claude to run Black after edits — but it occasionally skips it. That's expected: CLAUDE.md instructions are best-effort suggestions, not guarantees. A post-tool-use hook is different. It fires automatically after every file edit, every single time, with no exceptions.
The team's project is already in your working directory at /home/repl/climate-analysis/..
This exercise is part of the course
Claude Code 101
Exercise instructions
- Start Claude Code with
claude. - Ask Claude to add a post-tool-use hook to
settings.jsonthat runsblackon any Python file after it is edited. - When done, type
/exitto exit Claude Code.
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