Repomix - Codebase Packing for AI

Pack your entire repository into a single, AI-friendly file optimized for LLMs like Claude, ChatGPT, Gemini, and more.

When to Use This Skill

• Feeding codebase to AI for analysis or refactoring

• Generating comprehensive code reviews

• Creating documentation from code

• Preparing context for AI-assisted development

• Analyzing remote repositories without cloning

• Token counting for LLM context limits

Quick Start

Pack current directory (no install required)

npx repomix@latest

Pack specific directory

npx repomix path/to/directory

Pack with compression (~70% token reduction)

npx repomix --compress

Copy output to clipboard

npx repomix --copy

Default output: ./repomix-output.xml in current directory

Examples

Example: Prepare codebase for Claude review

User: "Pack my src folder for Claude to review the architecture" → npx repomix --include "src/**/*" --style xml --copy → Output copied to clipboard, ready to paste into Claude

Example: Analyze remote repo without cloning

User: "I want to understand how shadcn/ui implements its button" → npx repomix --remote shadcn-ui/ui --include "/button//*" --compress → Generates focused output of button component

Example: Prepare PR diff for review

User: "Pack only the files I changed for a code review" → git diff --name-only main | npx repomix --stdin --compress → Packs only modified files with compression

Example: Check token usage before sending to AI

User: "Is my codebase too large for GPT-4?" → npx repomix --token-count-tree → Shows token breakdown per file/directory

Example: Generate skills reference from library

User: "Create a Claude skill from the zod repository" → npx repomix --remote colinhacks/zod --skill-generate zod-reference → Generates AI-optimized reference documentation

Output Formats

XML (default) - best for Claude

npx repomix --style xml

Markdown - human readable

npx repomix --style markdown

JSON - programmatic processing

npx repomix --style json

Plain text

npx repomix --style plain

Token Optimization

LLM Context Limits Reference

Model Context Window Typical Repo Fit

Claude 3.5/Opus 200K tokens Large monorepos

GPT-4 Turbo/4o 128K tokens Medium projects

Gemini 1.5 Pro 1M tokens Very large codebases

Gemini 1.5 Flash 1M tokens Very large codebases

Token Analysis

Show token count tree

npx repomix --token-count-tree

Filter by minimum tokens (show files with 1000+ tokens)

npx repomix --token-count-tree 1000

Split output for large codebases

npx repomix --split-output 1mb

File Selection

Include Patterns

Include only TypeScript files

npx repomix --include "**/*.ts"

Include multiple patterns

npx repomix --include "src//*.ts,/*.md"

Include specific directories

npx repomix --include "src//*,tests//*"

Ignore Patterns

Ignore test files

npx repomix --ignore "**/*.test.ts"

Ignore multiple patterns

npx repomix --ignore "**/*.log,tmp/,dist/"

Combine include and ignore

npx repomix --include "src//*.ts" --ignore "/*.test.ts"

Stdin Input

From find command

find src -name "*.ts" -type f | npx repomix --stdin

From git tracked files

git ls-files "*.ts" | npx repomix --stdin

Interactive selection with fzf

find . -name "*.ts" -type f | fzf -m | npx repomix --stdin

From ripgrep

rg --files --type ts | npx repomix --stdin

Common Workflows

PR Review Preparation

Pack only changed files for review

git diff --name-only main | npx repomix --stdin --compress

Pack with diff context included

npx repomix --include-diffs --compress

Architecture Analysis

Pack structure without implementation details

npx repomix --compress --include "src//*" --ignore "/.test."

Focus on specific layer

npx repomix --include "src/api//*,src/services//*" --compress

Documentation Generation

Pack with full context for docs

npx repomix --include "src//*,/*.md" --style markdown

Include git history for changelog

npx repomix --include-logs --include-logs-count 50

Dependency Analysis

Pack only config and dependency files

npx repomix --include "package.json,tsconfig.json,**/.config."

Remote Repositories

Pack remote repository

npx repomix --remote https://github.com/user/repo

GitHub shorthand

npx repomix --remote user/repo

Specific branch

npx repomix --remote user/repo --remote-branch main

Specific commit

npx repomix --remote user/repo --remote-branch 935b695

Branch URL format

npx repomix --remote https://github.com/user/repo/tree/feature-branch

Code Compression

Tree-sitter powered compression extracts signatures while removing implementation details.

Supported Languages

Tree-sitter compression works with: JavaScript, TypeScript, Python, Ruby, Go, Rust, Java, C, C++, C#, PHP, Swift, Kotlin, and more.

Usage

npx repomix --compress

Combine with remote

npx repomix --remote user/repo --compress

Before compression:

const calculateTotal = (items: Item[]) => { let total = 0; for (const item of items) { total += item.price * item.quantity; } return total; };

After compression:

const calculateTotal = (items: Item[]) => { /* ... */ };

Git Integration

Include git logs (last 50 commits)

npx repomix --include-logs

Specify commit count

npx repomix --include-logs --include-logs-count 20

Include git diffs

npx repomix --include-diffs

Combine logs and diffs

npx repomix --include-logs --include-diffs

Configuration

Initialize Config

Create repomix.config.json

npx repomix --init

Global config

npx repomix --init --global

Configuration File

{ "$schema": "https://repomix.com/schemas/latest/schema.json", "output": { "filePath": "repomix-output.xml", "style": "xml", "compress": false, "removeComments": false, "showLineNumbers": false, "copyToClipboard": false }, "include": ["src//*", "/.md"], "ignore": { "useGitignore": true, "useDefaultPatterns": true, "customPatterns": ["**/.test.ts", "dist/"] }, "security": { "enableSecurityCheck": true } }

Docker Usage

Pack current directory

docker run -v .:/app -it --rm ghcr.io/yamadashy/repomix

Pack specific directory

docker run -v .:/app -it --rm ghcr.io/yamadashy/repomix path/to/directory

Remote repository

docker run -v ./output:/app -it --rm ghcr.io/yamadashy/repomix --remote user/repo

MCP Server Integration

Run as Model Context Protocol server for AI assistants:

npx repomix --mcp

Configure for Claude Code

claude mcp add repomix -- npx -y repomix --mcp

Available MCP Tools

When running as MCP server, provides:

Tool Description

pack_codebase

Pack local directory into AI-friendly format

pack_remote_repository

Pack GitHub repository without cloning

read_repomix_output

Read contents of generated output file

file_system_tree

Get directory tree structure

Claude Agent Skills Generation

Generate skills format output for Claude:

Generate skills from local directory

npx repomix --skill-generate

Generate with custom name

npx repomix --skill-generate my-project-reference

From remote repository

npx repomix --remote user/repo --skill-generate

CLI Options Reference

Option Description

-o, --output <file>

Output file path

--style <style>

Output format: xml, markdown, json, plain

--compress

Enable Tree-sitter compression

--include <patterns>

Include files matching glob patterns

-i, --ignore <patterns>

Exclude files matching patterns

--remote <url>

Process remote repository

--remote-branch <name>

Branch, tag, or commit for remote

--stdin

Read file paths from stdin

--copy

Copy output to clipboard

--token-count-tree

Show token counts per file

--split-output <size>

Split output by size (e.g., 1mb)

--include-logs

Include git commit history

--include-diffs

Include git diffs

--no-security-check

Skip sensitive data detection

--mcp

Run as MCP server

--skill-generate

Generate Claude skills format

--init

Create configuration file

--help

Show all available options

Troubleshooting

Issue Solution

Output too large for LLM Use --compress or filter with --include

Missing expected files Check .repomixignore , .gitignore , and ignore patterns

Secrets detected (blocking) Review flagged files; use --no-security-check if false positive

Memory issues on large repos Use --split-output 1mb to chunk output

Remote repo access denied Check URL format; ensure repo is public or use SSH

Compression not working Verify language is supported by Tree-sitter

Output not in clipboard Ensure clipboard access; try --output - | pbcopy on macOS

Ignore Files

Repomix respects multiple ignore sources (priority order):

• ignore.customPatterns in config

• .repomixignore (Repomix-specific)

• .ignore (ripgrep compatible)

• .gitignore

• Default patterns (node_modules, .git, etc.)

Security

Repomix includes Secretlint for detecting sensitive information:

Security check enabled by default

npx repomix

Disable security check (use with caution)

npx repomix --no-security-check

Detected secret types: API keys, tokens, passwords, private keys, AWS credentials, database connection strings, and more.

Best Practices

• Use compression for large codebases to reduce token count (~70% reduction)

• Filter with --include to focus on relevant files

• Use --token-count-tree to identify large files before packing

• Split output when hitting AI context limits

• Include git logs for evolution context when needed

• Use XML style for Claude (optimized for XML tags)

• Use Markdown for human-readable output or other LLMs

• Check token counts against your target LLM's context window

• Review security warnings before sharing packed output

Requirements

• Node.js 18.0.0 or higher

• npm or npx available in PATH

Resources

• Website: https://repomix.com

• GitHub: https://github.com/yamadashy/repomix

• Chrome Extension: Repomix - Chrome Web Store

• VSCode Extension: Repomix Runner