modify documents

Writing/Gemini/.codex/hooks/pre_tool_guard.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+"""Codex PreToolUse guard for obviously destructive shell commands."""
+
+import json
+import re
+import sys
+from typing import Any
+
+
+DANGEROUS_PATTERNS = [
+    (r"\brm\s+-rf\b", "Recursive force deletion is blocked by the document harness."),
+    (
+        r"\bRemove-Item\b(?=.*\b-Recurse\b|\s-r\b)(?=.*\b-Force\b|\s-f\b)",
+        "PowerShell recursive force deletion is blocked by the document harness.",
+    ),
+    (r"\bgit\s+reset\s+--hard\b", "Hard reset is blocked because it can discard user work."),
+    (r"\bgit\s+push\b.*\s--force(?:-with-lease)?\b", "Force push is blocked by the document harness."),
+    (r"\bDROP\s+TABLE\b", "Destructive database commands are blocked by the document harness."),
+]
+
+
+def iter_strings(value: Any):
+    if isinstance(value, str):
+        yield value
+    elif isinstance(value, dict):
+        for key, item in value.items():
+            yield str(key)
+            yield from iter_strings(item)
+    elif isinstance(value, list):
+        for item in value:
+            yield from iter_strings(item)
+
+
+def deny(reason: str) -> None:
+    payload = {
+        "hookSpecificOutput": {
+            "permissionDecision": "deny",
+            "permissionDecisionReason": reason,
+        },
+        "decision": "block",
+        "reason": reason,
+    }
+    print(json.dumps(payload, ensure_ascii=False))
+
+
+def main() -> int:
+    raw = sys.stdin.read()
+    haystack = raw
+
+    try:
+        data = json.loads(raw) if raw.strip() else {}
+    except json.JSONDecodeError:
+        data = {}
+
+    if data:
+        haystack += "\n" + "\n".join(iter_strings(data))
+
+    for pattern, reason in DANGEROUS_PATTERNS:
+        if re.search(pattern, haystack, flags=re.IGNORECASE | re.DOTALL):
+            deny(reason)
+            return 0
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())