jscpd

name	jscpd
description	Fast native Rust clone of jscpd. Detect duplicated code and measure duplication percentages.

jscpd-rs

Fast native Rust clone of jscpd. Use this skill to run jscpd-rs and understand its output.

Quick Start

# Run with ai reporter (compact output optimized for agents)
npx jscpd-rs --reporters ai <path>

# With ignore patterns
npx jscpd-rs --reporters ai --ignore "**/node_modules/**,**/dist/**" <path>

# Scope to specific formats
npx jscpd-rs --reporters ai --format "javascript,typescript" <path>

AI Reporter Output Format

The ai reporter produces compact, token-efficient output designed for agent consumption:

Clones:
src/ foo.ts:10-25 ~ bar.ts:42-57
src/utils/helpers.ts:100-120 ~ src/utils/other.ts:5-25
---
3 clones · 4.2% duplication

Each line represents one clone pair:

• Same file: path/file.ts 10-25 ~ 45-60
• Same directory: shared/prefix/ file-a.ts:10-25 ~ file-b.ts:42-57
• Different paths: path/a.ts:10-25 ~ path/b.ts:42-57

Options

Option	Description
--reporters ai	Use the AI-optimized reporter
--reporters html	Generate HTML report
--reporters json	Output JSON report
--min-tokens N	Minimum tokens to consider a duplication
--min-lines N	Minimum lines to consider a duplication
--threshold N	Exit with error if duplication percentage exceeds N
--ignore "glob"	Ignore patterns, comma-separated
--format "list"	Limit to specific languages
--pattern "glob"	Glob pattern to select files
--gitignore	Respect .gitignore
--output "path"	Directory to write reports to
--silent	Suppress output
--no-tips	Disable terminal tips
--config "path"	Path to .jscpd.json config file

Configuration File

Create a .jscpd.json in your project root:

{
  "threshold": 0,
  "reporters": ["ai"],
  "ignore": ["**/node_modules/**", "**/dist/**", "**/*.min.*"],
  "format": ["typescript", "javascript"],
  "minLines": 5,
  "minTokens": 50,
  "output": "./reports/jscpd"
}

Refactoring Duplicated Code

Once duplicates are detected, use the dry-refactoring skill for a guided workflow to eliminate them:

npx skills add vv-bogdanov/jscpd-rs --skill dry-refactoring