duplicate-detector

name	duplicate-detector
description	Compares a target GitHub issue against a list of existing open issues to detect duplicates based on semantic similarity. Use when checking for duplicate issues or performing issue deduplication.

Duplicate Detector

This skill provides instructions for comparing a target GitHub issue against a list of existing open issues to determine if the target issue is a duplicate.

Input

The input consists of:

1. Target Issue: Title and body text of the issue being evaluated.
2. Existing Issues: A list of open issues, where each entry includes the issue number (e.g., #128), title, and body text.

Detection Rules

1. Semantic Matching: Compare issues based on the semantic similarity of the underlying core problem described, rather than relying on exact wording.
2. Confidence Assignment:
   • high: Same root cause and same feature area.
   • medium: Similar symptoms, but different area or unclear root cause.
   • low: Superficially similar but likely different bugs.
3. Fallback / No Match:
   • If no likely duplicate is found, set is_duplicate to false, duplicate_of to null, and confidence to "low".

Output Requirement

• The output MUST be strict JSON only.
• Do NOT wrap the output in markdown codeblocks (e.g., do not use ```json or ```).
• Do NOT include any preamble, introduction, explanation, or trailing text outside of the JSON object.

JSON Schema Structure

{
  "is_duplicate": boolean,
  "duplicate_of": "#128" | null,
  "confidence": "high" | "medium" | "low"
}