ExplainThisRepo

The fastest way to understand any codebase in plain English using real project signals. Not blind AI summarization.

ExplainThisRepo analyzes real project signals; configs, entrypoints, manifests, dependencies graph, file structure and high-signal files producing a clear, structured EXPLAIN.md that explains what the codebase does and how it is organized in plain English.

Key Features

• Understand any GitHub repository in seconds
• Derives architectural summaries from repository structure and code signals. Not blind AI summarization.
• Translates complex code structures into plain English
• Extract architecture signals from configs, entrypoints, and manifests
• Works with GitHub repositories, local directories, private repositories, and monorepos
• Outputs the explanation to an EXPLAIN.md file in your current directory or prints it directly in the terminal
• Multiple explanation modes (quick, simple, detailed)

Installation

Option 1: install with pip (recommended):

Requirements: Python 3.9+

pip install explainthisrepo
explainthisrepo owner/repo

# pip install explainthisrepo
# explainthisrepo .

Alternatively,

pipx install explainthisrepo
explainthisrepo owner/repo

To install support for specific models:

pip install explainthisrepo[gemini]
pip install explainthisrepo[openai]
pip install explainthisrepo[anthropic]
pip install explainthisrepo[groq]

Option 2: Install with npm

Install globally and use forever:

npm install -g explainthisrepo
explainthisrepo owner/repo

# npm install -g explainthisrepo
# explainthisrepo .

Or without install:

npx explainthisrepo owner/repo

Replace owner/repo with the GitHub repository identifier (e.g., facebook/react).

Option 3: Download standalone binary

Prebuilt standalone binaries are available for macOS, Linux, and Windows.

Standalone binaries require no Python or Node installation and run as a single executable.

Download the latest release:

github.com/calchiwo/ExplainThisRepo/releases/latest

Or install directly:

macOS

curl -L https://github.com/calchiwo/ExplainThisRepo/releases/latest/download/explainthisrepo-darwin-arm64 -o explainthisrepo
chmod +x explainthisrepo

Linux

curl -L https://github.com/calchiwo/ExplainThisRepo/releases/latest/download/explainthisrepo-linux-x64 -o explainthisrepo
chmod +x explainthisrepo

Windows (PowerShell)

curl -L https://github.com/calchiwo/ExplainThisRepo/releases/latest/download/explainthisrepo-win-x64.exe -o explainthisrepo.exe

Configuration

ExplainThisRepo supports multiple LLM models:

• Gemini
• OpenAI
• Ollama (local or cloud-routed)
• Anthropic
• Groq
• OpenRouter

Use the built-in init command to configure your preferred model:

explainthisrepo init
# or npx explainthisrepo init

For details about how initialization works, see INIT.md.

Flag options

• (no flag) → Full repository explanation written to EXPLAIN.md

• --quick → One-sentence summary

• --simple → Short, simplified explanation

• --detailed → Deeper explanation including structure and architecture

• --stack → Tech stack breakdown from repo signals

• --version → Check installed CLI version

• --help → Show usage guide

• --doctor → Check system health and active model diagnostics

• --llm → Override provider selection

• --token/-t → Set GitHub token for private repositories and to avoid rate limits

Flexible Repository and Local Directory Input

Accepts various formats for repository input, full GitHub URLs (with or without https), owner/repo format, issue links, query strings, and SSH clone links

explainthisrepo https://github.com/owner/repo
explainthisrepo github.com/owner/repo
explainthisrepo https://github.com/owner/repo/issues/123
explainthisrepo https://github.com/owner/repo?tab=readme
explainthisrepo [email protected]:owner/repo.git
explainthisrepo .
explainthisrepo ./path/to/directory

All inputs are normalized internally to owner/repo.

Model selection

The --llm flag selects which configured model backend to use for the current command.

explainthisrepo owner/repo --llm gemini
explainthisrepo owner/repo --llm openai
explainthisrepo owner/repo --llm ollama
explainthisrepo owner/repo --llm anthropic
explainthisrepo owner/repo --llm openrouter
explainthisrepo owner/repo --llm groq

--llm works with all modes (--quick, --simple, --detailed).

Command line usage

Default

Writes a full explanation to EXPLAIN.md:

explainthisrepo owner/repo
#e.g. explainthisrepo vercel/next.js

Quick mode

Prints a one-sentence summary to stdout:

explainthisrepo owner/repo --quick
# explainthisrepo facebook/react --quick

$ explainthisrepo vercel/next.js --quick

Next.js is a React framework that provides server-side rendering,
file-based routing, API routes, and build tooling for fullstack
web applications.

Detailed mode

Writes a more detailed explanation of repository structure and architecture:

explainthisrepo owner/repo --detailed

Simple mode

Prints a short, simplified explanation to stdout. No files are written.

explainthisrepo owner/repo --simple

Stack detector

Tech stack breakdown detected from repo signals. No LLM calls are made.

explainthisrepo owner/repo --stack

Local Directory Analysis

ExplainThisRepo can analyze local directories directly in the terminal, using the same modes and output formats as GitHub repositories

explainthisrepo .
explainthisrepo ./path/to/directory

This works with all existing modes:

explainthisrepo . --quick
explainthisrepo . --simple
explainthisrepo . --detailed
explainthisrepo . --stack

When analyzing a local directory:

• Repository structure is derived from the filesystem
• High signal files (configs, entrypoints, manifests) are extracted locally
• No GitHub APIs calls are made
• All prompts and outputs remain identical

This allows analysis of projects directly from the local filesystem, without requiring a GitHub repository.

For private repositories, use the --token/-t option.

Setting a GITHUB_TOKEN environment variable is recommended to avoid rate limits when analyzing public repositories.

export GITHUB_TOKEN=yourActualTokenHere

Version

Check the installed CLI version:

explainthisrepo --version

Diagnostics

Use the --doctor flag to verify the environment, network connectivity, and API key configuration:

explainthisrepo --doctor

Termux (Android) install notes

Termux has some environment limitations that can make pip install explainthisrepo fail to create the explainthisrepo command in $PREFIX/bin.

However, it's recommended you install using:

pip install --user -U explainthisrepo

Make sure your user bin directory is on your PATH:

export PATH="$HOME/.local/bin:$PATH"

Tip: Add the PATH export to your ~/.bashrc or ~/.zshrc so it persists.

Alternative (No PATH changes)

If you do not want to modify PATH, you can run ExplainThisRepo as a module:

python -m explain_this_repo owner/repo

Gemini support on Termux

Installing Gemini support may require building Rust-based dependencies on Android, which can take time on first install:

pip install --user -U "explainthisrepo[gemini]"

For mobile environments like Termux where compiling Python dependencies can be slow, you can also run ExplainThisRepo using the Node.js version:

npx explainthisrepo owner/repo

Special Thanks

• @Spectra010s for implementing the Node.js version of ExplainThisRepo and improving installation support for mobile environments like Termux
• @HalxDocs for implementing the --detailed mode for deeper architectural explanations

Contributions

Contributions are welcome!

If you find a bug, have an idea, or want to improve the tool:

• See CONTRIBUTING for setup and guidelines
• Open an issue for bugs/feature requests
• Or submit a pull request for fixes/improvements

License

This project is licensed under the MIT License. See the LICENSE file for details.

Author

Caleb Wodi

• Email: [email protected]
• LinkedIn: @calchiwo
• Twitter: @calchiwo