Tell HN: Git hook to keep LLM signatures out of your commit history

I’ve noticed a trend where LLMs append Co-authored-by: [AI Name] to the end of commit messages. Even if you try to prompt it away, context drift or new sessions eventually lead to one slipping through into the codebase.

I’m using a git hook to prevent any of that from reaching my commits instead of relying on LLMs.

  #!/bin/sh
  if grep -qi "co-authored-by" "$1"; then
    echo "error: commit message contains 'Co-authored-by'. Commit rejected." >&2
    exit 1
  fi