Agent Skills: Hook Routing Worker

Hook Routing Worker

NOTE: Startup and cleanup are handled by worker-base. This skill defines the WORK PROCEDURE.

When to Use This Skill

Features that add hook input/output capabilities (updatedInput, suppressOutput), enhance denial-based routing feedback, or integrate hooks with the routing system.

Work Procedure

1. Read the feature description carefully. Understand the hook protocol fields being added and how they integrate with the routing system.

2. Read source files. Before modifying:

   • Read the target hook(s) fully
   • Read .claude/lib/routing/denial-feedback-reader.cjs for denial feedback patterns
   • Read AGENTS.md for CC dangerous patterns reference

3. Write tests first (red). Create test file at tests/hooks/<descriptive-name>.test.cjs. Tests must cover:

   • New output fields (updatedInput, suppressOutput) present/absent in correct conditions
   • Integration with denial log (read/write/accumulate)
   • Edge cases (empty logs, malformed data, missing files)
   • Fail-open for advisory hooks, fail-closed for security hooks Run tests — they should FAIL (red).

4. Implement changes.

   • updatedInput: Return in hookSpecificOutput when the hook modifies the command (e.g., prepending safety prefixes). Must not appear when no modification needed.
   • suppressOutput: Return true when verbose block messages should not inflate context. Only on block events, never on allow.
   • Denial feedback: Use getDenialFeedback() from denial-feedback-reader.cjs. Handle missing/corrupted log gracefully.
   • Routing integration: Follow existing patterns in .claude/lib/routing/.

5. Run tests (green). All tests pass.

6. Run lint.

   pnpm lint
   npx prettier --check <modified-files>
   

Example Handoff

{
  "salientSummary": "bash-command-validator now returns updatedInput.command with safety prefix for multi-line scripts. suppressOutput:true on blocks. 22 tests.",
  "whatWasImplemented": "updatedInput logic: detect multi-line commands missing set -e, prepend set -euo pipefail. suppressOutput:true on exit-2 blocks only. Denial feedback integration tested with seeded logs.",
  "whatWasLeftUndone": "",
  "verification": {
    "commandsRun": [
      { "command": "node --test tests/hooks/bash-updated-input.test.cjs", "exitCode": 0, "observation": "22 tests passing" },
      { "command": "pnpm lint", "exitCode": 0, "observation": "0 errors" }
    ]
  }
}

When to Return to Orchestrator

• Hook output protocol doesn't support updatedInput or suppressOutput fields
• denial-feedback-reader.cjs has a different API than documented
• Routing integration requires changes to modules outside feature scope