cc-read-limit-hook

A Claude Code PreToolUse hook that enforces file read limits to optimize context usage.

一个 Claude Code PreToolUse 钩子，用于限制文件读取范围以优化上下文使用。

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Features / 功能

• Block large file reads - Files >1000 lines or >50KB require offset + limit parameters
• Limit single reads - Max 500 lines / 20KB per read operation
• Auto-add limit - Automatically adds limit when only offset is specified
• Statistics logging - Logs read attempts for analysis

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• 阻止大文件读取 - 超过 1000 行或 50KB 的文件必须指定 offset + limit 参数
• 限制单次读取 - 每次最多读取 500 行 / 20KB
• 自动添加 limit - 仅指定 offset 时自动补充 limit
• 统计日志 - 记录读取操作用于分析

Installation / 安装

1. Copy read-guard.py to your hooks directory:

   cp read-guard.py "$USERPROFILE/.claude/hooks/"

2. Add to ~/.claude/settings.json:

   {
     "hooks": {
       "PreToolUse": [
         {
           "matcher": "Read",
           "hooks": [
             {
               "type": "command",
               "command": "python \"$USERPROFILE/.claude/hooks/read-guard.py\""
             }
           ]
         }
       ]
     }
   }

Configuration / 配置

Edit the constants in read-guard.py:

MAX_FILE_LINES = 1000        # Line threshold / 行数阈值
MAX_FILE_BYTES = 50 * 1024   # Byte threshold / 字节阈值
MAX_SINGLE_READ_LINES = 500  # Max lines per read / 单次最大行数
MAX_SINGLE_READ_BYTES = 20 * 1024  # Max bytes per read / 单次最大字节

License / 许可

MIT