jscpd

jscpd is a copy/paste detector for source code that finds duplicated, dead and overly complex code across languages.

Jscpd is a copy/paste detector for source code that finds duplicated, dead and overly complex code across hundreds of languages. It scores overall codebase health and fails builds when duplication crosses a set threshold. Built as a native Rust binary with a language server, it provides an MCP server and agent skills so AI agents can check for clones before writing more code. It detects identical tokens, renamed variables, similar syntax trees, and semantic duplicates using code embedding models. It integrates into pre-commit hooks, CI gates, and editors to make technical debt visible.

jscpd at a glance

Best for: Software engineer
Runs on: CLI, VS Code, JetBrains, self-hosted, open source
Pricing: Free
Released: May 2013
Category: AI coding tool
Website: jscpd.dev

Key features

Finds duplicated code in 224 programming languages
Runs as a native Rust binary without Node.js
Includes an MCP server for AI agents
Detects unused files, exports and imports
Provides a language server for editor diagnostics
Measures port progress between languages
Generates HTML, JSON, XML and README badges
Supports SARIF reports for code scanning

Use it for

Block commits when duplication exceeds a threshold
Fail pull requests in CI when clones appear
Let AI agents check for code clones via MCP
Rank and refactor the most complex files
Port codebases to another language securely

Alternatives to jscpd

jevgrep — Reduces coding agent costs by providing targeted, relevant repository context.
Sgrep — Runs locally without accounts or hosted indexes using small CPU models.
Codebase Memory MCP — High-speed indexing and persistent knowledge graphs for AI coding agents.
CodeGraph — It eliminates file crawling, reducing AI agent tool calls by 88% and cutting costs.
JS Reverse MCP — It organizes scripts, breakpoints, and network data for continuous AI agent reasoning.
code2prompt — Written in Rust for high speed and efficiency when handling large codebases.
jCodeMunch MCP — Cuts AI code-reading token costs by over 95 percent via tree-sitter symbol indexing.
Zed — Very fast native editor with parallel agents and multiplayer
BeautifulRust — It improves agent output using guidelines from five major Rust sources.
Ccm — Measures codebases, traces change impact, and estimates resource costs locally.
jcode — Optimized for massive parallelism with low memory usage per session.
daidocs — It keeps code graphs as plain text for lower token costs and better accuracy.

All jscpd alternatives