Auto-Load Your Dev Environment When Changing Directories

If you use direnv to manage per-project environment variables, Claude Code won't automatically pick up those environments when you switch directories. The CwdChanged hook fixes this by running a command every time Claude changes its working directory.

Add this to your .claude/settings.json:

{
  "hooks": {
    "CwdChanged": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "eval \"$(direnv export bash)\" && if [ -n \"$CLAUDE_ENV_FILE\" ]; then direnv export bash | grep 'export' >> \"$CLAUDE_ENV_FILE\"; fi"
          }
        ]
      }
    ]
  }
}

The CLAUDE_ENV_FILE variable is a special file Claude Code provides in hooks. Anything you write to it as export VAR=value lines gets loaded into Claude's environment for the rest of the session.

You can also watch .envrc files directly with the FileChanged hook so Claude reloads the environment whenever that file changes — without you needing to switch directories:

{
  "hooks": {
    "FileChanged": [
      {
        "matcher": ".envrc",
        "hooks": [
          {
            "type": "command",
            "command": "eval \"$(direnv export bash)\" && if [ -n \"$CLAUDE_ENV_FILE\" ]; then direnv export bash | grep 'export' >> \"$CLAUDE_ENV_FILE\"; fi"
          }
        ]
      }
    ]
  }
}

Keep Claude's environment in sync with your project without ever thinking about it.

via Claude Code Docs — Hooks