What is csswitch?

CSSwitch is a macOS desktop app, built with Rust and Tauri, that lets you connect Claude Science to AI models from other providers instead of only Anthropic's own models. It gives you a way to switch freely between mainstream Chinese and international model providers, an experimental Codex integration, and custom compatible API endpoints, all from one interface. The app supports a number of built in providers, including DeepSeek, Qwen, Zhipu GLM, Xiaomi MiMo, SiliconFlow, Kimi, MiniMax, and OpenRouter, as well as any custom endpoint that speaks the Anthropic Messages format or the OpenAI Chat Completions or Responses formats. To use a third party model, you open the model connection screen, pick a built in provider or fill in your own base URL for a compatible service, enter your API key and model name, save the configuration, and set it as active. When you then launch Science through CSSwitch, the model picker inside Science shows the real model name you configured rather than a generic placeholder. Switching back to your official Claude account and models stops the third party connection first. CSSwitch also has an experimental, off by default integration with Codex, where you log in through CSSwitch's own isolated browser session rather than touching your existing Codex login files, after which Codex models appear in the model connection list without automatically replacing your current provider. A separate part of the app manages Skills for Science: it shows which Skills currently exist in your Science organization along with their binding status, lets you import a local Skill package from a zip file, or has an AI agent install a Skill directly from a public GitHub URL through a narrow, purpose built installer that checks archive size, file count, and other safety details before committing anything. General purpose MCP server management is not yet available and is still being developed. For safety, third party mode runs with its own separate home directory, data directory, and local network gateway, so it does not read or modify your real Claude login or Science data, and API keys are stored locally with restricted file permissions. The public desktop build currently only supports Apple Silicon Macs, and CSSwitch is released under the MIT license.