FoxTrans

FoxTrans is a lightweight real-time AI voice translator for VRChat. It captures microphone audio, filters it with WebRTC VAD, sends it to an OpenRouter-compatible API, and sends the translated text to VRChat over OSC.

Requirements

• Windows x64
• .NET SDK 10.0.302 or a later .NET 10 feature-band SDK (selected through global.json)
• Visual Studio is not required. VS Code with C# Dev Kit works directly with FoxTrans.slnx.

Build and publish

Clone the repository and run the single canonical publish command from the repository root:

git clone https://github.com/MrShitFox/FoxTrans.git
cd FoxTrans
dotnet publish -c Release

The result is FoxTrans\bin\Release\net10.0\win-x64\publish\FoxTrans.exe.

It is a self-contained Windows x64 single-file executable: the .NET runtime and managed/native dependencies are bundled, so a target computer does not need a separately installed .NET Runtime.

In VS Code, the shared Build and Publish Release tasks run dotnet build and the same canonical publish command respectively.

First run and configuration

Run FoxTrans.exe once. It creates a default config.json in its current working directory and exits. Add your OpenRouter API key to that file, enable OSC in VRChat (Options -> OSC -> Enable), then run the executable again.

config.json is local configuration and is intentionally ignored by Git because it can contain an API key. Do not commit it.

{
  "Api": {
    "Key": "sk-or-v1-YOUR_API_KEY",
    "Endpoint": "https://openrouter.ai/api/v1/chat/completions",
    "Model": "google/gemini-2.5-flash",
    "Prompt": "Translate this audio to English. Reply ONLY with the final translated text, no quotes or explanations."
  },
  "Vad": {
    "MinSpeechFrames": 12,
    "MinSilenceFrames": 50,
    "PreRollFrames": 30,
    "MinPhraseLengthMs": 1200
  },
  "Osc": {
    "IpAddress": "127.0.0.1",
    "Port": 9000,
    "EnableTypingIndicator": true
  }
}