ChatMock provides a local server that exposes an OpenAI-compatible API, allowing users to programmatically access OpenAI models through their existing ChatGPT Plus/Pro subscription without needing an API key. This is beneficial for developers and power users who want to integrate advanced AI models into their applications or use alternative chat UIs with their paid ChatGPT account.

How It Works

ChatMock leverages the OAuth client of OpenAI's Codex CLI tool to authenticate with your ChatGPT account. It then acts as a proxy, forwarding requests to OpenAI's services and returning responses. This approach bypasses the need for traditional API keys, instead relying on your logged-in session, and enables access to models like GPT-5.

Quick Start & Requirements

• Installation: Download GUI application from releases (Mac/Windows) or run via Python:

  git clone https://github.com/RayBytes/ChatMock.git
  cd ChatMock
  python chatmock.py login
  python chatmock.py serve
  

• Prerequisites: Active, paid ChatGPT account. Python 3.x for Python server.
• Setup: Requires login via python chatmock.py login.
• Docs: README

Highlighted Details

• Supports OpenAI and Ollama compatible API endpoints.
• Enables programmatic access to models like GPT-5 and Codex-mini.
• Supports tool calling, vision/image understanding, and configurable thinking summaries.
• Offers larger context size than the standard ChatGPT app.

Maintenance & Community

• Project appears to be actively maintained with recent updates.
• No specific community links (Discord/Slack) are provided in the README.

Licensing & Compatibility

• The README does not explicitly state a license.
• The project is described as an "educational exercise" and is not affiliated with OpenAI. Use is at your own risk.

Limitations & Caveats

• Requires an active, paid ChatGPT subscription.
• May have lower rate limits compared to the official ChatGPT application.
• System prompt instructions in prompt.md are not modifiable.
• Windows GUI testing is limited due to lack of a Windows machine.