Claude Code Proxy

A development tool for intercepting and visualizing Claude Code API requests. By hijacking Claude Code's network requests, it captures and displays all prompts and tool calls in real-time, helping developers understand and debug Claude Code's working mechanism.

Features

• 🔍 API Request Interception: Automatically hijack Claude Code API calls
• 📊 Visual Interface: Intuitive web interface displaying all requests and responses
• 🛠️ Tool Call Analysis: Detailed recording and visualization of tool invocations
• 💬 Prompt Visualization: Clear display of system prompts and user messages
• 📝 Session Management: Support for recording and switching between multiple sessions
• 🎨 Beautiful UI: Modern dark theme interface

Installation

npm install -g claude-code-proxy

Usage

Starting the Proxy

claude-code-proxy

After running, it will automatically:

1. Modify the globally installed Claude Code CLI file
2. Start a local server (http://localhost:3000)
3. Automatically open the browser to view the interface

How It Works

The tool works through the following steps:

1. CLI Hijacking: Modify Claude Code's cli.js file, injecting interception code
2. Request Interception: Intercept beta.messages.create API calls
3. Data Recording: Record all requests and responses to log files
4. Visual Display: Parse and display data through a web interface

Interface Features

Main Interface

• Conversation: Display current session's input and output
• Global Tool Set: Show all available tool definitions
• Guessed System Prompts: Intelligently identified system prompts

Function Buttons

• Create New Log: Create a new log session
• Choose Example: Select historical session records
• Navigation Buttons: Switch between multiple sessions

Data Display

• Input Panel:

  • Model parameters (model, max_tokens, temperature)
  • System messages
  • Available tool list
  • User messages

• Output Panel:

  • Response type and token usage
  • AI response content (supports Markdown rendering)
  • Tool call activity
  • Other response fields

Project Structure

claude-code-proxy/
├── bin/
│   └── main.js
├── script/
│   ├── main.js
│   └── alternateFile.js
├── public/
│   ├── index.html
│   └── parser.js
├── messages/
│   └── messages.log
└── package.json

Technical Implementation

CLI Modification

The tool automatically finds the globally installed @anthropic-ai/claude-code package and modifies its cli.js file:

1. Backup the original file as cli.bak
2. Format code using js-beautify
3. Inject interception code into the constructor
4. Reset executable permissions

Data Interception

The injected code will:

• Intercept this.beta.messages.create() calls
• Record input parameters to log files
• Intercept streaming and non-streaming responses
• Record tool call details

Log Format

Log files use the following format:

---Session 2024-01-01T00:00:00.000Z---
2024-01-01T00:00:00.000Z uid=abc123 input: {"messages":[...],"tools":[...]}
2024-01-01T00:00:01.000Z uid=abc123 stream.final: {"text":"...","tools":[...]}

Security Notice

This tool is for development and debugging purposes only and modifies Claude Code installation files. Before using, please ensure:

• Understanding of how the tool works
• Use in development environments
• Regular backup of important data

System Requirements

• Node.js >= 18
• Claude Code CLI installed (@anthropic-ai/claude-code)
• Supported OS: macOS, Linux, Windows

Troubleshooting

Claude Code Not Found

Make sure Claude Code CLI is properly installed:

npm install -g @anthropic-ai/claude-code

Permission Issues

On macOS/Linux, you may need administrator privileges:

sudo claude-code-proxy

Reset Claude Code

To restore original Claude Code:

1. Find the cli.bak file in the installation directory
2. Rename it to cli.js

Development

Local Development

git clone https://github.com/your-username/claude-code-proxy.git
cd claude-code-proxy
npm install
npm link

Contributing

1. Fork this repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

License

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

Author

Venus Shan

Important Notes

⚠️ Important Reminder:

• This tool modifies Claude Code installation files
• Only recommended for use in development environments
• Please backup important data before use
• Data recorded by the tool may contain sensitive information, please handle with care

Changelog

v0.0.3

• Added session management functionality
• Improved web interface design
• Optimized log parser performance

v0.0.2

• Fixed tool call recording issues
• Added Markdown rendering support

v0.0.1

• Initial release
• Basic API interception functionality