Hooks

Where it lives

• hooks/preflight_hook.pyGitHub ↗
  Read the script

  # -*- coding: utf-8 -*-
  # Author: dengwanpeng
  
  """Claude Code PreToolUse hook：在 AI 调用 Skill 工具触发 api-test-E10 时，
  自动执行 tools/preflight_check.py，把输出通过 hookSpecificOutput.additionalContext
  注入 AI 上下文，等价于 SKILL.md 里原本的「前置必跑 0」。
  
  Hook I/O 协议（Claude Code 标准）：
  - stdin:  JSON {tool_name, tool_input: {skill, args?}, cwd, session_id, ...}
  - stdout: JSON {hookSpecificOutput: {hookEventName, additionalContext}}
  - exit 0: 放行；exit 2: 阻断该工具调用
  
  ⚠️ 触发范围限制：仅在 AI 主动调 `Skill({skill: "api-test-E10"})` 时生效；
     被 `Read` / `@skill_path` / system-reminder 触发的 skill 加载不会进入这里。
  """
  
  import json
  import os
  import subprocess
  import sys
  
  HOOK_DIR = os.path.dirname(os.path.abspath(__file__))
  SKILL_ROOT = os.path.dirname(HOOK_DIR)
  PREFLIGHT_SCRIPT = os.path.join(SKILL_ROOT, "tools", "preflight_check.py")
  
  for _stream in (sys.stdout, sys.stderr):
      try:
          _stream.reconfigure(encoding="utf-8")
      except (AttributeError, ValueError):
          pass
  
  
  def main() -> int:
      try:
          payload = json.load(sys.stdin)
      except Exception:
          return 0
  
      tool_input = payload.get("tool_input") or {}
      skill_name = (tool_input.get("skill") or "").strip()
  
      # 只拦截 api-test-E10，避免影响其他 Skill。
      should_run = skill_name == "api-test-E10"
  
      if not should_run:
          return 0
  
      cwd = payload.get("cwd") or os.getcwd()
      env = os.environ.copy()
      env["PYTHONIOENCODING"] = "utf-8"
  
      try:
          result = subprocess.run(
              [sys.executable, PREFLIGHT_SCRIPT],
              cwd=cwd,
              text=True,
              encoding="utf-8",
              env=env,
              capture_output=True,
              timeout=120,
          )
      except Exception as e:
          # preflight 自身崩溃（脚本路径错 / 超时 / Python 缺失），不要阻断 skill
          err_ctx = f"[preflight_hook] 执行 preflight_check.py 失败: {e}"
          print(json.dumps({
              "hookSpecificOutput": {
                  "hookEventName": "PreToolUse",
                  "additionalContext": err_ctx,
              }
          }, ensure_ascii=False))
          return 0
  
      output_blob = (result.stdout or "") + (result.stderr or "")
      context_text = (
          "[preflight_check] 入口前置检查结果（由 hook 自动执行，等价于 SKILL.md 原前置必跑 0）：\n"
          + output_blob.strip()
      )
      print(json.dumps({
          "hookSpecificOutput": {
              "hookEventName": "PreToolUse",
              "additionalContext": context_text,
          }
      }, ensure_ascii=False))
  
      # preflight 失败只把诊断注入上下文，不阻断 Skill 调用。
      if result.returncode != 0:
          return 0
  
      return 0
  
  
  if __name__ == "__main__":
      sys.exit(main())
  

Read the script before you install anything that runs on your machine. This is the one part of a plugin that acts without being asked.