Claude Code hooks builder

{
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Bash|PowerShell",
        "hooks": [
          {
            "type": "command",
            "command": "\"$CLAUDE_PROJECT_DIR\"/.claude/hooks/block-rm.sh",
            "timeout": 30,
            "onFailure": "block"
          }
        ]
      },
      {
        "matcher": "Edit|Write",
        "hooks": [
          {
            "type": "command",
            "command": "\"$CLAUDE_PROJECT_DIR\"/.claude/hooks/protect-files.sh",
            "timeout": 30,
            "onFailure": "block"
          }
        ]
      }
    ]
  }
}

#!/bin/bash
# block-rm.sh: Claude Code PreToolUse hook for the Bash and PowerShell tools.
# Blocks recursive deletes: rm -r, rm -rf, rm --recursive, Remove-Item -Recurse
# (and its aliases), rmdir /s. Exit 2 blocks the call; Claude reads stderr.
# Fails closed: if the input can't be read, the command is blocked.

block() {
  echo "Blocked by the block-rm hook: $1" >&2
  exit 2
}

command -v jq >/dev/null 2>&1 || block "jq is not installed, so the command couldn't be checked. Install jq: https://jqlang.org/download/"
input=$(cat)
cmd=$(jq -r '.tool_input.command // empty' <<<"$input" 2>/dev/null) || block "the hook input wasn't valid JSON."
[ -n "$cmd" ] || exit 0
cmd=${cmd//[\"\'\\^]/}   # drop quotes, backslashes and carets, so "rm", r''m and \rm count as rm

shopt -s nocasematch
nl=$'\n'
rest="([[:space:]][^;&|$nl]*)?[[:space:]]"   # more words of the same command
patterns=(
  "(^|[^[:alnum:]_.-])rm$rest(-[[:alpha:]]*r[[:alpha:]]*|--r[[:alpha:]-]*)([^[:alnum:]-]|$)"
  "(^|[^[:alnum:]_-])(remove-item|ri|rd|rmdir|del|erase)$rest-r(e|ec|ecu|ecur|ecurs|ecurse)?([^[:alnum:]-]|$)"
  "(^|[^[:alnum:]_-])(rmdir|rd|del|erase)$rest/s([^[:alnum:]]|$)"
)
for re in "${patterns[@]}"; do
  if [[ $cmd =~ $re ]]; then
    block "recursive deletes aren't allowed (found: ${BASH_REMATCH[0]}). Delete specific files, or ask the user to run it."
  fi
done
exit 0

#!/bin/bash
# protect-files.sh: Claude Code PreToolUse hook for the Edit and Write tools.
# Blocks edits to protected files. Exit 2 blocks the edit; Claude reads stderr.
# Fails closed: no jq, or input it can't read, also blocks.

# File names (glob patterns), directories, and names that stay editable.
protected_names=('.env' '.env.*' '*.pem' '*.key')
protected_dirs=('.git' 'secrets')
allowed_names=('.env.example')

block() {
  echo "Blocked by the protect-files hook: $1" >&2
  exit 2
}

command -v jq >/dev/null 2>&1 || block "jq is not installed, so the edit couldn't be checked. Install jq: https://jqlang.org/download/"
input=$(cat)
file=$(jq -r '.tool_input.file_path // empty' <<<"$input" 2>/dev/null) || block "the hook input wasn't valid JSON."
[ -n "$file" ] || block "the hook input had no file path."
# Compare the path as Windows resolves it: forward slashes, no trailing dots or
# spaces on a name (.env. and ".env " are .env) and no :stream suffix.
check=$(sed -E 's#\\#/#g; s#:[^/]*$##; s#[. ]+(/|$)#\1#g' <<<"/$file") && [ -n "$check" ] || block "the file path couldn't be checked."
name=${check##*/}
shopt -s nocasematch   # .ENV and .env are the same file on Windows and macOS

for d in "${protected_dirs[@]}"; do
  [[ $check == */"$d"/* ]] && block "$file is inside $d/, which is protected. Ask the user to change it by hand."
done
for n in "${allowed_names[@]}"; do
  [[ $name == $n ]] && exit 0
done
for n in "${protected_names[@]}"; do
  [[ $name == $n ]] && block "$file is protected ($n). Ask the user to change it by hand."
done
exit 0