name: detecting-existing-threads description: Detects existing PR review threads to prevent duplicate comments. Use BEFORE posting any inline comments. Fetches resolved and open threads, then matches against planned findings.

Detecting Existing Threads

Purpose

Prevent duplicate comments by detecting existing review threads before posting new findings.

Required Tools

• Bash(gh pr view:*) - Get general PR comments
• Bash(gh api graphql*reviewThreads*-f owner=*-f repo=*-F pr=*:*) - Get resolved threads
• Bash(./scripts/get-review-threads.sh:*) - Script wrapper

Step 1: Determine PR Number

Use this priority order:

1. GitHub Actions environment:

   • Check GITHUB_EVENT_PATH environment variable
   • Extract PR number from event payload: .pull_request.number
   • Get repo from GITHUB_REPOSITORY ("owner/repo" format)

2. Conversation context:

   • Direct number: "123" → use 123
   • PR URL: extract from https://github.com/org/repo/pull/456
   • Text reference: "PR #789" → extract 789

3. Local review mode:

   • No PR number available → skip thread detection entirely

Step 2: Fetch Thread Data

Capture BOTH comment sources:

# General PR comments
gh pr view <PR_NUMBER> --json comments

# Inline resolved review threads (REQUIRED - gh pr view misses these)
./scripts/get-review-threads.sh <PR_NUMBER> <OWNER> <REPO>

Step 3: Parse Into Structure

Build this JSON structure from merged results:

{
  "total_threads": 5,
  "threads": [
    {
      "location": "src/auth.ts:45",
      "severity": "CRITICAL",
      "issue_summary": "SQL injection risk in query builder",
      "resolved": false,
      "author": "claude",
      "path": "src/auth.ts",
      "line": 45
    }
  ]
}

Severity detection from emoji prefix:

• ❌ → CRITICAL
• ⚠️ → IMPORTANT
• ♻️ → DEBT
• 🎨 → SUGGESTED
• ❓ → QUESTION

Thread Matching Logic

Before creating any new comment, check for matches:

Handling Matches

• Issue persists unchanged → Respond in existing thread
• Issue resolved → Note resolution, don't re-raise
• Issue evolved → Create new comment explaining change