Hook format validation changed in Claude Code v2.1.71 — verify agentlog compatibility

[albireo3754]

Background

Claude Code v2.1.71 tightened validation on ~/.claude/settings.json hook entries.
The matcher field now must be a string (glob/regex pattern or empty string "").

The new documented format is:

{
  "UserPromptSubmit": [
    {
      "matcher": "",
      "hooks": [{ "type": "command", "command": "agentlog hook" }]
    }
  ]
}

Hooks with matcher set to an object (old format used by some tools) now produce validation errors like:

Invalid Settings
~/.claude/settings.json
 └ hooks
   ├ PostToolUse
   │ └ 0
   │   └ matcher: Expected string, but received object
   └ PreToolUse
     ├ 0
     │ └ matcher: Expected string, but received object

Hooks use a new format with matchers. Example:
{"PostToolUse": [{"matcher": {"tools": ["BashTool"]}, ...}]}
Learn more: https://code.claude.com/docs/en/hooks

Agentlog Status

agentlog's HOOK_ENTRY (src/claude-settings.ts) currently registers:

export const HOOK_ENTRY = {
  matcher: "",          // ✅ empty string — likely valid
  hooks: [
    { type: "command", command: "agentlog hook" },
  ],
};

matcher: "" is an empty string, which should satisfy the new validation. However, this needs verification against the latest Claude Code release.

Tasks

• Confirm matcher: "" is accepted by Claude Code 2.1.71+ (run claude doctor after agentlog init)
• If invalid, update HOOK_ENTRY to match the new required format
• Add a agentlog doctor check that validates the registered hook passes Claude Code's built-in settings validation
• Detect and migrate any stale hook entries registered in old formats (future-proofing)

Reference

• Claude Hooks docs: https://code.claude.com/docs/en/hooks
• Claude Code changelog: v2.1.71 (claude --version or claude doctor to confirm)

/cc Affects agentlog init, agentlog uninstall, and the doctor subcommand.